Technical resources
The technical desk for people who specify and apply
Paste-ready specification clauses, the standards table you keep open while writing a tender, and the site checks that decide whether work starts today. Written for Indian practice, and free to use.
Start where you sit
Ten roles, ten different problems
An architect writing a clause and an applicator standing on a damp slab need opposite things from the same supplier. Pick the one that describes your day.
Specification library
Clauses you can paste into a tender
Performance-based and brand-neutral, as a tender clause has to be. Square brackets mark the values your project decides. Each one carries the codes it cites, how the item is measured, and the mistake that most often makes it fail on site.
WaterproofingExposed Liquid-Applied Waterproofing to RCC Terrace and Roof Slabs
Accessible and inaccessible RCC terraces and roof slabs where the waterproofing membrane is the final exposed surface, including upstands, parapet junctions, fillets and rainwater outlets.
The Contractor shall provide and lay an exposed [name the system type: polyurethane / polyurea / acrylic-cementitious] liquid-applied waterproofing membrane to the RCC roof slab, to the dry film thickness, primer, number of coats, crack-bridging class and service life stated against that named system. Where more than one system type is retained, a separate thickness and test schedule shall be attached to each.
The deck shall be mechanically cleaned to remove laitance, curing compound and loose material. Blowholes and honeycombs shall be made good with the system’s repair mortar. Dormant cracks shall be routed to not less than [6] mm wide by [6] mm deep and filled with the system’s repair mortar or resin. Live or moving cracks, construction joints and pour joints shall be treated with a fabric-reinforced detail band not less than [200] mm wide over a bond-breaker tape, applied before the field coats. The Engineer shall determine whether a crack is live; the membrane shall achieve crack-bridging class [X] classified under EN 1504-2 by the EN 1062-7 method.
Screed to falls of not less than [1 in 100] towards outlets shall be laid, cured and dried before priming, with outlet spacing not exceeding [X] m and catchment area not exceeding [X] m2 per outlet. Surface regularity shall not exceed [5] mm under a 3 m straightedge. Outlets shall be set not less than [10] mm below the surrounding finished surface. Coved fillets of [75] mm radius shall be formed at all slab-to-upstand junctions. The membrane shall be turned up not less than [300] mm at parapets, terminated in a groove or drip, and dressed [150] mm into each outlet. Where the terrace is accessible, a UV-stable wear coat with anti-skid aggregate shall be applied over the membrane.
Dry film thickness shall be not less than [X] microns, verified by all three of: wet film readings taken during application and converted using the declared volume solids; recorded consumption per m2 against a marked-out grid; and dry film measurement on steel witness panels coated alongside each area and retained until handover. Disputes shall be resolved by destructive coupon and microscopic measurement.
The completed roof shall be flood-tested with outlets temporarily plugged and water not less than [25] mm deep over the highest point of the area under test, the area sub-divided into bays by temporary dams where the fall exceeds the test depth. Duration shall be not less than [24] hours. The soffit and all penetrations shall be inspected and signed off before draining, with start and finish levels recorded and evaporation allowed for. The imposed load of the flood test shall be confirmed as acceptable by the structural engineer before filling. A post-completion drainage check shall show no residual pool exceeding [3] mm depth after [30] minutes.
Most common failure. Priming a screed that is still green. The trade programme almost always forces the membrane on within days of screeding, and trapped moisture blisters the film weeks later. Make a substrate moisture check a written hold point — ‘dry to touch’ is not a moisture test, and the screed drying time, not the membrane, governs the programme.
WaterproofingProtected (Covered) Waterproofing beneath Screed, Insulation or Tile Finish
Roof and terrace slabs where the waterproofing is buried beneath a protection screed, thermal insulation, pressed tiles or pavers, and is therefore not accessible for later inspection or local repair.
The Contractor shall lay a [torch-applied polymer-modified bituminous membrane of [X] mm / liquid-applied membrane] over the prepared RCC slab. The drawings shall state whether falls are formed in the structural slab, in a sub-screed below the membrane, or in the protection screed above. Where falls are formed above the membrane, twin-level (two-stage) outlets shall be provided with a drainage and filter layer at membrane level and the clamping ring detailed. Where a sub-screed forms the falls, it shall be measured separately and its drying shall be a hold point before priming.
Surfaces shall be free of laitance, sharp projections and standing water and shall receive the specified primer at the stated rate. Sheets shall be laid with side laps not less than [100] mm and end laps not less than [150] mm, staggered and fully bonded with continuous bleed at every lap; laps shall be probe-tested. The membrane shall be turned up not less than [300] mm at all upstands over a [75] mm coved fillet and mechanically terminated.
The membrane shall declare, with test method and certificate: reinforcement type and mass (non-woven polyester, g/m2), nominal thickness, softening point, tensile strength and elongation in both directions, low-temperature flexibility and heat resistance, and the product standard it is certified to (EN 13707 for reinforced bituminous sheets, or equivalent evidenced by a current certificate from an accredited body).
Torch application shall be carried out under a daily hot-work permit, with a trained fire watch present during work and for not less than [60] minutes after, and extinguishers and water at the working face. LPG storage and manifolding shall follow the site fire plan. Direct torching on to or against combustible insulation, combustible parapet finishes and existing membrane at laps is prohibited unless a torch-safe detail is specified.
The membrane shall be flood-tested as for exposed roofs — outlets plugged, water not less than [25] mm over the highest point of the bay under test, not less than [24] hours, soffit and penetrations inspected and signed off before draining. Protection board or screed shall follow within [7] days, with falls, reinforcement and movement joints as detailed.
Most common failure. Letting the protection screed go down before the flood test and soffit inspection are signed off. Once the screed is on, a leak cannot be traced and the entire finish has to come off to find it. Note also that BIS has no product specification for APP or SBS polymer-modified membranes — IS 13826 gives test methods written around the older felts of IS 1322 — so the membrane’s own declared properties are what actually govern its quality, and they have to be in the clause.
WaterproofingTanking to Basement Rafts and Retaining Walls
Below-ground RCC rafts, retaining walls, kickers and construction joints of basements subject to soil moisture or hydrostatic head where a defined internal dryness grade is required.
The Contractor shall provide a tanking system achieving the [Grade 2 / Grade 3] internal environment to BS 8102, for a recorded groundwater level and design head of [X] m. The specification shall state the BS 8102 protection Type or combination required to achieve that Grade — Type A (barrier), Type B (structurally integral) or Type C (drained) — and shall not leave the Grade to be achieved by a membrane alone. The structural concrete is the first line of defence; mix, cover and crack-width limits shall comply with the structural specification.
The specification shall state the excavation and shoring assumption on which the clause is based. Where there is no external working space — contiguous, secant, diaphragm or soldier-pile walls with the RCC cast directly against the shoring, which is the normal condition on Delhi NCR and metro sites — a pre-applied fully bonded membrane shall be fixed against the blinding and the shoring face with concrete cast against it, or a Type B watertight concrete design shall be combined with internal Type C drained protection. The Contractor shall confirm the site condition before pricing.
The selected system shall be specified in its own sub-clause with the preparation, sequence, lap, termination, protection and backfill requirements that apply to it. A pre-applied fully bonded sheet, a post-applied self-adhesive sheet and a crystalline cementitious treatment are not interchangeable and shall not be offered under one set of workmanship requirements: the first two have opposite sequences, and the third is a Type B integral treatment that is neither lapped nor protected with board. Where an integral admixture is used, its type, dose, compliance with IS 2645 and effect on setting time shall be stated and confirmed by the structural engineer.
All construction joints shall receive cast-in [PVC / rubber waterstop or hydrophilic strip] as detailed. Re-injectable grout tubes shall be cast in at all construction joints, kickers and pile heads. Protection board shall be fixed before backfilling, and backfill placed and compacted in [300] mm layers without damage to the system.
Remedial provision shall be designed in: a Type C drained cavity with accessible sump and pump where Grade 3 is required, or the cast-in injection provision above. The Contractor’s obligation during the defects liability period shall be limited to rectification by the designed remedial means, since re-tanking a raft after construction is not physically possible and injection into a fully bonded sheet is unreliable.
Most common failure. Writing the clause as a membrane item only. Basements leak at construction joints, kickers, pile heads and pipe penetrations far more often than through the field of the membrane. If the waterstop type, the kicker detail and the penetration seal are not named and priced, the membrane contractor is blamed for a joint that was never in his scope — and there is no way to put it right afterwards.
WaterproofingWaterproofing to Toilets, Bathrooms and Sunken Slabs
Sunken and non-sunken wet-area floors, shower walls and adjoining upstands in toilets, bathrooms, kitchens, balconies and utility areas, executed before filling and tiling.
The Contractor shall complete and pressure-test all concealed plumbing before waterproofing. The sunken portion shall be cleaned and the slab, haunches and pipe surrounds made good with polymer-modified mortar; a [75] mm coved fillet shall be formed at all floor-to-wall junctions.
A [two-component polymer-modified cementitious / liquid-applied] membrane shall be applied in not less than [two] coats laid at right angles to a total dry film thickness of not less than [X] mm, carried up all walls not less than [300] mm and not less than [1800] mm within shower zones, and dressed into floor traps and around pipe sleeves with reinforcing fabric at every corner and penetration. Where the membrane is to receive ceramic tiling directly, it shall comply with EN 14891 or equivalent and shall be compatible with the specified tile adhesive.
The completed membrane shall be ponded with not less than [50] mm of water for [24] hours and the soffit below inspected before filling or screeding.
Sunken filling shall be [state material: lightweight free-draining fill / approved granular fill], placed to [X] maximum dry density at the stated moisture condition and compacted in layers. Broken brick, debris and site spoil shall not be used. Secondary drainage shall be provided at membrane level: a weep or drain at the lowest point of the sunken zone discharging into the floor trap above the water seal, fitted with a filter against blockage, so that water passing the tiling has a route out rather than standing permanently on the membrane.
Most common failure. Waterproofing before the plumbing is finally tested and fixed, and leaving the fill to another document. Every later chase or trap relocation cuts the membrane, and the patch rarely gets the fabric reinforcement the original corner had. Brickbat and debris fill holds water indefinitely over a membrane that then sits under a permanently saturated mass. Make plumbing sign-off the hold point that releases the waterproofing, specify the fill here, and give the water a way out.
WaterproofingInternal Lining and Waterproofing of Water-Retaining Structures
RCC underground and overhead water tanks, sumps, reservoirs, STP and ETP structures, including surfaces in contact with potable water or effluent.
The structure shall be designed and constructed to IS 3370 with the specified cover and crack-width limits; waterproofing is supplementary and shall not be used to compensate for structural deficiency.
Before lining, the structure shall be hydrostatically tested to IS 3370 (Part 1). The test regime shall state: fill rate in metres of depth per 24 hours; the stabilisation period after filling before readings begin, since concrete absorbs water for several days; the measurement period; the permissible drop expressed against water depth; and mandatory correction for evaporation and rainfall using a floating reference vessel or covered pan read over the same period. An uncorrected reading is not acceptable — in NCR between April and June, open-surface evaporation can exceed the entire permissible drop within a day.
Construction joints shall carry cast-in waterstops, and any seepage shall be arrested by [crystalline / polyurethane] injection before lining. Internal surfaces shall be cleaned of laitance and form-release agent.
Substrate condition shall follow the system specified. Cementitious and crystalline linings shall be applied to a saturated surface-dry substrate with no free water, in [two] coats to a total thickness of not less than [X] mm. Epoxy linings shall be applied only to a substrate dry to the supplier’s stated limit, verified by in-situ relative humidity, with no application where there is moisture drive from the far face, to a total dry film thickness of not less than [X] microns. Fabric reinforcement shall be used at corners and penetrations. The supplier shall confirm in writing that the product suits permanent immersion in the stored liquid at the stated temperature.
Materials in contact with potable water shall carry NSF/ANSI 61 certification, WRAS approval, or equivalent potable-water approval evidenced by a current certificate from an accredited body, subject to the Engineer’s acceptance. The certificate shall be current at the date of supply, shall cover the product in the form and thickness applied, and shall be submitted with the material approval. The lined structure shall be re-tested, flushed and disinfected before handover.
Most common failure. Calling for a saturated surface-dry substrate and then offering an epoxy option in the same sentence. SSD is right for cementitious and crystalline linings and exactly wrong for epoxy — water trapped at the bond line blisters it osmotically, usually within weeks of first filling. The thickness unit gives the mistake away: an epoxy tank lining is specified in microns, a cementitious one in millimetres.
Industrial FlooringEpoxy Resin Floor Coating and Self-Levelling Epoxy Screed
Internal concrete floors in warehouses, production halls, workshops, laboratories and pharmaceutical areas requiring a jointless, cleanable and chemically resistant resin finish. Car park and exposed decks are excluded — see the note below.
The Contractor shall prepare the concrete substrate by [shot-blasting / diamond grinding] to remove laitance and contamination and to expose a sound, open profile of [CSP 3 to 5] to ICRI 310.2R.
Substrate tensile strength shall be not less than [1.5] N/mm2 measured to ASTM C1583, with failure required within the concrete at or above the stated value; adhesive failure at the primer line is not acceptable. The number of tests, location sampling and failure-mode acceptance shall be stated and entered into the method statement before testing starts.
Residual moisture shall be within the system supplier’s stated limits. The site check shall be a carbide (CM) meter reading backed by the polythene sheet screening test to ASTM D4263. Where the tender specifies instrument testing, in-situ relative humidity to ASTM F2170 or moisture-vapour emission to ASTM F1869 shall be booked with the testing agency in advance — both need drilled sleeves, calibrated instruments and an equilibration or conditioning period and cannot be arranged on the morning of application. Where limits are exceeded, a moisture-tolerant primer or damp-proof membrane shall be applied.
Cracks and blowholes shall be routed, filled and levelled with resin mortar, and perimeter and movement joints shall be cut through the system and sealed. The system shall comprise primer, [body coat / self-levelling screed] and [seal coat] to a total dry thickness of not less than [X] mm.
Slip resistance shall be specified by area and duty: not less than [R11] to DIN 51130 (shod ramp test with lubricant) for working areas, and where wet barefoot areas exist the class shall be stated separately to DIN 51097 (classes A, B or C). The aggregate broadcast rate and grade required to achieve the stated value shall be specified, together with the cleanability requirement, since the two pull against each other. An approved sample area shall be laid and accepted before bulk application.
Environmental limits: ambient and substrate temperature shall be within the named product’s stated range for mixing and application; the substrate shall be not less than 3 degC above dew point during application and until touch-dry. Substrate temperature, air temperature, relative humidity and dew point shall be recorded at the start of each shift and at every material change. Where substrate temperature approaches the upper limit, batch sizes shall be reduced and material and mixing water conditioned, or work moved to the cooler part of the day.
Acceptance shall be on measured thickness, pull-off adhesion to ASTM C1583, full cure, and absence of pinholes, blisters and delamination.
Most common failure. Keeping car parks inside an epoxy clause. A rigid epoxy coating or self-levelling screed is the wrong system for a deck that moves thermally, cracks, and takes point loads and tyre scuffing — the cracks come back through the coating in the first summer. Specify a separate crack-bridging deck coating with stated crack-bridging class, elongation, wear course, wet slip resistance and UV stability, and where the deck is the roof of occupied space, say which system provides the waterproofing.
Industrial FlooringHeavy-Duty Cementitious Polyurethane Flooring to Wet and Food-Processing Areas
Floors in dairies, breweries, food and beverage processing, cold stores, commercial kitchens and wash-down bays subject to thermal shock, steam cleaning, organic acids and constant wetting.
The Contractor shall shot-blast the substrate to expose sound aggregate at a surface profile of [CSP 4 to 6] to ICRI 310.2R and shall cut anchor grooves not less than [6] mm wide by [6] mm deep at all perimeters, doorways, drain edges and terminations.
Substrate tensile strength shall be not less than [1.5] N/mm2 measured to ASTM C1583, with failure within the concrete; the substrate may be damp within the limits stated by the system supplier.
A trowel- or screed-applied cementitious polyurethane system shall be laid to a thickness of not less than [X] mm, stated by duty rather than as a single figure for the whole floor, where the area is subject to steam cleaning, thermal shock or heavy impact.
Slip resistance shall be not less than [R11] to DIN 51130 — the ramp test for workrooms and working areas walked in footwear, carried out with lubricant. Where wet barefoot areas exist (change rooms, showers, wash-down zones) the class shall be specified separately to DIN 51097 as A, B or C. The requirement shall be shown on the drawing schedule area by area.
Coving not less than [100] mm high shall be formed at all wall, plinth and equipment-base junctions and dressed into drainage channels.
Falls to drains of not less than [1 in 80] shall be formed in the structural slab or in a separately measured and priced levelling screed, compatible with and bonded under the topping, laid to the stated fall and cured before the topping is laid. Falls cannot be formed in a 6 to 9 mm topping, which follows whatever it is laid on. The fall shall be a pre-installation hold point verified by level survey and recorded, and a post-completion drainage check shall show no residual pool exceeding [3] mm depth after [30] minutes.
Environmental limits: ambient and substrate temperature shall be within the named product’s stated range for mixing and application; the substrate shall be not less than 3 degC above dew point during application and until touch-dry. Substrate temperature, air temperature, relative humidity and dew point shall be recorded at the start of each shift and at every material change. Where substrate temperature approaches the upper limit, batch sizes shall be reduced and material and mixing water conditioned, or work moved to the cooler part of the day.
Materials shall be non-tainting and suitable for food-processing environments.
Most common failure. Specifying one thickness across the whole floor instead of by duty, and letting the anchor groove be value-engineered out. A 4 mm system laid up to a steam-cleaned cook line or a blast-freezer door debonds from thermal shock, and an unterminated edge at a drain or doorway lifts within months. Thickness follows the temperature and wash-down regime; the groove is not optional.
Concrete RepairStructural and Non-Structural Concrete Repair to EN 1504 Principles
Repair of spalled, delaminated and carbonation- or chloride-damaged reinforced concrete in buildings, bridges, industrial structures and marine or coastal exposure.
The Contractor shall carry out a condition survey recording delamination, cover, carbonation depth, chloride content and half-cell potential, and shall agree the repair principle and method to EN 1504-9 with the Engineer before work begins. The survey outcome, not the visible spalling, defines the repair area.
A covermeter survey shall be carried out and bar positions marked before any saw-cutting. Saw-cut depth shall be capped at [10] mm and shall not be taken through cover to reinforcement. Defective concrete shall be removed by [pneumatic breaking / hydro-demolition] to sound substrate and not less than [20] mm behind exposed reinforcement; edges shall be cut square, and feather edges are not permitted. Breaker class shall not exceed the [7] kg class within [150] mm of a reinforcing bar, and breaking along or directly on to a bar is prohibited.
Corroded reinforcement shall be cleaned to St 3 to ISO 8501-1 by hand or power tool where the bar is embedded and cleaned in situ; Sa 2.5 shall be specified only where the bar can be fully exposed and blast-cleaned. Reinforcement shall be replaced where section loss exceeds [10] per cent, with laps as detailed; supplementary bar is a design decision. Reinforcement protection coating and bonding primer shall be applied where specified, within their stated overcoat window.
Where the survey diagnoses chloride-induced corrosion, patch repair with an EN 1504-3 mortar alone is not acceptable. The corresponding EN 1504-9 method shall be specified and separately priced: discrete galvanic (sacrificial) anodes at and around repair perimeters as designed, impressed-current cathodic protection, or removal of chloride-contaminated concrete to a stated chloride threshold rather than to visible spalling.
Repair mortar shall be a [polymer-modified cementitious / low-shrinkage flowable] product classified to EN 1504-3 Class [R3 / R4], applied within the stated layer thickness and wet-cured for not less than [3] days. Acceptance shall be by tapping survey and pull-off testing to EN 1542.
Most common failure. Repairing only what is visibly spalled. Where the sound-looking cover alongside is already carbonated or chloride-contaminated, the new alkaline patch sets up an incipient anode and fresh spalling appears at the repair perimeter within a year. Note also that IS 13311 (Parts 1 and 2) : 1992 are withdrawn — the methods are now IS 516 (Part 5). Both old numbers are still widely quoted in Indian tenders and CPWD documents, so where a client’s tender calls up IS 13311, quote the current designation alongside it rather than substituting silently.
Grouts & AnchorsNon-Shrink Cementitious Grouting to Base Plates, Machine Bases and Bolt Pockets
Grouting beneath structural steel base plates, static equipment and machine bases, crane rails and sole plates, and filling of holding-down bolt pockets.
The Contractor shall use a pre-bagged non-shrink cementitious grout of characteristic compressive strength not less than [X] N/mm2 at [28] days, exhibiting no net shrinkage after set.
The foundation concrete shall have attained its specified strength; the surface shall be roughened to expose aggregate, cleaned of oil, laitance and debris, and saturated for not less than [12] hours with free water removed immediately before grouting. Formwork shall be leak-tight, with a head box on the pouring side maintaining a head of not less than [100] mm. Minimum grout thickness beneath the plate shall be [X] mm, with air-release vents of [X] mm diameter at not more than [X] mm centres at all high points.
Base plates shall be set to level on shims or levelling nuts. For structural steel base plates, shims may remain in place unless shown otherwise. For machine and equipment bases, shims and levelling devices shall be slackened or removed once the grout attains [X] N/mm2, and the resulting voids filled with the same grout in a recorded second operation — shims left under a rotating or vibrating machine create hard bearing points and defeat the uniform bearing the grout exists to provide.
Grout shall be mechanically mixed at the stated water content, measured into the mixer with a calibrated measure, and poured continuously from one side only until it emerges at all remaining edges. Grouting of each plate shall be completed in a single operation.
Flow shall be verified on each batch by flow cone to ASTM C939, against a stated acceptance efflux time range, with a re-test after [X] minutes to confirm retained flow over the time the pour actually takes.
Test specimens shall match the standard the strength is declared against: where the grout is specified to ASTM C1107, 50 mm cubes tested to ASTM C109. The number of specimens per batch or per base plate, the curing regime and the acceptance criterion shall be stated. The grout shall be cured and protected for [3] days.
Environmental limits: ambient and substrate temperature shall be within the named product’s stated range for mixing and application; the substrate shall be not less than 3 degC above dew point during application and until touch-dry. Substrate temperature, air temperature, relative humidity and dew point shall be recorded at the start of each shift and at every material change. Where substrate temperature approaches the upper limit, batch sizes shall be reduced and material and mixing water conditioned, or work moved to the cooler part of the day.
Most common failure. Adding water on site to make the grout flow, and testing 150 mm concrete cubes of a fine-aggregate grout. Non-shrink grout loses strength and starts to bleed and shrink the moment the water/powder ratio is exceeded, and voids form under the plate. A 150 mm cube result also cannot be compared with a strength declared against 50 mm specimens, so the test proves nothing either way. Measure water into the mixer, run flow-cone checks on each batch, and never allow a plate to be grouted in two pours.
Grouts & AnchorsEpoxy Resin Grouting to Dynamically Loaded and Chemically Exposed Machine Bases
Grouting of base plates and machine bases subject to vibration, impact or dynamic loading, chemically exposed bases, and thin-section grouts where cementitious grout is unsuitable.
The Contractor shall use a three-component epoxy resin grout of compressive strength not less than [X] N/mm2.
The design bearing pressure and the maximum sustained service temperature shall be stated together, and the supplier shall provide creep data at that temperature and stress. Creep in an epoxy grout is as much a function of temperature as of load: a grout that performs at 25 degC can creep significantly at the 45 to 55 degC found under a running machine or in an uncooled Indian plant room. A minimum heat deflection temperature to ASTM D648 shall be specified with a stated margin above the maximum service temperature.
The foundation shall be mechanically prepared to a sound, dry and oil-free condition; epoxy grout shall not be placed on damp or contaminated concrete and no pre-wetting is permitted. Base-plate surfaces in contact with grout shall be degreased and free of loose scale, and surfaces to remain uncoated shall be masked. Formwork shall be sealed and lightly waxed, with expansion gaps and chamfers formed at re-entrant corners.
Components shall be mixed in complete units only; part-mixing is not permitted. Grout shall be poured from one side to displace air. The maximum layer thickness in a single pour, the clearance beneath the plate, and the maximum ambient and substrate temperature at which the grout may be placed shall be stated and observed. Cured grout shall be checked for full contact by tapping.
Environmental limits: ambient and substrate temperature shall be within the named product’s stated range for mixing and application; the substrate shall be not less than 3 degC above dew point during application and until touch-dry. Substrate temperature, air temperature, relative humidity and dew point shall be recorded at the start of each shift and at every material change. Where substrate temperature approaches the upper limit, batch sizes shall be reduced and material and mixing water conditioned, or work moved to the cooler part of the day.
Most common failure. Part-mixing the kit and pouring deeper than allowed. The aggregate is graded for the full unit, so splitting a pack changes the ratio; and epoxy is exothermic, so an over-deep pour heats up and cracks as it cools. Fix the design bearing pressure AND the service temperature in the clause — creep at temperature, not compressive strength, is what governs an epoxy grout under sustained load.
Sealants & JointsSealing of Expansion, Contraction and Movement Joints
Expansion, contraction, isolation and construction movement joints in floors, walls, terraces, water-retaining structures and paved areas, including joints subject to trafficking or immersion.
Joint width shall be calculated from the design thermal and shrinkage movement divided by the selected sealant’s movement accommodation factor, and shall be shown on the drawings. A joint too narrow for its movement will fail whatever sealant is put in it.
The sealant shall be selected and named by exposure, not offered as an open menu: trafficked horizontal, permanently immersed, fuel or chemical exposure, and potable-water contact — the last requiring a current potable-water approval as in the water-retaining structures clause. Movement accommodation factor shall be not less than [+/-25] per cent.
Joint faces shall be clean, dry, sound and free of laitance, curing compound and previous sealant; damaged arrises shall be made good before sealing. Sealant shall be applied over a closed-cell polyethylene backer rod or bond-breaker tape so that adhesion is to two faces only; three-sided adhesion is not permitted. Backer rod diameter shall be approximately [25] per cent oversize to joint width.
Sealant depth shall follow ASTM C1193 and shall be tabulated on the drawings against joint width so the site has no discretion: for joints from about 6 mm to 12 mm wide, sealant depth equal to the joint width with a minimum of 6 mm; for joints wider than 12 mm, depth equal to half the width, capped at about 12 to 13 mm regardless of width. The width tolerance beyond which the detail must be referred back shall be stated.
Primer shall be used where required for the substrate. Sealant shall be gun-applied and tooled to a concave profile free of voids. Adhesion shall be verified by hand-pull test to ASTM C1193 on [X] locations per [100] m, carried out after the sealant has reached the cure state the test requires, not on the day of application.
Environmental limits: ambient and substrate temperature shall be within the named product’s stated range for mixing and application; the substrate shall be not less than 3 degC above dew point during application and until touch-dry. Substrate temperature, air temperature, relative humidity and dew point shall be recorded at the start of each shift and at every material change. Where substrate temperature approaches the upper limit, batch sizes shall be reduced and material and mixing water conditioned, or work moved to the cooler part of the day.
Most common failure. Three-sided adhesion, and a depth rule that fights itself. Where the backer rod is left out and the sealant bonds to the joint base as well as the two faces, it cannot extend and tears at the first thermal cycle — this single omission accounts for most sealant failures on terraces and podium decks. And a blanket ’10 mm minimum’ applied to a 12 mm joint forces a depth-to-width ratio near 1:1 where 2:1 was intended, over-stiffening the sealant and reducing the movement it can actually take.
Protective CoatingsAnti-Carbonation Protective Coating to Exposed Concrete
Exposed RCC surfaces of bridges, flyovers, chimneys, facades, water-retaining structures and coastal or industrial buildings, applied to slow carbonation and reduce water and chloride ingress.
Carbonation depth (phenolphthalein indicator on freshly broken cores) and cover shall be measured and mapped before any coating is specified or applied. Where carbonation has reached, or is within [10] mm of, the reinforcement, an anti-carbonation coating alone is not acceptable: the area shall pass to the concrete repair clause for cover replacement, realkalisation or an EN 1504-9 electrochemical method, with the coating applied afterwards. A coating slows further ingress; it does not restore passivity to steel the carbonation front has already reached, and applying one over a carbonated cover zone seals the condition in.
The Contractor shall apply an anti-carbonation protective coating system complying with EN 1504-2, Principles 1 and 2. Defective concrete shall be repaired and cracks treated before coating; the surface shall be cleaned, blowholes filled with a levelling mortar, and new concrete allowed to cure for not less than [28] days.
The system shall comprise primer and not less than [two] finish coats applied by [brush / roller / airless spray] to a total dry film thickness of not less than [X] microns, verified by wet film gauge readings converted using the declared volume solids, by recorded consumption per m2 against a marked grid, and by dry film measurement on witness panels retained until handover.
The Contractor shall submit independent test certificates showing carbon dioxide diffusion resistance equivalent to not less than [50] m of air, water vapour transmission [Class I], liquid water permeability not exceeding [0.1] kg/m2.h^0.5, and pull-off adhesion not less than [0.8] N/mm2 to EN 1542. A sample panel shall be approved before bulk application.
Environmental limits: ambient and substrate temperature shall be within the named product’s stated range for mixing and application; the substrate shall be not less than 3 degC above dew point during application and until touch-dry. Substrate temperature, air temperature, relative humidity and dew point shall be recorded at the start of each shift and at every material change. Where substrate temperature approaches the upper limit, batch sizes shall be reduced and material and mixing water conditioned, or work moved to the cooler part of the day.
Most common failure. Measuring the work in coats and litres instead of microns, and coating a carbonated cover zone because the concrete still looks sound. Carbonation resistance is a direct function of achieved dry film thickness, so a two-coat job applied thin performs like decorative paint while passing a visual inspection. And on the existing bridges and chimneys this clause is written for, the carbonation front has usually already reached the steel — survey first, then decide whether a coating is the right answer at all.
Codes and standards
The reference table, filtered
Indian codes first, with the European and American standards the industry genuinely cites here. Anything our reviewers could not stand behind was removed rather than softened; where a number or year is uncertain it is marked, not hidden.
| Code | Title | Subject | What it governs |
|---|---|---|---|
| IS 1786:2008 | High Strength Deformed Steel Bars and Wires for Concrete Reinforcement — Specification | Reinforcement | Specifies grades Fe 415, Fe 500, Fe 550 and Fe 600 with chemical and mechanical limits — the reference for any replacement or supplementary reinforcement installed during a structural repair. The D (higher ductility) and S (earthquake-resistant) variants are NOT available across all grades: S is not defined for Fe 550, and Fe 600 carries neither variant, so a clause calling for ‘Fe 550S to IS 1786’ cannot be supplied. |
| IS 383:2016 | Coarse and Fine Aggregate for Concrete — Specification | Concrete — materials | Specifies grading, deleterious content and acceptance limits for aggregates, including manufactured sand and recycled aggregate; cited when a repair micro-concrete or grout is to be site-extended with aggregate. |
| IS 456:2000 | Plain and Reinforced Concrete — Code of Practice | Concrete — general | The base code for design, materials, workmanship and durability of RCC in India, including exposure classes, minimum cement content, maximum water-cement ratio and cover — every waterproofing or repair specification ultimately has to sit consistently with it. |
| IS 9103:1999 | Concrete Admixtures — Specification | Concrete admixtures | Defines the categories of chemical admixture (accelerating, retarding, water-reducing, superplasticising, air-entraining) and the performance limits an admixture must meet against a control mix; the clause a tender cites when calling for a plasticiser or superplasticiser. |
| EN 1504-1 | Products and Systems for the Protection and Repair of Concrete Structures — Definitions | Concrete repair | Establishes the vocabulary and product-family definitions used across the EN 1504 series, so that terms such as repair mortar, surface protection system and bonding agent mean the same thing in a submittal as in the specification. |
| EN 1504-10 | Products and Systems for the Protection and Repair of Concrete Structures — Site Application of Products and Systems and Quality Control of the Works | Concrete repair — execution | Governs substrate preparation, application conditions and site quality control for repair works; the part to cite when the dispute is about workmanship and acceptance rather than material conformity. |
| EN 1504-3 | Products and Systems for the Protection and Repair of Concrete Structures — Structural and Non-structural Repair | Concrete repair | Classifies repair mortars into classes R1 to R4 by compressive strength, bond and related properties; the single most-cited clause in Indian repair tenders when specifying a structural (R3/R4) versus non-structural (R1/R2) mortar. |
| EN 1504-5 | Products and Systems for the Protection and Repair of Concrete Structures — Concrete Injection | Crack injection | Governs injection products for cracks, voids and interstices, distinguishing force-transmitting, ductile and swelling-type injection; cited when specifying epoxy or polyurethane injection for structural cracks or water ingress. |
| EN 1504-7 | Products and Systems for the Protection and Repair of Concrete Structures — Reinforcement Corrosion Protection | Corrosion protection of reinforcement | Governs coatings applied to exposed reinforcement during repair to protect it against corrosion — the clause behind the zinc-rich or epoxy rebar primer step in a patch-repair sequence. |
| EN 1504-9 | Products and Systems for the Protection and Repair of Concrete Structures — General Principles for the Use of Products and Systems | Concrete repair | Sets out the repair and protection principles and their methods, which is how a competent repair specification is structured — diagnose the cause, choose the principle, then choose the product, rather than starting from a product name. |
| IS 13620:1993 | Fusion Bonded Epoxy Coated Reinforcing Bars — Specification | Corrosion protection of reinforcement | Covers FBE-coated rebar — coating thickness, adhesion, holiday limits and handling damage — cited in aggressive-exposure and coastal projects where coated reinforcement is specified instead of, or alongside, an applied corrosion-inhibiting system. |
| IS 9077:1979verify edition | Code of Practice for Corrosion Protection of Steel Reinforcement in RB and RCC Construction | Corrosion protection of reinforcement | Sets out protective measures for reinforcement against corrosion in reinforced brickwork and RCC; a useful Indian reference when justifying an inhibitor, coating or cover-based strategy in a repair specification. |
| ASTM C1107 | Standard Specification for Packaged Dry, Hydraulic-Cement Grout (Nonshrink) | Non-shrink grouts | Defines non-shrink cementitious grout by grade (based on whether volume change is measured before or after hardening) and its strength requirements; the reference almost universally cited in Indian machine-foundation and base-plate grouting specifications. |
| ASTM D648 | Standard Test Method for Deflection Temperature of Plastics Under Flexural Load in the Edgewise Position | Grouts and anchors | Heat deflection temperature. Relevant because creep in an epoxy grout is as much a function of temperature as of stress: a grout that performs at 25 degC can creep significantly at the 45 to 55 degC found under a running machine or in an uncooled Indian plant room. Specify HDT with a margin above maximum sustained service temperature. |
| EN 1504-6 | Products and Systems for the Protection and Repair of Concrete Structures — Anchoring of Reinforcing Steel Bar | Anchoring and dowelling | Covers anchoring products for reinforcing bar fixed into hardened concrete — the part reached for when rebar dowels are being chemically anchored into an existing structure. |
| ASTM C779/C779M | Standard Test Methods for Abrasion Resistance of Horizontal Concrete Surfaces | Industrial flooring | Covers abrasion resistance of horizontal concrete and topping surfaces; commonly referenced when a floor hardener or wearing screed is specified for warehouse or industrial traffic. It contains three distinct procedures (revolving disk, dressing wheel, ball bearing) — hence ‘Test Methods’ plural — and the result depends heavily on which is chosen, so state the procedure and not just the designation. |
| DIN 51097 | Testing of Floor Coverings — Determination of the Anti-Slip Property — Wet Barefoot Areas — Walking Method — Ramp Test | Industrial flooring | The WET BAREFOOT ramp test, producing classes A, B and C. This is the standard for change rooms, showers and wash-down zones. R-values do not apply to it, so where a floor has both shod and barefoot wet areas, the two requirements are specified separately and shown area by area on the drawing schedule. |
| DIN 51130 | Testing of Floor Coverings — Determination of the Anti-Slip Property — Workrooms and Working Areas with Slip Danger — Walking Method — Ramp Test | Industrial flooring | The SHOD ramp test, carried out with oil, producing the R9 to R13 classification. It is not a barefoot test and not a water test — ‘wet slip resistance of not less than R11’ mixes two different regimes and demands an R-value under conditions that do not produce one. |
| ICRI 310.2R | Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, Polymer Overlays and Concrete Repair | Industrial flooring | The CSP 1 to 10 concrete surface profile scale, with moulded comparator chips held against the prepared surface. Thicker system, coarser profile — roughly CSP 1-3 for thin coats, 3-5 for self-levelling, 5-9 for trowelled screeds and heavy-duty overlays. |
| IS 4443:1980verify edition | Code of Practice for Use of Resin Type Chemical Resistant Mortars | Chemical-resistant construction | Governs application of resin-based chemical-resistant mortars — surface preparation, mixing, joint width and curing — and is cited alongside the material specification when acid-resistant tiling is being laid. |
| IS 4832verify edition | Chemical Resistant Mortars — Specification | Chemical-resistant construction | Covers chemical-resistant mortars in parts by binder family (including silicate, sulphur and resin types); used when specifying acid-resistant tile bedding and jointing in effluent plants, battery rooms and process areas. |
| EN 1062-3 | Paints and Varnishes — Determination of Liquid Water Permeability | Protective coatings — concrete | Liquid water transmission rate in kg/m2.h^0.5 — quoted alongside CO2 resistance and vapour transmission class in an EN 1504-2 submittal. |
| EN 1062-6 | Paints and Varnishes — Determination of Carbon Dioxide Permeability | Protective coatings — concrete | CO2 diffusion resistance, expressed as an equivalent thickness of air. The property that makes an anti-carbonation coating anti-carbonation, and the figure to demand a certificate for rather than accept on a brochure. |
| EN 1062-7 | Paints and Varnishes — Coating Materials and Systems for Exterior Masonry and Concrete — Determination of Crack Bridging Properties | Protective coatings — concrete | Static and dynamic crack-bridging classification, used to classify coatings under EN 1504-2. The dynamic method exists precisely for cracks that move under thermal cycling, so the common site rule that live cracks are never coated is too absolute — they are not coated with a STATIC system. |
| EN 1504-2 | Products and Systems for the Protection and Repair of Concrete Structures — Surface Protection Systems for Concrete | Protective coatings — concrete | Governs hydrophobic impregnations, impregnations and coatings for concrete, with performance requirements for carbonation resistance, water vapour permeability and capillary absorption — the part cited when calling for an anti-carbonation coating. |
| EN ISO 7783 | Paints and Varnishes — Determination of Water-Vapour Transmission Properties | Protective coatings — concrete | Water vapour transmission class (I, II, III). A concrete coating has to breathe outwards while resisting CO2 and liquid water inwards, so this is specified together with the other two and not instead of them. |
| IS 9862:1981verify edition | Ready Mixed Paint, Brushing, Bituminous, Black, Lead-free, Acid, Alkali, Water and Heat Resisting — Specification | Protective coatings | Specifies the black bituminous protective paint commonly called for on buried concrete faces, plinth beams and below-ground masonry as a damp-proofing coat. |
| ISO 12944 (Parts 1 to 9) | Paints and Varnishes — Corrosion Protection of Steel Structures by Protective Paint Systems | Protective coatings — steel | The multi-part standard defining corrosivity categories and matching paint systems with expected durability ranges. Since the 2017 revision the categories are C1 to C5 PLUS CX (extreme, for offshore and extreme industrial exposure), and the immersion categories run Im1 to Im4, Im4 covering immersion with cathodic protection. A clause written from ‘C1 to C5’ alone leaves an offshore or heavy-marine steelwork specification with no category to select, and will under-specify the system. |
| ISO 8501-1 | Preparation of Steel Substrates before Application of Paints and Related Products — Visual Assessment of Surface Cleanliness | Protective coatings — steel | Blast grades Sa 1 to Sa 3 and hand and power tool grades St 2 and St 3. Note that Sa 2.5 is effectively unachievable in situ on the back face of an embedded reinforcing bar, so a repair clause should specify St 3 for in-situ bar cleaning and reserve Sa 2.5 for bars that can be fully exposed and blast-cleaned. |
| IS 12200:2001verify edition | Provision of Water Stops at Transverse Contraction Joints in Masonry and Concrete Dams — Code of Practice | Joints and water stops | Governs provision and installation of water stops at joints in mass concrete and masonry hydraulic structures; a usable Indian reference for water bar detailing, though its scope is dam-focused rather than general building. |
| EN 1504-4 | Products and Systems for the Protection and Repair of Concrete Structures — Structural Bonding | Structural strengthening | Covers structural bonding agents, including adhesives used to bond plates and laminates to concrete, and is the reference behind epoxy adhesives used in plate bonding and FRP strengthening. |
| IS 13935:2009verify edition | Seismic Evaluation, Repair and Strengthening of Masonry Buildings — Guidelines | Structural strengthening | Provides guidance on evaluating and retrofitting masonry buildings, including grouting of cracks, stitching and jacketing; the Indian reference most often cited on masonry retrofit tenders. |
| IS 1893 (Part 1):2016 | Criteria for Earthquake Resistant Design of Structures — General Provisions and Buildings | Structural design | Defines seismic zones, design spectra and load combinations, and is the governing document a strengthening scheme (jacketing, FRP wrapping, bracing) must be demonstrated against before any product is selected. |
| ASTM C109 | Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 50 mm Cube Specimens) | Testing — grouts | The method a pre-bagged grout’s declared strength is actually derived from. Testing 150 mm concrete cubes of a fine-aggregate grout to IS 516 gives a number that cannot be compared with the declared figure, which is why the specimen size has to match the standard the strength is declared against. |
| ASTM C1583 | Standard Test Method for Tensile Strength of Concrete Surfaces and the Bond Strength or Tensile Strength of Concrete Repair and Overlay Materials by Direct Tension (Pull-off Method) | Testing — repair and coatings | The pull-off test used to verify bond of a repair mortar, overlay or coating to the substrate, and the correct method to name in a specification when a minimum pull-off value is being demanded at site. |
| ASTM C827 | Standard Test Method for Change in Height at Early Ages of Cylindrical Specimens of Cementitious Mixtures | Testing — grouts | Measures early-age height change of a cementitious mixture, and is the method behind the plastic-state expansion figure quoted on non-shrink grout datasheets — worth naming in a tender so the claimed expansion is measured consistently. |
| ASTM C876 | Standard Test Method for Corrosion Potentials of Uncoated Reinforcing Steel in Concrete | Testing — repair and coatings | Half-cell potential survey. Identifies actively corroding areas well beyond the visibly spalled zone, which is why the survey and not the eye defines the repair quantity — and why patch-repairing only what has spalled produces a ring of new spalling a year later. |
| ASTM C939 | Standard Test Method for Flow of Grout for Preplaced-Aggregate Concrete (Flow Cone Method) | Testing — grouts | Flow cone efflux time — the site check that catches water being added to a non-shrink grout to make it flow. Specify an acceptance range and a re-test after a stated interval, so retained flow over the time the pour actually takes is proved and not assumed. |
| ASTM D4541 | Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers | Protective coatings — testing | The portable adhesion test for a COATING on its substrate — epoxy, polyurethane or other protective system. It is NOT the method for the tensile strength of a prepared concrete surface or the bond of an overlay to it: that is ASTM C1583. Specifying a substrate acceptance value against D4541 cites a standard for something it does not govern, and hands the contractor an argument at the first failed dolly. |
| ASTM D5957 | Standard Guide for Flood Testing Horizontal Waterproofing Installations | Testing — waterproofing membranes | Flood-test practice. Note it is a GUIDE: the water depth, duration, outlet plugging, bay sub-division on a deck laid to falls, and the structural check on the imposed load all have to be written into the clause, or the test proves nothing over most of the area. |
| EN 1542 | Products and Systems for the Protection and Repair of Concrete Structures — Test Methods — Measurement of Bond Strength by Pull-off | Testing — repair and coatings | The pull-off method for repair and protection systems on concrete, using partially cored 50 mm dollies. Record the failure mode as well as the load — a 2.0 N/mm2 glue-line failure and a 1.4 N/mm2 concrete failure mean opposite things. |
| IS 1199 | Fresh Concrete — Methods of Sampling, Testing and Analysis | Testing — concrete | Governs sampling of fresh concrete and workability measurement (slump, flow, compacting factor), which is the reference needed when an admixture is claimed to hold slump for a stated period; issued in multiple parts, so verify the part number. |
| IS 13630 (Parts 1 to 15)verify edition | Ceramic Tiles — Methods of Test, Sampling and Basis for Acceptance | Testing — tiling | The multi-part test code for ceramic tiles covering dimensions, water absorption, modulus of rupture, chemical resistance and stain resistance; Part 15 is itself the sampling and acceptance part. Several parts were revised in 2019 while others remain at 2006, so cite the part together with its year. |
| IS 13826 (Parts 1 to 8)verify edition | Bitumen Based Felts — Methods of Test | Testing — waterproofing membranes | Provides the test methods (breaking strength, pliability, heat resistance, water absorption and similar) applied to bitumen-based felts. These were written around the hessian- and fibre-base felts of IS 1322, and BIS has no product specification for APP or SBS polymer-modified bituminous membranes — so a submittal for a modern torch-applied membrane is not actually governed by it. Require the membrane’s own declared properties and a product standard such as EN 13707. |
| IS 3025 | Methods of Sampling and Test (Physical and Chemical) for Water and Wastewater | Testing — water | The multi-part code used to test water for concreting and curing against the limits in IS 456, and the reference used when a project must demonstrate that site water is fit for mixing. |
| IS 4031 | Methods of Physical Tests for Hydraulic Cement | Testing — cement | The multi-part code governing consistency, setting time, soundness, fineness and strength testing of cement, and the reference behind most acceptance testing of cementitious repair mortars and grouts at the site laboratory. |
| IS 516 | Methods of Tests for Strength of Concrete | Testing — concrete | Prescribes how compressive, flexural and related strength specimens are made, cured and tested, so that a strength figure quoted in a submittal or a site cube result is defensible; now issued in parts, so confirm the current part and year before citing it in a clause. |
| IS 516 (Part 5/Sec 1) | Hardened Concrete — Methods of Test — Non-destructive Testing: Ultrasonic Pulse Velocity | Testing — concrete | UPV for concrete quality, uniformity and crack depth. This replaces IS 13311 (Part 1) : 1992, which is WITHDRAWN but still widely quoted in Indian tenders and CPWD documents — where a client’s tender calls up the old number, quote the current designation alongside it rather than substituting silently. |
| IS 516 (Part 5/Sec 4):2020 | Hardened Concrete — Methods of Test — Non-destructive Testing: Rebound Hammer | Testing — concrete | Rebound hammer screening of surface hardness. Replaces IS 13311 (Part 2) : 1992, also withdrawn. Screening only — confirm by extracted cores where readings are marginal or disputed. |
| IS 15477:2019 | Adhesives for Use with Ceramic, Mosaic and Stone Tiles — Specification | Tile adhesives and installation | The 2019 First Revision is a PRODUCT specification for tile adhesives — requirements, classification and test methods. The table previously carried the superseded 2004 title, ‘Specification for Laying of Ceramic Tiles Using Adhesives’, against the 2019 year; that edition was a code of practice for laying, and a submittal checked against it is being checked against the wrong document. |
| IS 15622:2017verify edition | Pressed Ceramic Tiles — Specification | Tiling — substrate and tile | Specifies dimensional, water absorption and strength requirements for pressed ceramic tiles by group, which matters to adhesive selection because water absorption and tile size drive the adhesive class and the notch size. |
| BS 8102verify edition | Protection of Below Ground Structures against Water from the Ground — Code of Practice | Waterproofing — general | The Grade 1 to 3 internal environment classification and the Type A (barrier), Type B (structurally integral) and Type C (drained) protection types. A specification that names a Grade without naming the Type has not said how the Grade is to be achieved. |
| EN 13707 | Flexible Sheets for Waterproofing — Reinforced Bitumen Sheets for Roof Waterproofing — Definitions and Characteristics | Waterproofing — bituminous | The product standard for reinforced bituminous roofing membranes. Useful in Indian specifications precisely because BIS has no equivalent for APP and SBS polymer-modified sheets, so without it the membrane’s quality is governed by nothing in the clause. |
| EN 14891 | Liquid Applied Water Impermeable Products for Use beneath Ceramic Tiling — Requirements, Test Methods, Evaluation of Conformity | Waterproofing — general | Wet-area membranes that receive ceramic tiling directly — the standard a bathroom or sunken-slab membrane is normally certified to, and the one to cite alongside the tile adhesive class. |
| IS 1322:1993verify edition | Bitumen Felts for Waterproofing and Damp-proofing — Specification | Waterproofing — bituminous | Specifies types and grades of hessian-based and fibre-based bitumen felt with their physical requirements; what a specifier reaches for when accepting or rejecting a felt roll delivered to site. |
| IS 1346:1991verify edition | Code of Practice for Waterproofing of Roofs with Bitumen Felts | Waterproofing — bituminous | Covers the built-up bitumen felt roof waterproofing system — number of layers, laying sequence and treatment at junctions — and remains the reference for traditional felt treatments in CPWD-type specifications. |
| IS 2645:2003 | Integral Waterproofing Compounds for Cement Mortar and Concrete — Specification | Waterproofing — admixtures | Covers integral waterproofing compounds added at the mixer, setting requirements for permeability reduction, setting time and strength effect relative to a control mix — the code behind the common tender line ‘integral waterproofing compound conforming to IS 2645’. |
| IS 3067:1988verify edition | Code of Practice for General Design Details and Preparatory Work for Damp-proofing and Waterproofing of Buildings | Waterproofing — general | Sets out preparatory and detailing principles for waterproofing work — falls, coving, upstands, protection and substrate preparation — and is the code to cite when the argument on site is about detailing rather than product. |
| IS 3370 | Concrete Structures for Storage of Liquids — Code of Practice | Water-retaining structures | Governs design and construction of liquid-retaining concrete structures — water tanks, STP and ETP tanks, reservoirs — with tighter crack-width and permeability expectations than IS 456; issued in parts covering general requirements, reinforced concrete, prestressed concrete and design tables. |
No standard matches that.
Before work starts
What to check on the substrate
The conditions that decide whether a system will hold. Every figure here is a working range — the product datasheet governs, and where a value varies by product we say so rather than printing one number.
| Check | Typical requirement | How it is measured | Why it matters |
|---|---|---|---|
| Substrate moisture content Epoxy and PU floor coatings and screeds, liquid-applied membranes, tank linings, bonded overlays. Reversed for cementitious waterproof coatings and polymer-modified repair mortars, which need the substrate pre-soaked to SSD. | For solvent-free epoxy and PU systems on concrete, commonly 4-6% moisture by weight and in-situ RH not exceeding 75%. Moisture-tolerant primers and epoxy DPM grades are sold specifically to work above this, some up to 95% RH. Cementitious systems invert the rule and require a saturated surface-dry substrate — visibly damp, no free water, no sheen. There is no universal figure: the limit is a property of the product, the current datasheet governs, and where the tender is silent the manufacturer’s written limit is entered into the method statement before work starts. | SITE DEFAULT: carbide (CM) meter for percentage by weight, backed by the polythene sheet screening test to ASTM D4263 — roughly 450 x 450 mm taped on all four edges for 16 h, checked for condensation or darkening. CM and oven-dry (Darr) do NOT return the same figure for the same concrete — CM runs lower — so test by the method the datasheet states its limit against, and record which was used. LEAD-TIME, TENDER-SPECIFIED ONLY: in-situ RH to ASTM F2170 and moisture-vapour emission to ASTM F1869. Both need instruments, drilled sleeves and an equilibration or conditioning period, and are booked with the testing agency days in advance. Record depth and location of every reading, not a single spot value. | Water driven upward by vapour pressure collects under an impermeable film and lifts it as osmotic blisters, typically weeks after handover, in the middle of bays, with the failed coat coming away wet on the underside. |
| Substrate and ambient temperature Epoxy, PU and MMA coatings and screeds; PU and polysulphide sealants; bituminous and liquid membranes; polymer-modified repair mortars; resin injection. | Most site-applied resin systems quote a window of about 10-35 degC for both substrate and air, with the substrate the governing figure. Winter-grade hardeners extend this to about 5 degC; hot-climate hardeners protect pot life at the top end. Below the stated minimum an epoxy does not simply cure slowly — it may not reach full cross-link at all. Above about 35 degC pot life and open time can halve. Cementitious products have their own window, typically 5-40 degC. The datasheet governs. In Delhi NCR the practical consequence is that May-June work moves to early morning and December-January work needs a low-temperature grade or must wait for the slab to warm. | Calibrated contact (magnetic or probe) thermometer on the substrate itself, at several points including shaded and exposed areas; an infrared gun is acceptable for screening but reads emissivity-dependent and should be checked against a contact reading. Air temperature and humidity by whirling hygrometer or calibrated digital psychrometer (ASTM E337). Record substrate temperature, air temperature, RH and time on the application record. | Applied below the minimum, the film stays soft and under-cross-linked, fails a solvent rub, loses its chemical resistance and prints under wheel loads; applied on a slab at 45 degC in June, the mixed material gels in the bucket before it is laid. |
| Dew point rule All protective coatings on steel and concrete, epoxy and PU floors, liquid-applied membranes, tank and pipe linings. | Substrate temperature at least 3 degC above dew point and rising, checked immediately before application and again through the shift. Many specifications add a ceiling of 85% relative humidity for coating work. This is the one rule on this list close to universal across manufacturers, but products differ on the RH ceiling, so the datasheet still governs. A falling substrate temperature is a stop condition even where the 3 degC margin is momentarily satisfied — that is the standard trap on evening application, where the slab cools through dew point during cure. | Whirling hygrometer or calibrated digital dew point meter for air temperature and RH, from which dew point is read or computed; contact thermometer for substrate temperature; the differential calculated and logged. ISO 8502-4 sets out the method and tables for estimating the probability of condensation before painting. | A film of condensate too thin to see forms on the surface, so the coat is applied to water rather than to the substrate — flash rust under the primer on steel, amine blush on epoxy, and a coat that lifts in sheets at the first pull-off test. |
| Material, batch and pack integrity Every applied system without exception. | The product is the one specified, with no substitution without written approval; within shelf life at the date of use; base and hardener from matched kits, full packs only, mixed in the ratio and by the method on the datasheet — no part-packs, no topping up. Packs unopened, undamaged and stored within the stated temperature range, off the ground, out of sun and rain. The CURRENT datasheet and SDS on site, not a project-old copy. Batch numbers and quantities recorded against the area laid. | Delivery challan checked against batch and lot numbers and manufacture and expiry dates on the packs; calibrated weighing where the ratio is by weight; correct forced-action mixer, paddle and mixing time; batch size set so the mix can be laid inside pot life at the measured substrate temperature. | Every other row in this table defers to ‘the current datasheet’ — this is the row that requires the current datasheet to actually be on site. A consignment past shelf life, a base without its matched hardener, a drum that has stood in June sun or a silent brand substitution stops work as surely as a wet slab, and is the most common avoidable cause of failure on Indian sites. |
| Substrate compressive and pull-off (tensile) strength Resin screeds and self-levelling floors, bonded overlays, repair mortars, structural strengthening, heavy-duty coatings. | For resin flooring and bonded overlays a common floor is 25 N/mm2 substrate compressive strength and 1.5 N/mm2 surface tensile (pull-off) strength, with failure required in the concrete rather than at the glue line. Repair mortar classes under EN 1504-3 carry their own bond figures — R3 at least 1.5 N/mm2, R4 at least 2.0 N/mm2. Structural strengthening systems (bonded plate, carbon fibre wrap) are commonly specified in the 1.4-1.5 N/mm2 range with a concrete failure mode — ACI 440.2R gives 1.4 N/mm2 (200 psi) — but the designer and the system supplier set the acceptance figure for the job, and it is entered into the method statement before testing starts. | Pull-off testing with a hydraulic adhesion tester on 50 mm partially cored dollies, to EN 1542, ASTM C1583 or ASTM D7234 — record the failure mode as well as the load, since a 2.0 N/mm2 glue-line failure and a 1.4 N/mm2 concrete failure mean opposite things. Compressive strength screened by rebound hammer to IS 516 (Part 5/Sec 4) and ultrasonic pulse velocity to IS 516 (Part 5/Sec 1) — the methods formerly IS 13311 (Parts 2 and 1), both withdrawn — confirmed by extracted cores where readings are marginal or disputed. | If the applied system is stronger than the skin it is bonded to, the failure plane moves into the concrete and the floor or overlay eventually lifts carrying a 2-5 mm layer of the parent slab with it, turning a finishes defect into removal of sound structure. |
| Surface profile and preparation standard All bonded resin floors and overlays, repair mortars, protective coatings on steel and concrete, waterproofing membranes. | On concrete, profile is specified against the ICRI CSP scale (CSP 1-10, ICRI 310.2R): roughly CSP 1-3 for sealers and thin coats, CSP 3-5 for self-levelling and slurry systems to about 3 mm, CSP 5-9 for trowelled screeds and heavy-duty overlays — thicker system, coarser profile. On steel, the near-universal specification for high-performance systems is Sa 2.5 to ISO 8501-1, with St 2 / St 3 accepted for maintenance and touch-up. Blast profile is specified as an ISO 8503 comparator grade (fine / medium / coarse, stated separately for shot and for grit) TOGETHER WITH the micron band the paint maker requires for the film thickness being applied. Do not carry a single micron range from one project to the next — the grade boundaries differ between shot and grit, and the abrasive on site may not be able to produce it. | Concrete: ICRI CSP moulded comparator chips held against the prepared surface area by area, with agreed reference panels retained on site. Steel: ISO 8501-1 pictorial standards for cleanliness; ISO 8503 comparators or replica tape to ASTM D4417 for roughness. Preparation by mechanical means — captive-shot or grit blasting, diamond grinding, scabbling, hydro-demolition — not acid etching, unless the specification explicitly permits it. | A power-floated slab that has only been ground smooth offers no mechanical key, so a 6 mm screed relies on chemical adhesion alone and debonds under braking forklift wheels, sounding hollow across whole bays within a season. |
| Laitance, curing compound and surface contamination Every bonded system without exception. | Pass/fail, not a range: all laitance, curing compound, form release oil, grease, dust, algae, previous coatings and free salts removed to a sound, open-textured substrate. Where soluble salts are specified — steel, marine or industrial exposure — acceptance commonly falls in the range 20-50 mg/m2 chloride depending on exposure class, but this varies widely between specifications and the coating manufacturer’s limit governs. Where acid etching is permitted at all, surface pH must be returned to the specified band before priming. | Visual and tactile inspection plus a water-drop absorbency test — a bead standing proud indicates residual curing compound, sealer or oil; immediate darkening indicates an open surface. NAME THE SUBSTRATE AGAINST EACH METHOD: dust on steel to ISO 8502-3, with the same tape method applied to concrete only where the specification says so explicitly; soluble salts by Bresle patch sampling to ISO 8502-6 with conductometric determination to ISO 8502-9 (both written for steel); surface pH after cleaning or etching to ASTM D4262; concrete cleaning and abrading to ASTM D4258 and ASTM D4259. The ISO 8502 series is a steel-preparation series — applying it to concrete is done in practice, but by extension, and a clause that calls it up against a concrete floor without saying so is a point a contractor can argue. | Laitance is a 1-3 mm weak, dusty skin with almost no tensile strength, so the coating bonds perfectly to it and it lets go of the concrete, giving a pull-off result under 0.5 N/mm2 and rejection of a system that has already been paid for. |
| Ventilation, confined space and fire control Tank and pipe linings, basement and lift-pit tanking, sunken slabs and sumps, torch-applied and bituminous membrane work, any solvent-borne coating in an enclosed area. | Confined space entry permit, forced ventilation and continuous LEL and oxygen monitoring wherever solvent-containing material is applied in an enclosed or below-grade space. Ignition sources removed and flameproof lighting and equipment used. Hot work permit, fire watch and extinguishers for torch-applied membrane work, with the fire watch maintained for a stated period after work stops. PPE and respiratory protection per the SDS. No entry without a standby person and a means of rescue. | Permits issued and displayed at the working face; gas monitor calibrated and in date, readings logged; ventilation running and airflow confirmed before entry; extinguishers and water present and in date; fire watch named on the permit and physically present. | This is a stop-work condition in its own right and the one most often skipped. Solvent coatings in basements, lift pits, tanks, sumps and sunken slabs, and torch-applied membranes on terraces, are where people are hurt — its absence from a go/no-go table is a safety gap, not a technical one. |
| Services, penetrations and pressure test before waterproofing All wet-area, terrace, podium and basement waterproofing. | All pipes, sleeves, conduits, drains and outlets final-fixed, sleeved and grouted before waterproofing starts, with no drilling or fixing into the deck permitted afterwards. Plumbing and drainage pressure- and leak-tested and signed off before the membrane goes down. Coving and fillets formed to the specified radius at all upstands and internal angles. Termination heights, upstands, drip details and turn-ups set out and agreed. | Signed services clearance and pressure-test record read against the marked-up deck drawing, with the drawing retained; visual confirmation of coving and terminations before the first coat. | Waterproofing a sunken slab or toilet before the plumbing has been pressure-tested, or drilling a new conduit through a finished membrane, is the single commonest genuine cause of a stopped or repeated job on an Indian site. This is the row a supervisor points to in order to refuse to start. |
| Approved method statement and signed-off mock-up Every applied system on a project of any size. | Method statement approved before work starts, with the manufacturer’s written limits for moisture, temperature, dew point, recoat window and cure transcribed into it as project-specific figures rather than left as a datasheet reference. Trial area or mock-up of stated size laid in the actual site conditions with the actual crew and materials, tested (pull-off, wet and dry film thickness, finish, colour, slip resistance where specified) and signed off by the client or consultant. The approved trial area retained undisturbed as the reference standard for the works and for any later dispute. | Approved method statement on site, current revision, signed. Mock-up location recorded and protected; test results attached to the approval; photographic record at handover. | This is the mechanism by which every ‘the datasheet governs’ elsewhere in this table actually reaches the person on site. Without it there is no agreed acceptance standard, and the argument at handover has nothing to be settled against. |
| Concrete age before coating Epoxy and PU floors and coatings, liquid and sheet membranes, tank linings, bonded overlays. | The working convention is 28 days for new concrete before an impermeable coating or membrane, and that is what most tenders write; the honest position is that 28 days is a proxy, not the criterion. What has to be satisfied is moisture content, substrate strength and completion of the bulk of early shrinkage — a 200 mm raft in monsoon humidity may still fail the moisture test at 60 days, while a thin topping in dry April heat can be ready earlier. Cementitious waterproofing, polymer-modified mortars and moisture-tolerant primers can usually go on much earlier, often 3-7 days. For cementitious screeds a widely used rule of thumb is roughly 1 mm drying per day for the first 50 mm in good drying conditions, and considerably slower beyond. The moisture test overrides the calendar in both directions. | Concrete pour records and the cube results for the pour in question, read together with the moisture tests above — the age check is a documentation check, not an instrument reading. Where cubes are marginal or the pour record is missing, treat strength as unverified and test the surface directly by pull-off. | An impermeable coating laid on green concrete seals in residual water and high alkalinity. Water driven to the underside of the film blisters it osmotically, and the wet, high-pH interface degrades the bond. Ester-containing materials — alkyds, some polyesters and water-dispersed adhesives — are additionally attacked by alkaline hydrolysis (saponification), which leaves a soapy film at the bond line. Cured amine-cured epoxies are broadly alkali-resistant, so blistering rather than saponification is what fails them. |
| Mixing water and cementitious inputs SSD substrates, polymer-modified repair mortars, micro-concretes, cementitious waterproofing, screeds to falls, cementitious grouts. | Mixing and curing water to conform to IS 456 cl. 5.4 — potable water is generally acceptable; where the source is not potable it is tested against the IS 456 limits for solids, chlorides, sulphates and pH before use, and sea water is not used. Water per bag strictly as the datasheet, measured with a calibrated water measure at the mixing station, not judged by eye. No water added after mixing to restore workability. | Water test certificate for the source on file and re-checked if the source changes; water measure present at the mixing station and mix ratios posted at it. | Site water is routinely drawn from a borewell or tanker and can be brackish, silty or chloride-bearing — using it in a polymer-modified mortar placed against cleaned reinforcement is a stop-work condition. Over-watering to improve workability is the commonest site cause of low bond and shrinkage cracking in these products. |
| Crack width limits and treatment threshold Waterproofing membranes and coatings, protective and decorative coatings on concrete, resin floors, injection and structural repair works. | Two separate numbers, routinely confused on site. The design durability limit is IS 456 cl. 35.3.2: surface crack width generally not exceeding 0.3 mm, an upper limit of 0.2 mm where the member is exposed to weather, continuous moisture, soil or ground water, and 0.1 mm for particularly aggressive environments. The application decision rule is different and turns on whether the crack is dormant or live and on the crack-bridging class of the coating: fine dormant cracks below roughly 0.3 mm are bridged by an elastomeric system of suitable class (classified under EN 1504-2 by the EN 1062-7 method); dormant cracks from about 0.3 mm upward are routed out and filled before coating; live or moving cracks are not coated with a STATIC crack-bridging system at any width — they are converted into a sealed induced joint, injected with a flexible resin, or, where the measured movement is inside the amplitude the system was tested at, covered with a system classified for DYNAMIC crack bridging. Structural cracks go to the designer before any product decision. | Crack width comparator card or graduated crack microscope reading to 0.02 mm, taken at several points along each crack rather than at the worst point only. WHETHER A CRACK IS LIVE IS A SURVEY-STAGE ACTIVITY, NOT A PRE-APPLICATION ONE: monitoring is started at survey stage with tell-tale gauges, Demec studs or crack monitors read over a minimum of two to four weeks so a full diurnal and, where possible, seasonal cycle is captured. Where monitoring has not been carried out, the crack is treated as live until the designer rules otherwise, and coating over it does not start. Depth and extent by ultrasonic pulse velocity to IS 516 (Part 5/Sec 1) or by coring where it matters structurally. | A moving crack coated with a non-bridging system reappears through the new finish within one thermal cycle, splitting the membrane along its length and creating a water path that is now hidden beneath an intact-looking coating. |
| Joint width, depth and width-to-depth ratio Movement, expansion, construction and perimeter joints in floors, terraces, water-retaining structures, facades and glazing. | Joint width follows movement, not convenience: with a movement accommodation factor commonly around 25% for PU and polysulphide, the joint must be at least four times the calculated movement. Sealant depth follows ASTM C1193: for joints from about 6 mm to 12 mm wide, depth equal to the joint width with a minimum of 6 mm; for joints wider than 12 mm, depth equal to half the width, capped at about 12-13 mm regardless of width. A closed-cell backer rod or bond-breaker tape is mandatory so the sealant adheres on two faces only. Epoxy and semi-rigid fillers for saw-cut contraction joints in floors follow a different rule and are normally filled full depth. MAF, ratio and primer requirement are product properties and the datasheet governs. | Vernier or joint gauge for width and depth at intervals along the joint, with depth checked after the backer rod is set — the depth that matters is sealant depth, not joint depth. Backer rod diameter typically around 25% oversized to joint width so it stays compressed. ASTM C1193 sets out joint design and sealant use practice; two-part polysulphide sealants are specified in India under IS 12118. | A joint sealed too deep, or bonded to the joint base as well as the two faces, is over-constrained and cannot stretch, so it tears cohesively down the middle or peels off one face on the first cold night and leaks from that point on. |
| Wind and rain restrictions External coatings, liquid- and torch-applied membranes, terrace and facade work, spray-applied linings, external renders and cementitious overlays. | Rain: no application where rain is expected inside the product’s stated rain-resistance or early water-resistance time — commonly 1-2 h for some fast systems, 4-6 h for many water-based and cementitious products, up to 24 h for others. The spread is wide enough that no site rule of thumb is safe; read the figure off the datasheet and read the forecast, and in NCR monsoon conditions treat the afternoon build-up as the planning constraint. WIND: spray application is normally suspended above roughly 15-20 km/h because of overspray drift and dry spray. This is usually THE GOVERNING LIMIT and it sits well BELOW the wind speed at which access equipment is withdrawn — suspended cradles, MEWPs and scaffold working platforms are typically stopped at manufacturer-stated limits in the region of 40-45 km/h. A day that is safe for access can still be unfit for spraying. Take both limits from the equipment manufacturer and the coating datasheet, and record the lower of the two. | Handheld anemometer at the working face, not at ground level — the wind at a twelfth-floor facade is not the wind in the site office compound. Rain-resistance time from the datasheet, against the forecast and, on longer contracts, an on-site rain gauge and daily log. Overspray drift assessed by a trial spray and by screening or masking of adjacent property before work starts, not after a claim. | Rain inside the stated resistance window washes uncured binder off the surface, leaving a chalky, weak, patchy film with no adhesion that has to be stripped and reapplied at the applicator’s cost. |
| Curing period — substrate and applied system Concrete substrates before any bonded system; repair mortars and micro-concretes; cementitious waterproofing; resin floors and linings before traffic or water testing. | Two curing periods, and both are checked. SUBSTRATE: IS 456 cl. 13.5.1 requires moist curing for at least 7 days for ordinary Portland cement concrete and at least 10 days where mineral admixtures or blended cements are used; for concrete exposed to dry and hot weather the period shall not be less than 10 days, and for blended cements or mineral admixtures IS 456 RECOMMENDS that these minimum periods be extended to 14 days. Where 14 days is to be enforced, write it into the specification rather than relying on the code’s recommendation. Curing compounds are a special case — where a bonded coating, screed or membrane follows, either use no curing compound or use a removable grade and remove it mechanically, because a residual curing membrane is a bond breaker. APPLIED SYSTEM: resin floors typically take foot traffic at about 24 h, light traffic at 2-4 days and full chemical and mechanical cure at about 7 days at 20 degC, with cure time roughly doubling for each 10 degC fall in temperature. All product-specific; the datasheet governs. | Curing regime recorded against pour date on the concrete pour record and verified by observation of ponding, wet hessian, curing compound or membrane cover. For the applied system, elapsed time logged against measured substrate temperature, supported by a shore hardness reading or solvent rub check before the area is released. Water and flood testing on waterproofing is run only after the stated full cure, not after initial set. | Releasing an epoxy floor to forklift traffic at 48 h when full cure at that temperature is 7 days prints wheel tracks permanently into a soft film, and the bay can no longer be made good without recoating it. |
| Overcoat / recoat window Multi-coat epoxy, PU and MMA systems; primer / body coat / seal coat sequences; liquid membranes applied in two or more passes; steel protective coating systems. | Every multi-coat resin system carries both a minimum and a maximum recoat interval, and both are temperature-dependent. Indicative epoxy figures at 20 degC are a minimum of roughly 16-24 h and a maximum of roughly 48-72 h; at 35 degC the same product may run 6-8 h minimum and 24 h maximum. Applying inside the minimum puts the next coat onto a base coat that has not developed enough cure to carry it, giving softening, wrinkling and sinkage; in solvent-borne systems it additionally traps solvent. Passing the maximum leaves a fully cured, chemically unreceptive surface, and the next coat must then be mechanically abraded and solvent wiped before application. The recoat table on the current datasheet, read at the actual substrate temperature, governs — not the number remembered from the last project. | Time and substrate temperature of each coat logged on the application record and read against the datasheet recoat table. Wet film thickness checked with a comb gauge during application and dry film thickness confirmed to ISO 2808, or ISO 19840 on blast-cleaned steel, since an over-applied coat cures more slowly and shifts the window. Thumb-twist and solvent rub checks for cure state where the interval has been exceeded or is disputed. | Overcoating a glossy, fully cured epoxy two days past the maximum window gives interlayer delamination, and the topcoat lifts cleanly in sheets with a mirror-smooth back face, forcing a full strip and reapply over the whole area. |
| Substrate soundness — hollow and delaminated areas Bonded screeds and overlays, repair and rehabilitation works, waterproofing over existing decks, floor coatings on existing slabs, facade repair. | Pass/fail rather than a range: no hollow-sounding, drummy or delaminated area is left in place beneath a bonded system. Sounding covers 100% of the area to be treated, the boundary of each hollow zone is marked, broken out to sound concrete and reinstated with the specified repair mortar, which must then reach its own cure before the main system starts. On repair works break-out is taken beyond the visibly damaged area to where the substrate sounds solid — commonly 50-100 mm past the last drummy point, with square-cut edges of roughly 10-15 mm depth rather than feathered edges. The reinstatement material class and its own datasheet, with EN 1504-3, govern the repair. | Hammer tap, steel rod or chain drag survey over the full area; ASTM D4580 sets out the sounding practice. Marginal or extensive areas confirmed by ultrasonic pulse velocity to IS 516 (Part 5/Sec 1), impact-echo, or coring. The marked-up survey drawing should be agreed and signed before preparation starts, since it drives the repair quantity in the bill. | A hollow bay left under a new screed has no load path to the slab, so the screed spans the void and cracks along the boundary of the delamination under the first wheel load, taking the new finish with it. |
| Free water, active leakage and hydrostatic condition Basement and retaining wall tanking, lift pits, water-retaining structures and tank linings, podium and terrace waterproofing, injection grouting. | No standing water, no running water and no active leak at the point of application: free water is removed and any live leak stopped with a rapid-setting plugging compound and allowed to set before the membrane or coating goes on. Where the structure is subject to negative-side water pressure — basement rafts and retaining walls, lift pits, water tanks — either the system must be one rated for negative-side application, or the water table must be drawn down and held down by dewatering until the positive-side system has fully cured. For tanking and tank linings the applicable head, and whether it acts positive or negative, is a design input confirmed before product selection, not after. | Visual inspection of the whole area immediately before application, and again after any overnight rain or wash-down; seepage judged over a holding period rather than a single glance, since water re-emerges from cracks and construction joints after the surface looks dry. Dewatering records and standpipe or piezometer readings where a water table is being held down. Squeegee and forced-air drying followed by re-inspection. | Water under positive pressure behind a positive-side membrane pushes it off the substrate as it cures, and the blistered, tented membrane over the line of the construction joint appears only once the dewatering pumps are switched off and the job has been signed. |
| Falls, drainage and ponding Terrace, podium, balcony, sunken slab and wet-area waterproofing; car park decks; roof coatings and membranes; industrial floors with wash-down. | Falls are set before waterproofing, not corrected afterwards. Indian practice for terraces and exposed decks is a minimum fall towards outlets of about 1 in 100, with STEEPER falls — 1 in 80, or 1 in 60 — specified where the run is long, the finish is tiled, or the deck is otherwise prone to holding water. IS 3067 covers general design details and preparatory work, and the project specification or CPWD schedule governs the figure actually contracted. Anything FLATTER than 1 in 100 is a designer decision and is not accepted on site without written instruction. Outlets, khurras and rainwater pipes must be in place, at the low point and free. | Dumpy level, laser level, or spirit level and straight edge over the full run from high point to each outlet, recorded as a levels grid rather than as spot checks. Practical confirmation by flooding or hosing the deck and marking any area holding water after 20-30 minutes. Outlet inverts checked against finished screed level and drainage confirmed free before the deck is closed. | Water standing permanently on a membrane finds every pinhole and lap given enough time, and the leak below then appears nowhere near the defect, so the repair becomes a search across the whole terrace instead of a patch. |
| Reinforcement preparation and cover in repair areas Concrete repair and rehabilitation, spall repair, structural strengthening, marine and industrial refurbishment. | Where corroded reinforcement is exposed, concrete is broken out to give clear working space behind the bar — commonly 15-25 mm clearance where corrosion runs the full circumference, so the repair mortar can be compacted fully behind the steel; the exact figure follows aggregate size and the repair system, with EN 1504-10 and the mortar datasheet governing. Bars are cleaned to bright metal over the full circumference and for a stated length beyond visible corrosion, commonly around 50 mm — to St 3 by power tool where the bar is cleaned in situ, since Sa 2.5 is effectively unachievable on the back face of an embedded bar and should be specified only where the bar can be fully exposed and blast-cleaned. Section loss is measured and reported to the designer before reinstatement; supplementary bar is a design decision, not a site one. Where a zinc-rich or cementitious bar primer is specified its overcoat window is short, often measured in hours. Cover to the reinstated face is per design and the IS 456 exposure class. | Cover meter to locate bars and confirm cover, with bar positions marked before any saw-cutting; chipping and visual survey for the extent of corrosion; vernier or micrometer for residual bar diameter against nominal. Carbonation depth by phenolphthalein indicator on a freshly broken face, and chloride content by drilled dust sampling and titration where chloride-induced corrosion is suspected, since the two mechanisms call for different break-out extents and different repair principles. Half-cell potential survey to ASTM C876 to identify active areas beyond the visibly spalled zone. | Reinstating over a bar that is still contaminated, or filling from one side without clearance behind it, leaves a void and an active anode adjacent to fresh alkaline mortar, and the incipient-anode effect then drives new spalling in a ring immediately around the patch within a year or two. |
Working tools
Calculators, selectors and the catalogue
These already live on the site and are maintained there. This page points at them rather than keeping a second copy that would drift.
Quantity calculators
Waterproofing, flooring, grout and joint-sealant volumes from area and geometry.
OpenExpansion joint selector
Four answers — location, width, traffic, seismic — and it names the joint family.
OpenComparison tools
Brand against brand, system against system, on the axes that decide the choice.
OpenProduct catalogue
All 2,406 products, filterable by category, brand and whether the datasheet is on file.
OpenSelection guides
Ten discipline guides that take a site condition and work to the system.
OpenTechnical assistant
Published specifications, coverage arithmetic and product comparisons, answered from our own pages.
OpenSubmittals
The documentation that gets a system approved
Material approval fails on paperwork more often than on product. Everything below is issued against the specified system, not a generic pack.
Technical Data Sheet (TDS) On file
Current revision, per product, direct from the manufacturer’s published literature.
Safety Data Sheet (SDS) On file
Required for site HSE files and for material approval on most institutional projects.
Method statement
Sequence, surface preparation, ambient limits, application and curing, written against the specified system.
BOQ and specification support
Clause text, measurement basis and quantity take-off against your drawings.
Manufacturer test certificate
Batch-linked, for material acceptance where the specification calls for it.
Warranty documentation
Issued on applied work, scope and duration stated in writing before the order.
Working with Space Arc
What an authorised distributor and applicator actually changes
Four things that matter on a project that gets audited.
Authorised, not grey market
Every product is bought through the manufacturer’s authorised channel, so batch numbers trace back and warranties stand. On a project that gets audited, that is the difference between an approved submittal and a rejected one.
We supply and we apply
The same firm that specifies the system installs it. There is no gap between the specification and the workmanship for a problem to fall into, and no second party to point at when something fails.
Nine ranges, one recommendation
Carrying nine manufacturers means the recommendation can follow the condition rather than the stock. Where Fosroc fits we lead with it and say why; where it does not, we name the brand that does.
2,406 products, published specifications
Every product we supply has its published technical data on this site — coverage, mixing, strengths, standards. Nothing is quoted from memory, by us or by the assistant.
Send us the drawings
Specification support, quantity take-off, method statements and site attendance — from an engineer who will also be there when the material goes down.