Fosroc Supercast PVC
Extruded high-grade PVC waterstops for sealing movement and construction joints in cast in-situ concrete water-retaining and water-excluding structures.
What is it?
A range of extruded high-grade PVC waterstop profiles (Hydrofoil, Watafoil, XHD and Rearguard) cast into concrete joints to form a continuous, flexible water-tight barrier.
Where is it used?
Construction, contraction and expansion joints in reservoirs, sewage tanks, basements, tunnels, podiums and retaining walls across India.
Why use it?
Provides a permanent integral seal against water pressure (up to 10 bar) that flexes with structural movement of up to 10 mm without leaking.
How is it applied?
Positioned centrally within or externally against the joint, wired or nailed to formwork/reinforcement, cast into the concrete, and heat-welded at site joints and intersections.
About Fosroc Supercast PVC
Fosroc Supercast PVC is the company’s established range of polyvinyl-chloride waterstops engineered to provide an integral sealing system for movement and construction joints in concrete cast in-situ. Rather than a single item, “Supercast PVC” is a family of extruded profiles formulated from a high-grade plasticised PVC compound chosen for its long-term flexibility and durability inside the concrete pour. The compound is formulated to meet the US Corps of Engineers specification CRD-C 572, the benchmark standard for PVC waterstops worldwide, and the material carries Water Byelaws / WRc approval for use in contact with potable water (listing number 8804054), which makes it acceptable for drinking-water reservoirs and treatment tanks.
The range divides into centrally placed profiles, which sit within the thickness of the concrete and resist water pressure from either face, and externally placed profiles, which are fixed to the outer surface of the slab or wall. Centrally placed types include Supercast Hydrofoil and Watafoil, plus the heavier XHD Hydrofoil and XHD Watafoil for deep, high-head pours. Externally placed types include Rearguard S, Rearguard R, Rearguard Kicker and Angleguard, each shaped for a specific joint condition such as kicker joints, soffit level changes or blinding-supported floor slabs. Every profile uses a fully continuous four-bulb design that combines two sealing mechanisms: the valve principle, where edge bulbs anchor into adjacent panels and tension the membrane to seal as a joint opens, and the tortuous-path principle, where the ribbed cross-section lengthens and complicates any potential seepage route. Centrally placed sections carry eyeletted, reinforced edge flanges so they can be wired securely to surrounding reinforcement, while Rearguard sections have a nailing flange for fixing to vertical shutters. For Space Arc Engineering’s clients in Delhi NCR and across India, Supercast PVC is the go-to specification for water-retaining and below-grade waterproofing where a cast-in mechanical seal is required at the joint.
The technical insight
The performance of Supercast PVC rests on the plasticised PVC compound meeting CRD-C 572, which dictates a minimum tensile strength of 14 N/mm2 (tested to BS 2782 at 25 degrees C) and a minimum elongation at break of 300 percent, with hardness in the Shore A 80 to 90 band. These figures matter on site because the waterstop must stretch and recover as a joint opens under drying shrinkage, thermal cycling or settlement, then clamp back without splitting. The published joint movement capacity is up to 10 mm and the hydrostatic head rating is up to 100 m, equivalent to 10 bar of water pressure. Profile width is selected against wall thickness: the 250 mm width suits walls of 250 mm and over, while 150 mm and 200 mm widths are used for thinner sections, and the 330 mm Hydrofoil is reserved for roof slabs where greater movement is expected. The single most critical site detail is the heat-welded joint: ends are cut square, aligned in a jig, melted against a heated blade until a continuous bead of PVC forms, then fused. A poorly welded butt joint or an unwelded overlap is the most common cause of waterstop failure, so factory-moulded intersection pieces are specified for all wall-to-floor transitions to keep the four-bulb profile continuous.
Where it is used
- Construction and contraction joints in RCC water-retaining structures (reservoirs, water towers, sewage and effluent tanks)
- Expansion joints in dams, culverts, canals, spillways and swimming pools
- Below-grade waterproofing of basements, underground car parks and lift pits
- Tunnels, subways, cut-and-cover structures and metro works
- Retaining walls, abutments, roof decks and podium slabs
- Bunded / containment areas surrounding liquid-retaining tanks
- Wall-to-kicker and wall-to-floor slab joints using Rearguard Kicker and moulded transition pieces
Key advantages
- Wide profile range (Hydrofoil, Watafoil, XHD, Rearguard S/R, Kicker, Angleguard) to suit virtually every joint condition
- Fully continuous four-bulb design combining valve and tortuous-path sealing principles
- Meets US Corps of Engineers CRD-C 572 with 14 N/mm2 tensile and 300% elongation
- WRc / Water Byelaws approved for contact with potable water
- Reinforced, eyeletted edge flanges (central profiles) and nailing flanges (Rearguard) for positive, secure fixing
- Resists water pressure from either face when centrally placed, suiting water-retaining tanks
- Simple on-site heat-welding plus factory-moulded intersection pieces maintain joint continuity
- High elongation and Shore A 80-90 flexibility accommodate up to 10 mm of joint movement
Limitations & considerations
- Must be cast into fresh concrete; it cannot be retrofitted into an existing hardened joint
- Performance is entirely dependent on correct positioning and full concrete compaction around the profile, with no voids
- Externally placed Rearguard profiles in walls resist water pressure only from the face to which they are fixed
- Requires Fosroc heat-welding equipment and trained operators; cold overlaps and bad welds are a frequent failure point
- PVC is unsuitable for joints exposed to certain hydrocarbons, solvents or aggressive chemicals, where thermoplastic compatibility must be checked
- Not a substitute for surface waterproofing membranes, hydrophilic strips or crack-injection where those are the correct solution
- Dimensions are nominal and subject to manufacturing tolerances, so shop drawings should allow for fit-up
Selection & best practice
Select the profile by joint type and the width by wall thickness (250 mm width for walls 250 mm and over). Position centrally placed waterstops on the joint centreline and wire the eyeletted flanges to reinforcement, keeping brass eyelets outside the edge bulbs so they do not create water paths; fix Rearguard profiles by nailing through the outer flange with heads left proud. Ensure adequate clearance from rebar so concrete fully compacts around every bulb with no voids. Make all straight joints by heat-welding square-cut ends in the jig until a continuous molten bead forms, and use factory-moulded intersection and transition pieces for every change of direction and wall-to-floor connection rather than fabricating on site. Protect the exposed half of the waterstop from debris and damage between the first and second pours.
Specifications
| Material | Extruded high-grade plasticised PVC compound |
| Compound standard | US Corps of Engineers CRD-C 572 |
| Form | Extruded thermoplastic sections |
| Colour | Blue |
| Tensile strength | Minimum 14 N/mm2 (to BS 2782 at 25 deg C) |
| Elongation at break | Minimum 300% |
| Hardness | Shore A 80 to 90 |
| Hydrostatic head | Up to 100 m (10 bar) |
| Joint movement | Up to 10 mm |
| Centrally placed profiles | Hydrofoil, Watafoil, XHD Hydrofoil, XHD Watafoil |
| Externally placed profiles | Rearguard S, Rearguard R, Rearguard Kicker, Angleguard |
| Available widths | 150, 200, 250 and 330 mm |
| Roll length | 10 to 20 m (profile dependent); Angleguard in 3 m lengths |
| Potable water approval | WRc / Water Byelaws Scheme approved (listing 8804054) |
| Site jointing | Fusion heat-welding using Fosroc PVC welding equipment |
Industry use cases
Water & wastewater infrastructure
Sealing construction and expansion joints in RCC reservoirs, overhead and underground tanks, STPs and ETPs where centrally placed Hydrofoil resists head from either face and WRc approval permits potable-water contact.
Metro, rail & tunnelling
Cut-and-cover boxes, station diaphragm walls and subway joints where high-head XHD Hydrofoil profiles handle deep pours and sustained groundwater pressure.
Commercial & residential basements
Below-grade car parks, lift pits and basement rafts using Rearguard externally on the blinding and wall-to-floor moulded transitions to keep the four-bulb seal continuous.
Dams, canals & hydraulic works
Movement joints in spillways, culverts and canal linings where up to 10 mm of joint movement must be accommodated without loss of water-tightness.
Industrial containment
Bunded areas and chemical-tank plinths around liquid-retaining structures, subject to checking PVC compatibility with the contained medium.
Frequently asked questions
Is Fosroc Supercast PVC a single product or a range?
What water pressure can it withstand?
Is it safe for drinking-water tanks?
What is the difference between centrally placed and externally placed waterstops?
How are Supercast waterstops jointed on site?
Which width should I specify?
How we position Fosroc Supercast PVC
Within the Fosroc Supercast waterstop family, the PVC range is the workhorse cast-in seal for general water-retaining and below-grade joints. For joints needing more than mechanical sealing, Fosroc offers complementary systems: Supercast SW (a swellable hydrophilic strip) for simple construction joints, and Supercast Twinstop where a hydrophilic profile is combined for added security. Against competitors, Supercast PVC sits alongside Sika Waterbars (Sika India), Supercast-equivalent PVC waterstops from STP Limited and Dr. Fixit / Pidilite’s waterstop offerings, and MYK / MBS-type systems; the differentiators are the breadth of CRD-C 572-compliant profiles, WRc potable-water approval and Fosroc’s moulded intersection pieces. As an authorised Fosroc distributor for Delhi NCR and Pan-India, Space Arc Engineering supplies the full Supercast PVC profile range with technical selection support, and can cross-recommend hydrophilic or membrane systems where a PVC waterstop alone is not the optimal solution.
Related Waterproofing products
Source Fosroc Supercast PVC for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.