About Dr. Fixit Pidiproof LW+ Super

{“name”:”Dr. Fixit Pidiproof LW+ Super”,”slug”:”drfixit-dr-fixit-pidiproof-lw-super”,”brand”:”Dr. Fixit”,”realProduct”:”yes”,”officialSource”:”https://www.drfixit.co.in/resources/library/technical-data/home-owners/dr-fixit-lw-super”,”category”:”admixtures”,”metaTitle”:”Dr. Fixit LW+ Super | Waterproofing Admixture | Space Arc”,”metaDescription”:”Dr. Fixit LW+ Super is Pidilite’s integral liquid admixture that waterproofs concrete and plaster, cuts shrinkage cracks, and delays steel corrosion.”,”heroSubtitle”:”The polymer-modified liquid admixture that goes into your concrete and plaster mix — waterproofing from within, cutting shrinkage cracks, and slowing corrosion before it starts.”,”glance”:{“whatIsIt”:”A pink liquid integral waterproofing admixture — a blend of surface-active plasticising agents and polymers — that gets dosed straight into the gauging water of site-mixed concrete, mortar and plaster.”,”whereUsed”:”RCC roof slabs, basements, water tanks and sumps, internal and external plastering, and general site-mixed concrete and mortar — especially batches using M-Sand.”,”whyUse”:”It densifies the concrete/mortar matrix to cut water permeability, reduces shrinkage cracking, keeps M-Sand mixes workable, and slows corrosion of embedded rebar by keeping the cover concrete tighter.”,”howApplied”:”Dosed at 200 ml per 50 kg bag of cement into the remaining 20-25% of mixing water — never onto dry cement — then mixed for roughly two minutes before placing or plastering.”},”about”:”Dr. Fixit LW+ Super (marketed on some Pidilite pages as Pidiproof LW+ Super) sits in the integral-admixture end of the Dr. Fixit waterproofing range, distinct from the surface-applied coatings the brand is best known for at the retail level. Instead of being brushed on after the concrete or plaster is cured, it goes into the mix itself — a liquid combination of surface-active plasticising agents and polymer additives that Pidilite formulated specifically to also work with M-Sand, which has become the default fine aggregate across most of Delhi NCR now that natural river sand supply is tightly regulated. The idea is simple: instead of fighting capillary water movement after the fact with a membrane, you make the concrete and mortar inherently less permeable while you’re pouring it.\n\nFor Space Arc’s site customers, that translates into a very specific role — it’s the admixture that goes into the roof slab concrete, the basement pour, or the external plaster batch, usually as the first layer of a waterproofing strategy that’s then finished with a topcoat system like Dr. Fixit Roofseal for full roof protection. It isn’t sold as a stand-alone waterproofing guarantee, and we don’t position it that way to clients — it’s the foundation layer, not the whole system. Where it earns its keep on a typical NCR site is workability: M-Sand mixes tend to go stiff and hard to finish faster than river-sand mixes, and LW+ Super’s plasticising action buys the mason real working time without pushing the water-cement ratio up, which is exactly the kind of trade-off that causes shrinkage cracking if it’s mismanaged manually.”,”technicalInsight”:”The chemistry does two jobs at once. The plasticising component disperses cement particles more evenly and lets the mix retain workability at a lower water-cement ratio than an unmodified batch would need — which is precisely why it holds up with M-Sand, whose higher fines content and angular particle shape otherwise stiffen a mix faster than rounded river sand. The polymer component then works alongside that lower w/c ratio to tighten the pore structure of the hardened concrete or mortar, which is what drives the IS 2645:2003 water-permeability pass and the reduced bleeding that shows up as fewer shrinkage cracks on cure. Because both effects are dosage-sensitive — the specification is built around 200 ml per 50 kg bag — overdosing doesn’t waterproof better, it just retards setting time and can pull compressive strength outside the IS 2645 limits, which is the single most common site mistake we see with integral admixtures generally, not just this one.”,”applications”:[“RCC roof slabs and terraces, as the base layer before a topcoat waterproofing system”,”Basement and retaining-wall concrete below the damp-proof course”,”Water tanks, sumps and other water-retaining RCC structures”,”Internal and external wall plastering, particularly with M-Sand mortars”,”Bathroom and toilet sunken slabs before screeding”,”General site-mixed concrete for foundations and plinth work”,”Repair and patch mortars where reduced permeability matters”,”Boundary and compound walls exposed to monsoon wetting”],”advantages”:[“Reduces water permeability of concrete and mortar to IS 2645:2003″,”Purpose-formulated to retain workability in M-Sand mixes, not just river-sand ones”,”Cuts shrinkage-crack development during and after curing”,”Delays corrosion onset by densifying the cover concrete around rebar”,”Fully liquid and easily dispersible — no premixing or special equipment needed”,”Keeps setting time and compressive strength within IS 2645 limits when dosed correctly”,”Priced and packed (1 to 50 litre) for everything from a bathroom slab to a full villa roof”,”Backed by a real IS-standard test regime rather than only marketing claims”],”limitations”:[“It’s an integral admixture, not a membrane — on exposed roof decks it’s typically paired with a Dr. Fixit topcoat system for a full waterproofing warranty, not relied on alone”,”Overdosing beyond 200 ml/50 kg retards setting and can pull compressive strength below spec, so site batching discipline matters”,”Must be added to the mixing water, never poured onto dry cement — that’s an easy step to get wrong with untrained labour”,”It’s a new-construction admixture, not a crack-repair or injection product for structures already showing leakage”,”Benefits depend on proper curing; skipping curing negates most of the permeability gain”,”No coverage figure is published for it, since dosage is by cement weight rather than area — estimating costs needs the mix design, not a coverage chart”],”bestPractice”:”Batch by cement weight, not by feel: 200 ml per 50 kg bag, added into the last 20-25% of mixing water after the dry cement, aggregate and bulk water have already been mixed for two to three minutes — never onto dry cement directly. Keep the water-cement ratio as low as the mix design allows, since that’s where LW+ Super’s plasticising action is actually earning its waterproofing benefit. Cure the finished slab or plaster properly for the full recommended period; skipping this undoes a large part of what the admixture is designed to do. And on any roof or terrace, plan for a compatible topcoat system on top rather than treating the admixture as the complete waterproofing solution.”,”specs”:[{“property”:”Appearance”,”value”:”Pink liquid”},{“property”:”Specific gravity @ 25°C”,”value”:”1.04 – 1.09″},{“property”:”Non-volatile content”,”value”:”15 – 16.5%”},{“property”:”pH value @ 30°C”,”value”:”13″},{“property”:”Chloride content”,”value”:”Max 2.00% (IS 2645:2003)”},{“property”:”Water permeability”,”value”:”Passes (IS 2645:2003)”},{“property”:”Compressive strength”,”value”:”Within IS 2645:2003 specification limits”},{“property”:”Dosage”,”value”:”200 ml per 50 kg bag of cement”},{“property”:”Pack sizes”,”value”:”1, 5, 10, 20 & 50 litre”},{“property”:”Shelf life”,”value”:”24 months from manufacture, stored cool and dry, unopened”}],”useCases”:[{“sector”:”Residential villa construction, Gurugram”,”detail”:”Dosed into the RCC roof slab concrete ahead of plastering and a Dr. Fixit topcoat system, to reduce shrinkage cracking before the finish waterproofing goes on.”},{“sector”:”Apartment block plastering, Delhi NCR”,”detail”:”Added to external wall plaster mortar made with M-Sand, where contractors need the extra open time LW+ Super gives to finish large wall runs without the mix stiffening early.”},{“sector”:”Basement RCC, South Delhi bungalow”,”detail”:”Used in below-DPC basement concrete where ground moisture and a shallow water table make an integral admixture a sensible first line of defence alongside external damp-proofing.”},{“sector”:”Underground sump / water tank, Noida industrial shed”,”detail”:”Specified in the tank walls and base slab concrete to reduce permeability in a structure that will be permanently in contact with stored water.”},{“sector”:”Toilet sunken slab renovation, Gurugram apartment”,”detail”:”Mixed into the screed concrete of a re-done sunken slab, a classic leak point in older NCR flats, before tiling and waterproofing membrane work.”}],”faq”:[{“q”:”Is Dr. Fixit LW+ Super a waterproof coating I paint on, or something I mix in?”,”a”:”It’s mixed in — it’s an integral admixture dosed into the gauging water of site-mixed concrete, mortar or plaster, not a coating you apply afterward.”},{“q”:”Can I use LW+ Super as my only waterproofing on an exposed roof?”,”a”:”You can, but we don’t recommend it alone for a roof deck. It’s normally the first layer, paired with a topcoat waterproofing system so you get a full system warranty rather than relying on the admixture by itself.”},{“q”:”What’s the right dosage, and will adding more waterproof better?”,”a”:”200 ml per 50 kg bag of cement. Adding more doesn’t improve waterproofing — it just retards setting time and risks pulling compressive strength outside the IS 2645 spec, so stick to the dosage.”},{“q”:”Does it actually work with M-Sand, or is that just marketing?”,”a”:”It’s genuinely formulated for M-Sand mixes — the plasticising component is what keeps M-Sand concrete and plaster workable for longer, since M-Sand stiffens faster than river sand on its own.”},{“q”:”Will it slow down or weaken my concrete?”,”a”:”Not at the correct dosage. Setting time and compressive strength stay within IS 2645:2003 limits when it’s batched properly; the risks only show up with overdosing or adding it to dry cement instead of water.”},{“q”:”How long can I store it, and does it need special handling?”,”a”:”24 months from the date of manufacture, kept cool, dry and unopened. Use rubber gloves and safety goggles when handling it, and rinse skin contact with plenty of water.”}],”positioning”:”Within the Dr. Fixit range, LW+ Super sits alongside — and is often specified together with — the brand’s roof topcoat systems like Dr. Fixit Roofseal and its plaster/repair mortar admixtures such as Pidiproof LW+; the admixture handles the concrete and plaster matrix, the topcoat handles the exposed surface. For specifiers who’ve standardised on Fosroc rather than Pidilite, or who are working strictly to IS 2645 with a lignosulphonate-based chemistry, Space Arc also supplies Fosroc Conplast WL as a direct integral-admixture equivalent, dosed at a comparable 125-200 ml per 50 kg of cement. Both are credible choices for the same job — the decision usually comes down to which brand’s system the rest of the project is already built around.”

The technical insight

The chemistry does two jobs at once. The plasticising component disperses cement particles more evenly and lets the mix retain workability at a lower water-cement ratio than an unmodified batch would need — which is precisely why it holds up with M-Sand, whose higher fines content and angular particle shape otherwise stiffen a mix faster than rounded river sand. The polymer component then works alongside that lower w/c ratio to tighten the pore structure of the hardened concrete or mortar, which is what drives the IS 2645:2003 water-permeability pass and the reduced bleeding that shows up as fewer shrinkage cracks on cure. Because both effects are dosage-sensitive — the specification is built around 200 ml per 50 kg bag — overdosing doesn’t waterproof better, it just retards setting time and can pull compressive strength outside the IS 2645 limits, which is the single most common site mistake we see with integral admixtures generally, not just this one.

Where it is used

• RCC roof slabs and terraces, as the base layer before a topcoat waterproofing system
• Basement and retaining-wall concrete below the damp-proof course
• Water tanks, sumps and other water-retaining RCC structures
• Internal and external wall plastering, particularly with M-Sand mortars
• Bathroom and toilet sunken slabs before screeding
• General site-mixed concrete for foundations and plinth work
• Repair and patch mortars where reduced permeability matters
• Boundary and compound walls exposed to monsoon wetting

Key advantages

• Reduces water permeability of concrete and mortar to IS 2645:2003
• Purpose-formulated to retain workability in M-Sand mixes, not just river-sand ones
• Cuts shrinkage-crack development during and after curing
• Delays corrosion onset by densifying the cover concrete around rebar
• Fully liquid and easily dispersible — no premixing or special equipment needed
• Keeps setting time and compressive strength within IS 2645 limits when dosed correctly
• Priced and packed (1 to 50 litre) for everything from a bathroom slab to a full villa roof
• Backed by a real IS-standard test regime rather than only marketing claims

Limitations & considerations

• It’s an integral admixture, not a membrane — on exposed roof decks it’s typically paired with a Dr. Fixit topcoat system for a full waterproofing warranty, not relied on alone
• Overdosing beyond 200 ml/50 kg retards setting and can pull compressive strength below spec, so site batching discipline matters
• Must be added to the mixing water, never poured onto dry cement — that’s an easy step to get wrong with untrained labour
• It’s a new-construction admixture, not a crack-repair or injection product for structures already showing leakage
• Benefits depend on proper curing; skipping curing negates most of the permeability gain
• No coverage figure is published for it, since dosage is by cement weight rather than area — estimating costs needs the mix design, not a coverage chart

Selection & best practice

Specifications

Industry use cases

How we position Dr. Fixit Pidiproof LW+ Super

Within the Dr. Fixit range, LW+ Super sits alongside — and is often specified together with — the brand’s roof topcoat systems like Dr. Fixit Roofseal and its plaster/repair mortar admixtures such as Pidiproof LW+; the admixture handles the concrete and plaster matrix, the topcoat handles the exposed surface. For specifiers who’ve standardised on Fosroc rather than Pidilite, or who are working strictly to IS 2645 with a lignosulphonate-based chemistry, Space Arc also supplies Fosroc Conplast WL as a direct integral-admixture equivalent, dosed at a comparable 125-200 ml per 50 kg of cement. Both are credible choices for the same job — the decision usually comes down to which brand’s system the rest of the project is already built around.

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