About UltraTech Seal & Dry ILW+

UltraTech Seal & Dry ILW+ belongs to a category Indian site engineers know well: the integral, or “admixture-type”, waterproofer. Instead of being troweled, sprayed or rolled onto a finished surface, it goes into the mix itself, added to the gauging water before the mortar or concrete is batched. That single distinction changes how you think about waterproofing failure. A membrane or coating fails when it is punctured, lapped badly, or simply wears through after years of monsoons and foot traffic. An integral admixture like ILW+ works from inside the matrix, reducing the capillary pathways water would otherwise travel through, so there is no separate layer to breach in the first place.

On site, the product is straightforward: measure 200 to 300 ml of ILW+ per 50 kg bag of cement, add it to the gauging water, and mix for 2-3 minutes before the mortar or concrete is prepared as normal. There is no primer, no separate topcoat, and no dedicated curing period beyond what the concrete or plaster itself needs, which is one reason contractors reach for it on basement rafts, external plaster and RCC roof slabs where sequencing a membrane installation would eat into the programme. UltraTech states the formulation meets IS 2645:2003, the Indian Standard for integral waterproofing compounds for cement mortar and concrete, and IS 9103:2000 for concrete admixtures, which gives specifiers a standards reference to write into a BOQ rather than relying on a brand name alone.

Where this fits on a typical Delhi NCR project: plaster in wet-area walls such as kitchens, toilets and external facades, masonry mortar in below-grade brickwork, RCC basement and podium slabs, screeds ahead of tiling, and industrial floor toppings where a coating would be too thin to survive trolley traffic. It is worth being clear about what it does not do. It is not a substitute for a membrane at a construction joint, an expansion joint, or a habitually ponding terrace; those still need a dedicated waterproofing system such as a torch-applied membrane, a PU coating or a crystalline slurry at the joint, in addition to, not instead of, an integral admixture in the concrete. Treat ILW+ as the first line of defence built into the structure, with membrane or coating systems layered on at the genuine weak points, meaning joints, upstands and pipe penetrations, rather than as a stand-alone waterproofing strategy for a habitable wet area.

Pack-size selection is worth planning rather than defaulting to whatever is on the shelf. A 1-litre pack covers a small repair batch or a single room’s plaster; the 5-litre and 20-litre packs are sized for slab pours and larger plaster runs, where working out total cement quantity in advance avoids a mid-pour scramble for another bottle. Site engineers ordering through Space Arc typically size the pack against the day’s planned cement consumption rather than the total project quantity, since opened containers are best used within a working season rather than left half-full in site storage.

The technical insight

The dosage band matters more than it looks. At the lower end, around 200 ml per 50 kg of cement, ILW+ behaves like a standard integral admixture, giving a useful water-tightness gain without much change to workability. Push toward 300 ml per 50 kg and you are typically compensating for richer mixes or a higher water-cement ratio, where the extra additive helps offset the permeability that a wetter mix would otherwise introduce. Site teams should trial the dosage against their actual site water-cement ratio rather than defaulting to the maximum on every pour, since over-dosing an integral admixture does not scale water-tightness linearly and can affect setting behaviour in some cement combinations. Because the product is added at the mixer rather than troweled on afterward, quality control shifts from inspecting a finished coat to verifying batching discipline: dosage measured by volume against the actual bag count, not eyeballed, and mixing time held to the full 2-3 minutes so the admixture disperses evenly through the gauging water before it meets the cement. On larger pours, it is worth keeping a batch record of dosage against cement consumed, since that record is the only real evidence of consistent application once the concrete has been placed and covered.

Where it is used

• RCC roof slabs and podium decks
• Basement raft foundations and retaining walls
• External and internal wall plaster in wet-prone areas
• Masonry mortar in below-grade and plinth brickwork
• Bonded screeds ahead of tiling or flooring
• Industrial floor toppings and utility-area concrete

Key advantages

• Mixed into the gauging water, so there is no separate coating step, primer or dedicated curing wait to sequence into the programme
• Reduces capillary water movement from within the concrete or mortar matrix, rather than relying on a surface layer that can be punctured or worn through
• Formulated to meet IS 2645:2003 for integral waterproofing compounds and IS 9103:2000 for concrete admixtures, giving specifiers a standards reference for the BOQ
• Dosage range of 200-300 ml per 50 kg of cement lets site teams tune the addition rate to the mix design rather than using one fixed rate everywhere
• 24-month shelf life in sealed, dry, cool storage suits sites that stock material ahead of a phased pour schedule

Limitations & considerations

• Not a substitute for membrane or coating systems at construction joints, expansion joints or genuinely ponding terraces, which still need dedicated joint treatment regardless of admixture use
• Manufacturer literature does not publish detailed composition data, so specifiers relying on chemistry-specific approvals should request the full TDS and MSDS directly
• Performance depends on batching discipline; inconsistent dosage or mixing time shows up later as inconsistent water-tightness, with no way to inspect or rework it after the pour
• Being an admixture rather than a membrane, it adds no waterproofing value to concrete that has already been cast; it has to be planned into the fresh mix design from the start

Selection & best practice

Specifications

Industry use cases

How we position UltraTech Seal & Dry ILW+

UltraTech Seal & Dry ILW+ sits in the same integral-admixture category as Fosroc’s Conplast WL range: both are gauging-water additives rather than surface coatings, both target IS 2645:2003 compliance, and the choice between them usually comes down to what is already standardised on a project’s approved-materials list, or an existing cement supply relationship, rather than any meaningful performance gap between the two.

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