Waterproofing and chemicals — price, types and what to check
Small cost, big protection against leaks and cracks.
Most leakage complaints in Indian homes come from roofs, bathrooms and external walls. Construction chemicals — waterproofing, admixtures, adhesives, grouts and anti-termite — stop them at the source.
The basics
- Integral waterproofing is mixed into concrete and plaster; coatings and membranes go on top.
- Tile adhesives and epoxy grouts have largely replaced cement mortar for tiling.
- Anti-termite treatment is done in the soil before the floor is cast.
Waterproofing and chemicals types and price ranges in India
| Type | Specification | Best used for | Indicative price |
|---|---|---|---|
| Integral waterproofing liquid | Mixed in | Concrete and plaster | ₹150–300 |
| Cementitious coating, 2-component | Polymer-modified | Bathrooms, sunken slabs, tanks | ₹150–250 |
| Elastomeric / PU roof coating | Liquid applied | Terraces and roofs | ₹250–550 |
| APP / SBS membrane | 3–4 mm | Terraces and basements | ₹45–90 |
| Tile adhesive | C1 / C2 / C2TE | Tile fixing | ₹15–40 |
| Epoxy grout | Stain-proof | Bathroom and kitchen joints | ₹450–1,000 |
| Plasticiser / superplasticiser | IS 9103 | Workable, stronger concrete | ₹60–150 |
| Anti-termite treatment | IS 6313 | Pre-construction soil treatment | ₹8–15 |
Quality checks before you accept delivery
- Check batch and expiry dates; mix 2-component packs completely.
- Buy sealed original packs — fakes circulate in local markets.
- Ask applicators for a written warranty.
- Match product code and batch on the pack with the invoice.
- Work out the quantity from the coverage rate printed on the pack.
- Ask for test certificates for membranes.
Pro tips
- Do anti-termite treatment at plinth stage, before PCC — it's nearly impossible later.
- Bathrooms: coat the floor and 300 mm up the walls (1.8 m in the shower), then pond-test 48 hours before tiling.
- Terraces need a 1:100 slope to outlets and a rounded cove at the parapet joint before coating.
- Use a crystalline waterproofing admixture in sump and basement concrete.
- Recoat terrace waterproofing every 5–7 years.
- Apply coatings in two coats at right angles to each other.
- Protect waterproofing with screed or tiles before other trades walk on it.
Mistakes to avoid
- Tiling bathrooms without waterproofing.
- Coating damp surfaces.
- Leaving pipe penetrations unsealed.
- Thinning coatings beyond the maker's ratio.
- Stopping at a single coat.
Where you can save
- Waterproofing during construction costs a fraction of later leak repairs.
- Buy the primer and coating from one brand to keep the warranty valid.
How much you need
Budget about 1–2% of construction cost for waterproofing.
Brands to know
Dr. Fixit, Fosroc, Sika, MYK Laticrete, Roff, Master Builders, Ardex Endura
Related materials
False ceiling and POPGypsum, POP, PVC and grid ceilings.Paints and puttyPutty, primer, emulsion — and the final colours.Ready-mix plaster and gypsumCement, ready-mix and gypsum plaster, mesh and bonding agents.Wall panels and wallpaperFluted panels, WPC louvers, PVC boards, wallpaper, acoustics.Insulation and heat reductionXPS, PUF, glass wool, rock wool and reflective barriers.