Specialist Waterproofing Subcontractor for Main Contractors
As a specialist subcontractor we take the waterproofing package off a main contractor's critical path. That means mobilising to your programme, holding your inspection points, coordinating with the trades either side of us, and producing the records your client's PMC will demand.
A project manager, planning engineer or procurement lead at a main contracting firm packaging out waterproofing.
What actually makes this difficult
The technical work overlaps with every other kind of building. The constraints are what differ, and they are what a contractor either understands or does not.
- Programme dependency
- Waterproofing sits between structure and finishes. Slippage propagates in both directions.
- Interface coordination
- MEP penetrations and RCC tolerances decide whether the barrier can actually be completed.
- Back-to-back liability
- Your obligations to the client flow down to us and have to be met.
- Measurement and billing
- Work must be measurable and billable against the package.
How we work on these projects
- Mobilise to your programme and confirm hold points in writing.
- Flag interface problems — uncollared MEP penetrations, out-of-tolerance falls — early, in writing.
- Photographic records at every stage, formatted for your handover file.
- Measurement and billing aligned to your package structure.
Systems this kind of project usually needs
- Basement Waterproofing
Basement waterproofing protects a below-grade structure against groundwater under hydrostatic pressure. Because the water pushes inward continuously, the reliable approach is a box-type system — a continuous barrier wrapping raft and retaining walls — applied pre-construction where possible.
- Podium Waterproofing
Podium waterproofing protects a landscaped or trafficked deck sitting above occupied space — typically parking, a clubhouse or retail. It is demanding because the barrier must survive planter soil, vehicle loads and heavy detailing around drains and columns, while any failure shows up as a leak into the space below, where it is expensive to trace..
- HDPE Membrane Waterproofing
HDPE membrane waterproofing uses a high-density polyethylene sheet, generally pre-applied below rafts and against retaining walls before concrete is poured. The key property is that fresh concrete bonds mechanically to the membrane's coated face, so water cannot track laterally between barrier and structure — the failure mode that defeats most loose-laid below-grade systems..
- Bathroom Waterproofing
Bathroom waterproofing seals the sunk slab and wet-area walls so water from daily use cannot reach the flat below. It is applied to the sunken portion before filling, carried up the walls as a skirting, and dressed carefully around every pipe penetration.
- Terrace Waterproofing
Terrace waterproofing is the application of a continuous water barrier across a roof slab, laid to a fall so rainwater drains rather than ponds. In Mumbai the usual choices are brick bat coba with china mosaic, an APP or SBS torch-on membrane, or a liquid-applied polyurethane or polyurea coating.
- Expansion Joint Treatment
Expansion joint treatment seals the deliberate gaps that let a structure move, using systems that accommodate that movement rather than resist it. Because the joint is designed to open and close, only a flexible sealing system with the right movement capability will survive — rigid filling of an expansion joint always fails..
- Box Type Waterproofing
Box type waterproofing wraps a below-grade structure in a fully continuous barrier — under the raft, up every retaining wall, and sealed at the top — so the structure sits inside an unbroken tank. It is the correct answer where groundwater exerts permanent hydrostatic pressure, because there is no joint or edge for water to find..
Main Contractors — questions we get asked
Can you mobilise at short notice for a pre-pour window?
Where the window is confirmed with reasonable notice, yes. Pre-applied below-grade membrane has one opportunity, so we confirm the hold point formally rather than relying on a verbal date.
Who is liable if another trade damages the membrane?
We photograph the completed membrane at handover to the next trade, which establishes its condition. Damage after that point is recorded and repaired as a variation, not absorbed silently.
Do you provide method statements for our safety file?
Yes — method statement, risk assessment and material safety datasheets before mobilisation.
We also work with
Talk to us about your main contractor project
An engineer visits, identifies the actual source, and gives you a written scope you can act on. 40+ years of Mumbai buildings.
Mon–Fri 08:00–18:00 · Sat 09:00–16:00 · Jogeshwari West