Below ground, water is not just falling on the structure — it is pressing against it, constantly. That changes what a waterproofing system has to do.
Water in the soil around a basement exerts hydrostatic pressure against the walls and slab from outside, all the time. A coating designed to shed rain off a terrace is not built to resist pressure pushing the other way, and it will lift off the substrate.
You see the result as damp at the base of the walls, white efflorescence blooming across the plaster, paint flaking in sheets, a musty smell that never quite clears — and after heavy rain, standing water.
There is also a difference between treating a basement from the outside and from the inside. Outside is better, because you are stopping the water before it reaches the structure. In an existing building it is usually not practical without excavation, so most of the work is negative-side: treating from within, using systems rated to hold against pressure rather than merely shed it.
Through the slab, through the wall, at the wall-slab junction, or through a specific crack or construction joint. These need different treatments and it is worth knowing which one you have before spending money.
Cracks and joints are cut, cleaned and sealed — often by injection — before anything is applied to the surface. A coating over an active crack is a temporary measure at best.
Where treating from outside is not possible, we use systems designed to bond to the substrate and hold against water pushing from behind.
If the surrounding ground is directing water toward the structure rather than away from it, we say so. Sometimes the cheapest real fix is outside the basement, not inside it.
The system is cured properly and then checked, ideally after a spell of rain.
Internal treatment solves a great many basement problems. It does not solve all of them. Where the water table, the drainage or the original construction means the only durable answer is external excavation and tanking, we will tell you that — including when it is the expensive answer you did not want.
We would rather lose the job than sell you an internal treatment we expect to fail.
The core technique for treating basement wall and joint leaks under pressure.
Underground sumps sit in the same conditions and fail in the same ways.
Worth checking together — water entering high up can appear at the lowest point of a building.
We will come and look, tell you what is actually causing it, and quote only what it needs.
Waterproofing, heat proofing and construction contractor based in Agra, Uttar Pradesh. 35+ years on site, authorised applicator for Sreechem Resins Limited, and a free inspection before any quote.
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