One of the most frequently asked questions we hear is how to stop flat concrete roofs from leaking?. Most commonly, the flat roof or balcony is over an inhabited area that the water leaks into when it rains. The problem not only occurs with concrete roofs but, is also experienced with bricks, pavers, or natural stone floors.
This commonly occurs because rain or moisture penetrates through the pores and capillaries in the floor to the area below. The moisture can also permeate through the grout or mortar between bricks or pavers. The solution is to apply a water-repellent sealer over the whole roof area. We recommend applying two coats of Concrete Sealer X-3. This is an impregnating silicone polymer that makes the concrete surface water-repellant after a 24-hour cure time. Apply two coats within 2 to 4 hours of each other, no longer. The sealer is invisible when it has dried and does not make the surface slippery.
If the rain or moisture is permeating through the floor through physical cracks then repair those areas first. Plug physical cracks with RX-1 Repair and Seal. This is a combination of a hydraulic cement with a built-in sealer. The hydraulic cement expands into the cracks or gaps. Simultaneously, this activates a built-in sealer to protect the repaired area. After the repair, Apply Concrete Sealer X-3 over the patched area plus the original area.