Leaking roof or terrace?
Flat concrete roofs, terraces, balconies and gutters.
Signs you'll see
- Brown stains or damp patches on the ceiling after rain
- Water dripping from light fittings or slab joints
- Ponding water that takes days to dry
- Cracked, blistered or peeling old membrane
Why it happens
- Membrane laps opening up after years of UV and heat
- Cracks in the slab from thermal movement
- Poor falls to outlets, so water sits on the roof
How we fix it
Clean, repair and prime
Remove loose membrane, fill cracks and apply bitumen or PU primer so the new layer bonds.
New membrane
4mm APP torch-on membrane with 10cm laps, or two coats of reinforced liquid PU membrane over the old roof.
Reflective protection
A UV-reflective topcoat keeps the roof cooler and protects the membrane from sun damage.
Products for roofs & terraces
Roofs & Terraces waterproofing questions
What is the best waterproofing for a flat concrete roof in Kenya?
For most flat concrete roofs, a 4mm APP torch-on bituminous membrane or a reinforced liquid polyurethane (PU) membrane works well. Torch-on suits large, plain roofs; liquid membranes suit roofs with many pipes, upstands or awkward details because they form a seamless layer. Both need a clean, primed slab and a UV-reflective or tiled protection layer.
Can you waterproof over an old leaking roof membrane?
Often, yes. Loose, blistered and debonded membrane is cut out, cracks are filled and the surface is primed, then a new membrane or two coats of reinforced liquid membrane go over the sound old layer. If the old membrane is failing across most of the roof, stripping it is the safer repair.
Why does my roof only leak during heavy rain?
Leaks that appear in heavy rain usually come from water ponding where the roof has poor falls, from open laps or cracks near outlets and parapets, or from blocked gutters overflowing onto the slab. Fixing the falls and outlets is as important as the membrane itself.
How long does roof waterproofing take?
A typical house roof is prepared and membraned in one to three dry days, depending on its size, how much old material must be removed and the weather. Liquid membranes need dry conditions between coats.
Want roofs & terraces done for you?
Book a site survey. We inspect, find the source of the leak and give you a written quote.