Foundation and basement waterproofing in Tbilisi
On site we spray the rubber membrane from outside while the pit is open — the only moment the wall is accessible. In an existing building we stop the water from inside with compounds that withstand its pressure.
What stops water at the foundation
Groundwater presses on the wall and slab from outside. Waterproofing, drainage and sealed joints only work together.
- 01Spray-applied rubber membrane outsideBitumen-rubber membrane ("liquid rubber"), two coats cold-sprayed over primer — on the wall and under the slab, carried above ground level. Seamless, flexible, bridges capillary cracks.
- 02Drainage membraneProtects the waterproofing during backfill and leads water down to the drain.
- 03Wall–slab cold jointA swelling waterstop in the concrete: the joint stays sealed as it moves.
- 04Perimeter drainRelieves water pressure from the structure so the waterproofing works as designed.
- 05Existing building — from insideWhen the outside is no longer accessible: crystalline compounds, crack injection, water plugs on active leaks.
Construction site, existing basement, joints
Foundation before backfill
- WHEN
- Basement walls and slab are cast, the pit is still open.
- WHAT WE DO
- Primer and two coats of spray-applied bitumen-rubber membrane on the wall and under the slab; where water presses, reinforced with geotextile. Drainage membrane on top, drain around the perimeter.
A basement that is already wet
- WHEN
- Efflorescence and damp patches low on the walls, water on the lowest floor, no access from outside.
- WHAT WE DO
- Active leaks — water plug and injection. Then from inside a crystalline or flexible cementitious compound: they withstand water pressure.
Cold joints, expansion joints, pipes
- WHEN
- Water comes along the wall–slab joint or around a service entry.
- WHAT WE DO
- On site — swelling waterstops in the concrete. In an existing building — joint injection and sealing of entries.
Six layers between the soil and the concrete
- 1Backfill — soil
- 2Drainage membrane
- 3Geotextile
- 4Spray-applied bitumen-rubber membrane (liquid rubber), 2 coats
- 5Primer
- 6Basement wall concrete
- MATERIALS
- Baumerk: spray-applied bitumen-rubber membranes, drainage membranes, swelling waterstops
- FROM INSIDE, IN AN EXISTING BUILDING
- Crystalline compounds close the concrete's capillaries and withstand water pressure; active leaks are first stopped with a water plug and injection.
- LIMITATION
- Outside — only before backfill. No compound bridges a moving joint on its own: that needs a separate detail.
Call us before backfill
The engineer looks at the pit, walls and joints and tells you what to do from outside while it is still possible. After backfill the same tasks are solved from inside — slower and more expensive.
Foundation questions
01The house is already built. Can you waterproof from outside?
Only by excavating the wall — usually more expensive than repair from inside and not always possible in the city. So in an existing building we work from inside: stop active leaks, then apply compounds that withstand groundwater pressure.
02Does inside waterproofing withstand water pressure?
Yes: crystalline and flexible cementitious compounds are designed for negative pressure — water pushing from the far side. What they cannot handle are moving cracks and joints: those need injection and a separate detail.
03What about pipe entries and cold joints?
On site we place swelling waterstops in the concrete before casting. In an existing building we inject the joint and seal the entry around the pipe. These are exactly the places that leak most often.
04Can a rubber membrane be sprayed onto a foundation?
Yes, it is our main method for basement walls and slab from outside: the bitumen-rubber membrane ("liquid rubber") is applied by cold airless spray in two coats over primer — a seamless flexible layer that bridges capillary cracks. Where water presses, we reinforce with geotextile or glass mesh and cover with a drainage membrane.
If you plan to do it yourself: which materials to use and how much to buy — in our guide on asbshop.ge.
Book a foundation inspection
The engineer finds where the water comes from and gives a written report with an estimate. Visit — 100 ₾, deducted from the estimate if you order the work.