Why is water coming through my foundation in Ghana?

Three causes account for almost all foundation leaks in Ghana: a seasonally high water table pushing groundwater against the structure, surface water not being drained away from the building, and the absence of external tanking when the foundation was built. Cracks from settlement or thermal movement then give that water a path through.

Can you waterproof a foundation from the inside?

You can, but it works against water pressure rather than with it. External tanking blocks water before it reaches the structure; internal treatment must resist the full hydrostatic pressure pushing inward. Internal systems using crystalline waterproofing or cementitious tanking do work when excavation is impossible, but external treatment is always the stronger solution where access allows.

How much does foundation waterproofing cost in Ghana?

Internal crystalline or cementitious tanking costs GHS 150-250 per square metre. External tanking costs GHS 200-350 per square metre plus excavation, which is often the larger figure. Localised crack injection to stop an active leak runs GHS 250-450 per linear metre. Improving surface drainage is far cheaper and should always be done first.

What should I fix before waterproofing a foundation?

Surface drainage. Ground sloping toward the building, blocked or missing downpipe discharge, paving that traps water against the wall, and a raised ground level bridging the damp-proof course cause more foundation damp than groundwater does. These are inexpensive to correct and often resolve the problem entirely.

Foundation Water Leakage in Ghana — Causes and Repair (2026)

August 30, 2026

Foundation Water Leakage — What Actually Causes It

Almost all foundation leaks in Ghana come from three things: a seasonally high water table, surface water not draining away from the building, or no external tanking when it was built. Fix drainage first — it is cheap, and it resolves a surprising number of cases outright.

The Three Causes

Cause	How you recognise it	Fix
High water table	Worse in rainy season; low-lying site	Tanking + drainage
Surface water	Appears within hours of heavy rain	Regrade, drainage — cheap
No tanking	Damp across the whole below-grade wall	Internal or external tanking
Structural crack	Water at a specific point, sometimes jetting	Crack injection
Leaking service	Constant, no seasonal pattern	Locate and repair the pipe

Do These Five Things First

They cost little and frequently solve the problem without any waterproofing at all.

Ground level. Soil or paving must sit at least 150 mm below the damp-proof course. Later landscaping frequently buries it.
Slope away from the building. The ground should fall away for at least 1 metre all round.
Downpipe discharge. A downpipe emptying at the wall base delivers the entire roof catchment straight to your foundation.
Paving. Hard paving butted to the wall traps water and drives splash-back. A gravel margin helps considerably.
Perimeter drainage. A French drain around the affected elevation is often cheaper than tanking and more effective.

Internal vs External Tanking

	External	Internal
Works	✅ With water pressure	⚠️ Against it
Protects structure	✅ Yes	❌ Wall stays wet
Excavation	⚠️ Required	✅ None
Disruption	High	✅ Low
Cost / m²	GHS 200–350 + excavation	GHS 150–250
Best when	Access exists; new build	Excavation impossible

External is always technically better — it stops water reaching the structure at all. But on an existing building surrounded by paving, driveways or a boundary wall, excavation is often impractical, and a well-installed internal system is the realistic answer.

Stopping an Active Leak Today

If water is coming through under pressure right now:

Clean loose material from the crack
Mix Plugging King hydraulic cement to a stiff putty
Press firmly into the crack and hold 30–60 seconds — it sets against flowing water
Allow 4–6 hours to cure

That stops the flow. It is not the repair — the water is still there, still under pressure, and will find the next weak point. Book a proper assessment.

Costs

Work	Cost
Drainage improvement	GHS 1,500–5,000
Crack injection	GHS 250–450 / lin m
Internal tanking	GHS 150–250 / m²
External tanking	GHS 200–350 / m² + dig
French drain	GHS 350–600 / lin m

Book a Foundation Survey

Free assessment covering ground levels, drainage, water table indicators and crack mapping — with a written report identifying the actual cause before we quote.

👉 Free Site Assessment · 0555 548 001

Related Resources

Back to blog

Item added to your cart