Retaining walls that leak into basements can cause significant damage to your foundation and interior spaces. When a retaining wall fails to manage water properly or begins to leak, moisture can seep into the basement, leading to dampness, mould growth, and potentially serious structural issues over time.
Leaks in retaining walls have serious implications for basements, often resulting in moisture problems, compromised stability, and costly repairs. Here’s why:
- Waterproofing Failures: Without proper waterproofing, or if the membrane has deteriorated, water can penetrate the retaining wall, seeping into the basement and creating damp conditions and mould growth.
- Clogged Drainage Systems: A blocked drainage system behind the wall causes water to build up. This pressure pushes moisture through cracks in the wall and into your basement.
- Hydrostatic Pressure: As water accumulates behind the wall, it creates hydrostatic pressure, which forces water through the wall, resulting in leaks and potential basement damage.
- Soil Instability: Water infiltration can weaken the soil around the wall, destabilising the structure and increasing the risk of water seeping into the basement.
- Flooding and Structural Damage: Continuous leaks can lead to basement flooding, which may cause long-term issues like mould, weakened foundations, and damage to the overall structure.
In short, when a retaining wall leaks, the problem extends beyond the wall itself, threatening the stability of your basement and potentially causing extensive damage. Prompt action is essential.
Client Project: Retaining Wall Rectification

Inspection
Inspection found no waterproofing applied to retaining wall – resulting in leaks on inside of basement walls.

Scope of Works
Rectify drainage under slab level and install waterproofing membrane system.

Bare Blockwork Post Excavation
Began with the raw, unfinished concrete or block material of the wall after excavation. At this stage, the wall is vulnerable to moisture absorption, so it must be properly treated to prevent damage.

Apply Epoxy Primer
The bare substrate was in poor condition and dirty, so we applied a strong Epoxy Primer. This thick, durable primer ensures that the waterproofing membrane adheres securely to the wall, enhancing its durability and moisture resistance.

Install Waterproofing Membrane
We applied a polyurethane membrane system to the wall. This membrane serves as the waterproofing layer, forming a barrier against water infiltration.

Corflute Installed & Tapped to Wall
Applied tough plastic corflute to protect the waterproofing system during backfilling, taping it securely to the wall. The corflute includes a drainage cell, with geofabric which acts like a filter which allows water to go through but dirt or earth can’t.
Need Help With a Leaky Retaining Wall?
If you’re dealing with leaks or suspect issues with your retaining wall, we offer expert waterproofing and repair services to get your wall back in shape. Don’t let water damage compromise your property—contact us today to schedule an inspection!