Basement Waterproofing and Soil Stabilization at Earthen Wall to Block Wall Intersection

Problem

In Aberdeen, WA, a daylight basement corner located at the intersection of an earthen wall and a block wall was experiencing significant water leakage due to soil erosion. The sloping terrain naturally directed water toward the 100-year-old house, exacerbating the issue and causing void-like conditions in the soil below the surface. Probing revealed that the top 1.5 feet of soil was relatively solid, while the next 2 feet were significantly compromised, approaching a void state. This unique situation presented a challenge in basement waterproofing and soil stabilization, as earthen wall to block wall intersections are rare and require specialized solutions. Groundworks was contacted to resolve this problem.

Solution

NCFI’s Terra-Lok™ 24–120 polyurethane system was utilized for permeation grouting to address both the water infiltration and the compromised soil conditions. The injection was done from the exterior of the south wall. The material formed a durable, impermeable grout curtain, effectively sealing the basement corner against water intrusion. The application also stabilized the surrounding soil, preventing further erosion and mitigating the effects of the natural slope directing water toward the house.

Results

The project successfully:

1. Waterproofed the basement corner: The intersection between the earthen and block wall was sealed, stopping water intrusion entirely.
2. Stabilized the soil: The permeation grouting filled void-like spaces in the soil, halting erosion and reinforcing the ground stability.
3. Delivered a long-lasting solution: The Terra-Lok™ 24–120 system provided a permanent waterproofing and stabilization method suitable for this complex scenario.

This project highlighted the versatility of Terra-Lok™ 24–120 polyurethane in tackling unique and challenging waterproofing situations.