Exterior Foundation Waterproofing

What This Service Involves

The most durable defense against a wet basement is stopping water at the outside of the wall, and that is exactly what exterior foundation waterproofing does. We excavate to the footing, clean and repair the concrete, then bond a waterproof membrane and drainage layer that channel water down to a perimeter drain. This approach suits Western Washington's heavy, sustained rainfall and clay-heavy soils that trap moisture against the house. It is more involved than interior methods but delivers the longest-lasting protection available. All excavation and backfill follow safe, code-compliant practice under our L&I license.

Benefits

Blocks water at the source before it touches the wall; Provides the longest-lasting waterproofing solution available; Pairs with footing drains for complete water management; Reduces efflorescence and dampness inside the home; Adds resale confidence for buyers wary of moisture

Our Process

1) Excavate along the foundation down to the footing; 2) Pressure-wash and patch cracks, tie rods, and honeycombing; 3) Apply the waterproof membrane and adhere protective drainage board; 4) Install or refresh the footing drain, then backfill and regrade to shed water

What Affects the Cost

Linear feet and depth of foundation exposed; Accessibility for excavation equipment on the lot; Landscaping, hardscape, or utilities that must be worked around; The membrane system specified for the job; New drain tile and discharge routing

Best Time of Year

This is best scheduled in summer or early fall when open trenches stay dry and backfill compacts properly before winter rains.