How Much Does Foundation Waterproofing Cost?
Foundation waterproofing costs $2,000 to $6,000 for sealing and coatings, and $10,000 to $18,000 for full exterior excavation with a membrane and drainage — roughly $80 to $200 per linear foot of foundation. Crack repairs run $250 to $800 each, and a French drain adds $1,500 to $6,000.
Foundation Waterproofing Cost — 2026 prices
Foundation waterproofing is priced by method and how much of the foundation must be accessed. Here is what 2026 jobs run.
| Foundation waterproofing job | Typical cost |
|---|---|
| Foundation crack repair Per crack, injection | $250 – $800 |
| Sealant & coating application Interior or accessible exterior | $2,000 – $6,000 |
| French drain / exterior drainage Redirect water away from footing | $1,500 – $6,000 |
| Exterior membrane + excavation Dig to footing, seal, drain | $10,000 – $18,000 |
| Per linear foot (exterior) Depends on depth & access | $80 – $200 / ft |
What you’re paying for
The cost hinges on access and depth. Sealing an accessible wall or injecting a crack is inexpensive. Excavating around a deep foundation to install an exterior membrane and drainage is labor-intensive — hence the jump to five figures. Landscaping, decks, or hardscape that must be removed and restored add to it.
Effective foundation waterproofing is really about water management: sealing the wall plus directing groundwater away with drainage and often a French drain, so hydrostatic pressure never builds against the foundation.
When it’s worth the exterior job
For minor dampness or a single crack, sealing or injection is usually enough. Persistent water intrusion, bowing walls, or a foundation under constant hydrostatic pressure justifies the exterior excavation approach despite the cost — it’s the most permanent solution and protects the structural integrity of the home. Get a foundation specialist to assess drainage and grading first; sometimes regrading and gutters solve much of the problem for far less.
Frequently asked questions
How much does foundation waterproofing cost?
What is the most effective foundation waterproofing method?
Does homeowners insurance cover foundation waterproofing?
About this data. Cost ranges reflect 2026 U.S. pricing aggregated from published restoration cost data and industry sources including HomeAdvisor, Angi, and Fixr. The calculator combines per-square-foot rates with water category, exposure time, and selected add-ons to produce a directional estimate. Figures are informational and are not a quote, appraisal, or insurance determination. Last reviewed July 2026.