Basement waterproofing cost per linear foot
| Drain system | Installed price | Good to know |
|---|---|---|
| Interior drain along the wall (drain tile or baseboard channel) | $40–$120 | Collects water inside the footing and carries it to a sump |
| Exterior French drain along the foundation | $10–$100 | Dug along the outside of the foundation; drains water away from it |
The guides disagree widely on the whole-basement total: Angi puts the average at $5,242, Fixr and Forbes about $5,000, HomeGuide interior work at $6,000 to $12,000 and This Old House $13,640 for a 1,000 sq ft basement. A full-perimeter drain at per-foot prices lands well above the lower averages, so we price by the linear foot. Measure the walls that take on water and the calculator does the rest. Whole exterior waterproofing is quoted per project (Angi about $7,000, HomeGuide $10,000 to $18,000), so it is not modeled.
What changes the price
- Interior or exterior. An exterior system means digging along the foundation; an interior system works from inside.
- Length of wall. The drain is priced by the linear foot, so treating one wall costs a fraction of the whole perimeter.
- Sump pump. An interior drain needs somewhere to send the water, and a sump pump is a separate line.
- Cracks. Epoxy injection is priced per crack.
- Grading. Regrading the yard so water runs away from the house is priced separately and can be done first.
- Where you live. The calculator adjusts the labor share for your state's construction laborer wages.
Extras to expect
| Item | Typical cost | When it applies |
|---|---|---|
| Sump pump and pit | $600–$2,500 | Interior drains that send water to a pit |
| Epoxy crack injection | $250–$1,500 per crack | Active leaks through a foundation crack |
| Regrading the yard | $500–$5,000 | Water pooling toward the house |
| Vapor barrier | $1,500–$3,000 | Damp walls or floors |
Sealants and membranes are priced by wall area
Surface treatments are quoted per square foot of wall, not per linear foot. Angi lists waterproofing paint at $1 to $8 and silicate concrete sealer at $3 to $9 per square foot, liquid membrane at $3 to $6 and sodium bentonite at $3 to $4. HomeGuide lists sealant at $2 to $10 and waterproof membrane at $4 to $7 per square foot installed. These are not in the calculator because they depend on the height of the wall you treat.
Water in a basement can come from several places. See sump pump installation cost, French drain installation cost, foundation repair cost and crawl space repair cost. Clean gutters keep roof water away from the foundation; see gutter cleaning cost.
Questions to ask before you hire
- Where is the water coming from, and how did you find the source?
- Which walls will you treat, and how many linear feet is the quote for?
- Does the price include the sump pump, the discharge line and cleanup?
- What does the warranty cover, and does it transfer if I sell the house?
- Can fixing the grading or gutters solve the problem first?
Methodology and sources
We price each drain system per linear foot from the published guides, take the middle of their lows, midpoints and highs, and adjust the labor share for your state's wages. This Old House draws on Angi and Homewyse, so it is not counted separately. Forbes Home is used as an independent cross-check. Read how we estimate costs.
- Angi: basement waterproofing cost — drains per linear foot, sump pump, crack injection, grading, vapor barrier
- Fixr: basement waterproofing cost — drains per linear foot, sump pump, crack injection
- HomeGuide: basement waterproofing cost — exterior drain, sump pump, crack injection, grading
- This Old House: basement waterproofing cost — whole-basement average, repeats Angi
- Forbes Home: basement waterproofing cost — used as an independent cross-check
- BLS OEWS May 2025, State (SOC 47-2061, Construction Laborers) — state labor index, used as a site-work proxy
What each source reports
Our estimate does not rely on any single page. This table lists each page we used and the figures it reports, so you can see where the ranges come from.
| Source | What it reports |
|---|---|
| Angi |
|
| Fixr |
|
| HomeGuide |
|
Common questions about basement waterproofing costs
How much does basement waterproofing cost?
A typical job (100 ft, interior drain) comes to about $8,500 nationally, within a range of $4,000 to $12,000. Use the calculator above to adjust for your state, the options you choose and any extras.
How much does it cost to put an interior drain along 100 feet of basement wall?
About $4,000–$12,000, at $40–$120 per linear foot. With a sump pump added, 100 feet comes to $4,600–$14,500.
What is the interior basement waterproofing cost per linear foot?
About $40–$120 per linear foot for a drain tile or baseboard channel system. Angi puts it at $60 to $120 and Fixr at $40 to $120.
How much does exterior basement waterproofing cost?
An exterior French drain costs about $10–$100 per linear foot. Waterproofing the whole exterior wall is quoted per project: Angi puts extensive exterior work at about $7,000 and HomeGuide at $10,000 to $18,000.
Is interior or exterior waterproofing cheaper?
Per linear foot, an interior drain costs more ($40–$120) than an exterior French drain ($10–$100), but the two do different jobs. Across a whole project, Angi puts interior work at about $3,000 and extensive exterior work at about $7,000.
How much does a sump pump add to the cost?
About $600–$2,500 for the pump and pit. An interior drain needs somewhere to send the water, usually a sump pump. See the sump pump installation cost page.
How much does it cost to repair a leaking foundation crack?
Epoxy injection costs about $250–$1,500 per crack. Angi quotes $800 to $1,500, while Fixr and HomeGuide start at $250.
How much does waterproof paint or sealant cost?
Sealants and paint are priced by wall area, not by the linear foot: Angi lists waterproofing paint at $1 to $8 per square foot and silicate concrete sealer at $3 to $9, and HomeGuide lists sealant at $2 to $10. Our calculator does not model them.
Why are the guides so far apart on the total?
Whole-basement averages run from about $5,000 at Fixr and Forbes to $13,640 at This Old House for a 1,000 sq ft basement, because the guides price different jobs. We price the drain by the linear foot so you can match it to your own walls.
Where do these prices come from?
They come from 3 published cost pages from 3 publishers, last checked Oct 9, 2026. We report what those pages say and do not invent figures; the table above shows each source.
How does my state change the estimate?
The labor part of the price is scaled by the average wage for the relevant trade in your state, using Bureau of Labor Statistics data. Materials and equipment are not adjusted.
Why might a contractor's quote differ from this estimate?
A quote reflects your specific scope, access, local demand and what the contractor includes. Ask for line items rather than a single total so you can compare bids on the same basis.
All 3 sources behind these prices
Every figure in the calculator comes from one or more of these pages, with the number each one supports in the link text.