A variety of factors can affect your total crawl space encapsulation cost. Here’s a breakdown of the cost of this project, whether you hire a pro or DIY.
Basement Waterproofing Cost in St. Louis [2025 Data]
Normal Range: $1,431 - $5,097
Basement waterproofing in St. Louis, MO costs $3,248, on average, and most homeowners pay somewhere between $1,431 and $5,097 for a complete waterproofing system.
How we get this data
Photo: PhotoSerg / Adobe Stock Photography
Photo: PhotoSerg / Adobe Stock Photography
Highlights
Risks for frequent and severe flooding make basement waterproofing an important project for homeowners in St. Louis.
With risks for water intrusion high, more intensive waterproofing efforts like drainage and sump pumps are often recommended over simple membranes or sealants.
Lower labor costs help to keep basement waterproofing costs in St. Louis below the average.
The average basement waterproofing cost in St. Louis at $3,248, so homeowners can expect to pay between $1,431 and $5,097. The costs for this project vary depending on the type of waterproofing option you select. For instance, drainage and sump pumps can be more expensive in terms of labor and permits compared to simpler options like waterproof membranes and sealants. Continue reading to learn more about the costs associated with this project.
Basement Waterproofing Cost Factors
St. Louis's reputation for frequent and severe flooding means local homeowners need to be very diligent about basement waterproofing. In many cases, excavation for installing drains in and around a basement is necessary to divert large amounts of water away from the foundation. Your St. Louis basement waterproofing contractor will take factors like your basement's layout, your property's orientation, and existing signs of basement water damage that reveal entryways for water intrusion into account.
Basement Size
The cost to waterproof a basement falls between $3 and $10 per square foot on average, although where in this range your pricing falls depends largely on the type of waterproofing method you choose. In any case, large spaces require more time, labor, and material to waterproof than small spaces. Therefore, the larger your basement, the more you can expect to pay for waterproofing for any given method.
Below is a breakdown of how much you might spend for a range of basement sizes.
| Basement Size (Sq. Ft.) | Average Cost Range |
|---|---|
| 300 | $450–$1,500 |
| 500 | $750–$2,500 |
| 700 | $1,050–$3,500 |
| 900 | $1,350–$4,500 |
| 1000 | $1,500–$5,000 |
| 1200 | $1,800–$6,000 |
| 1500 | $2,250–$7,500 |
| 1700 | $2,550–$8,500 |
| 1900 | $2,850–$9,500 |
Interior vs. Exterior Waterproofing
Depending on where your basement water issues are stemming from and what solutions your expert recommends, you may need either interior or exterior waterproofing services. Some homes require both. Interior basement waterproofing is often more affordable because it doesn’t involve excavation and backfilling. Something like installing damp-proofing around the exterior of your foundation would require a lot of digging, which drastically increases labor costs.
You’ll spend an average of $3,000 on interior waterproofing services, while extensive exterior services will cost an average of $7,000.
Waterproofing Method
As mentioned above, professionals can waterproof your basement from the exterior or the interior. Exterior methods are more effective because they’re preventative, but they’re also more expensive because they tend to require excavation, which is time-consuming. The table below includes a list of basement waterproofing methods along with cost ranges for each.
| Waterproofing Method | Interior or Exterior | Average Cost Range |
|---|---|---|
| Epoxy injection | Interior | $500–$1,000 per crack |
| Sump pump | Interior | $800–$1,450 |
| Subfloor drain tile system | Interior | $20–$40 per square foot |
| Dehumidifiers | Interior | $500–$1,100 |
| Vapor barrier | Interior | $900–$2,000 |
| Weeping tiles / interior French drain | Exterior / Interior | $50–$90 per square foot |
| Baseboard channels | Interior | $20–$25 per linear foot |
| Yard grading | Exterior | $250–$2,200 |
| Gutter system | Exterior | $3–$30 per linear foot |
| Liquid membrane waterproofing | Exterior | $1.50–$5 per square foot |
Basement Waterproofing Pro Costs
Basement waterproofing companies in St. Louis charge clients based on the scope of each custom waterproofing project. Lower overall labor costs in St. Louis help to make waterproofing less expensive compared to many other cities.
Permits
Depending on how much excavation and structural work you need done for the waterproofing method you've chosen, you may or may not need permits. Permits are generally required in St. Louis when making structural alterations to your home's foundation or yard. In addition, any electrical work required for things like pumps or drains may require permits. Permits for this type of work range from $45 to $175.
Local Labor
On average, basement waterproofing professionals in St. Louis, MO charge between $98 and $130 per hour. Expect labor to increase for larger waterproofing projects that require a full crew compared to single-person projects that might include applying waterproofing sealants.
Taxes
All materials purchased locally for a basement waterproofing project could be subject to a 4.23% Missouri sales tax rate and a 5.45% St. Louis sales tax rate.
Insurance
Contractors in St. Louis are generally required to hold general liability insurance. If they have employees, they must carry workers' compensation insurance. Insurance premiums can cost the average local contractor $89 to $300 monthly.
Licensing and Certification
While Missouri doesn't have a statewide general contractor license, all contractors performing work in St. Louis must hold a Construction Industry Contractor Graduated Business License (GBL). Contractors incur costs of $24 for new licenses and $220 for annual renewals.
Does Basement Waterproofing Increase Home Value?
Yes, return on investment is high for basement waterproofing in St. Louis because the area is at risk for severe flooding. Basement waterproofing can help homeowners retain home value and avoid potential water damage restoration costs.
How Angi Gets Its Cost Data
Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We survey real Angi customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.
Want to help us improve our cost data? Send us a recent project quote to [email protected]. Quotes and personal information will not be shared publicly.
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