Waterproofing a 1,000-square-foot basement costs an average of $3,000–$10,000.* We’ll go over various cost factors and answer other important waterproofing questions in our guide.

If you live in an area with lots of rain and a high water table, you may notice water beginning to seep through your basement walls. Over time, excess moisture can cause mold, rust, and structural damage. You must waterproof your basement to stop leaks and other water seepage, sealing out moisture and draining away water before it gets in.

*Article cost data sourced from Angi, Fixr, and HomeAdvisor.

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What Are Signs You Need to Waterproof Your Basement?

Not all basements need waterproofing, particularly in areas where the water table is low and the climate is dry. However, it’s a good idea to look into basement waterproofing if you notice the following signs.

• Standing water: This is the most obvious sign. Waterproofing is probably immediately necessary if there’s often standing water in your basement.
• Water stains or discoloration: Check basement walls, floors, baseboards, and carpets for signs that water levels have risen and left stains.
• Efflorescence: This is the name given to the migration of salts, calcium oxide, and calcium hydroxide to concrete’s surface, where it dries. It looks like a white, powdery substance on walls and floors when the water has evaporated.
• Stale or musty odors: This is another sign that standing water or mold has been a problem.
• Rust: Check pipes, drains, and other metal hardware for signs of water-based corrosion.
• Outdoor water accumulation: If you notice water pooling in your yard near your home, it means the ground isn’t able to drain precipitation away from your foundation.

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What Factors Affect Basement Waterproofing Costs?

The total project cost depends on your home’s location, the size of your basement, and how you waterproof it.

• Basement size: The larger your basement, the more materials and labor are needed for waterproofing.
• Location: Waterproofing a basement interior typically costs less than waterproofing the exterior.
• Waterproofing method: Some waterproofing materials cost more than others.
• Geographic location: Waterproofing costs more in flood-prone areas.
• Labor: Professional contractors may charge by the job or per hour.

Basement Waterproofing Cost by Size

Waterproofing services typically cost $3–$10 per square foot of basement space. Where your project falls within that price range depends on your desired waterproofing methods and your basement’s layout. If parts of your basement are difficult to access or require extra work, the total cost increases. Here are some common cost ranges based on square footage.

Basement Size (sq feet)	Low End Price	High End Price
500	$1,500	$5,000
750	$2,250	$7,500
1,000	$3,000	$10,000
1,250	$3,750	$12,500
1,500	$4,500	$15,000
2,000	$6,000	$20,000

Cost of Interior vs. Exterior Sealing

There are three ways to waterproof a basement: install a drain on the interior floor just inside the wall, seal the exterior with a barrier between the foundation and the Earth, or install an exterior drain system to keep water away.

The interior basement is easier to access, so removing water costs less, usually $500–$10,000 for a 1,000-square-foot space. However, it’s generally less effective than keeping the water entirely out through exterior waterproofing, which typically costs $3,000–$15,000. This is a more involved process that requires excavation and specialized equipment. Many basement waterproofing projects combine both interior and exterior methods.

Basement Waterproofing Cost by Waterproofing Method

Your chosen waterproofing method largely depends on whether you’re waterproofing the basement interior or exterior. We’ll cover the specifics of each method in a later section. It’s important to note that multiple methods will likely be necessary.

Waterproofing Method	Location	Cost Range
Epoxy injection	Interior	$350–$500
Interior French drain installation	Interior	$40–$100
Sealant	Interior/exterior	$3–$7 per square foot
Sump pump installation	Interior	$300–$1,600 per square foot
Vapor barrier	Interior	$0.50–$0.70 per square foot
Exterior French drain installation	Exterior	$10–$100 per linear foot
Excavation	Exterior	$100–$200 per linear foot
Gutter installation	Exterior	$3–$30 per linear foot
Underground downspouts	Exterior	$100–$300 each
Window wells	Exterior	$3,000–$7,000 each
Yard grading	Exterior	$1–$2 per per square foot

Cost by Geographic Location

Basement water issues may be more or less likely depending on your location, and waterproofing costs will vary accordingly. If you live in an area with a high water table or lots of precipitation, you’ll have a harder time keeping your basement dry. Homes in these areas will require more extensive waterproofing, and local contractors will be more in demand. The International Residential Code may require homes in these areas to use exterior waterproofing solutions.

Basement Waterproofing Labor Cost

Most homeowners must hire professionals for basement waterproofing. The prices in this article include typical labor costs for the project. Keep in mind that any complications that increase project time will increase the total cost. Waterproofing contractors typically charge $200 per hour.

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How To Save Money on Basement Waterproofing Costs

Even if you hire pros, you can save money on basement waterproofing with the following tips.

• Take action as soon as you see signs of water damage. The longer you wait to fix it, the worse and more expensive the problem may get. Consult our list of tips for waterproofing your basement.
• Balance up-front costs with long-term benefits. Selecting cheaper materials may end up costing you more in the long run.
• Waterproof your basement before tackling other finishing jobs such as hanging drywall or installing flooring so that you won’t have to do it over.
• Keep gutters and downspouts clear so your gutter system can direct water away from your foundation.
• Get quotes from at least three different waterproofing contractors to compare before making your choice.

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What Are Additional Basement Waterproofing Cost Considerations?

Other factors can affect your total waterproofing cost. Learn more about each in the dropdown tabs below.

Age of Home

Older homes are generally more difficult and costly to repair. This holds true for basement waterproofing. Old basements have more potential for cracks and leaks and may not be up to current building codes. For example, homes built before the 1940s tend not to have support structures, called footings, around the foundation. These footings provide an easy location to anchor drains; without them, exterior waterproofing is more complicated.

Condition of Foundation

Problems with a home’s foundation are often expensive. If your foundation is in good shape, patching minor cracks may cost as little as $250. If your foundation has larger cracks or is uneven or sinking, it can cost upwards of $10,000 to fix. The average cost of foundation repair is $4,530. 

Drainage of Interior Water

You may need to install an interior drainage system for severe basement moisture problems. A contractor will line your basement floor with weeping tiles or pipe drains, creating a system in the slab floor that collects water and moves it to a pit for removal. Typically, a sump pump will then send this water out of the basement and away from your home and foundation. This usually costs $25–$55 per linear foot, and while it will get rid of standing water, it won’t prevent seepage from basement walls. Thus, it’s often combined with other waterproofing methods.

Excavation

Nearly all exterior waterproofing projects require digging in the ground with heavy machinery. This should be done by trained professionals at the rate of $50–$200 per cubic yard of dirt.

You may be able to rent the necessary machinery for $75–$350 per day for minor excavation projects. However, it’s quicker and safer to hire professionals since large digging projects can compromise your foundation’s structural integrity. Remember that most basement walls are 8 feet tall, with some or nearly all of that below grade level.

Foundation Type

Your foundation’s structure and materials can make waterproofing more or less complicated. For example, poured concrete walls are less prone to leaks than block walls because there aren’t any joints to become leaky. Thus, poured concrete foundations are typically less expensive to waterproof. However, concrete is porous and absorbs moisture, so even concrete walls can get wet and effloresce.

Gutters and Downspouts

Functional gutters are an important part of a home waterproofing system since gutters and their downspouts direct water away from the foundation and keep it from pooling near your home. Installing gutters typically costs $600–$1,550. Note that keeping gutters unclogged and relatively clean is key to proper function.

Making sure that water exiting the downspout is directed away from the foundation is critical. This may simply be achieved with splash blocks and grading but could also require downspout extensions and extended underground drains.

Mold

A wet basement will grow mold and mildew over time. If the problem is extensive, you may need mold remediation. Mold removal costs $1,500–$4,000 and must be done by a specialized professional. Mold can be extremely hazardous to your health, and a remediation contractor will know how to properly clean or remove tainted materials without spreading the spores throughout your house.

Waterproofing vs. Damp-Proofing

Damp-proofing is a less extensive process that prevents moisture from the soil from seeping in through basement walls and floors. It often involves installing some type of moisture barrier and filling cracks and joints. It costs less than full waterproofing—usually between $3 and $6 per square foot—but isn’t nearly as effective, particularly in damp climates. Keeping water out by treating the inside of the concrete is difficult if not impossible and can cause deterioration of the concrete walls.

Window Well Drains

A finished basement used as a living space must have an egress window in case of emergencies. These basement windows have window wells dug around them so they can open. If the wells lack proper drainage, water can pool and cause leaks. Installing window well drains usually costs $500–$2,000 per drain, while egress windows typically cost $3,500.

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What Are Common Types of Basement Waterproofing?

Many different tasks and products go into basement waterproofing. The ones you’ll need depend on your home’s specifics and whether you’re applying them to the basement’s interior or exterior.

Interior Sealing

Interior sealing solutions are applied on the inside of a basement’s exterior walls. These options are typically less costly and disruptive than exterior solutions, but they may be less effective on very damp ground.

• Waterproof paint: This is the least expensive waterproofing option. It can be applied to concrete surfaces for as little as $1–$2 per square foot. While it’s a good first step, it only protects against minor seepage.
• Concrete sealers: These substances are applied like paint but provide slightly stronger protection. Acrylic sealers are the least expensive ($3–$4 per square foot), followed by silicate sealers ($4–$6 per square foot ), and epoxy ($5–$7 per square foot).
• Vapor barriers: Instead of a coating, a vapor barrier is a separate plastic membrane that’s installed between the concrete of the walls and any finishing materials, such as drywall. The cost to encapsulate a crawl space or basement with vapor barriers is only 50 cents–70 cents, but it’s best applied by a professional.
• Interior drainage system: If water is a major problem, you may need an interior drainage system to remove it. This can consist of baseboard channels ($30 per linear foot), subfloor drain tiles ($25–$55 per square foot), an interior French drain ($60–$120 per linear foot), or a sump pump ($300–$1,600).
• Dehumidifier: Consider installing a dehumidifier to get rid of any remaining humidity in the air. This can cost $50–$1,000, depending on its size. Keep in mind that this won’t stop water from entering the basement, and it may actually pull in more damp air.

Exterior Sealing

Exterior solutions are applied to the outside of your basement. This almost always requires extensive excavation so contractors can reach the bottom of the foundation walls.

• Cementitious Coating: This cement-based sealant is a relatively inexpensive coating ($1,000–$1,500 to cover the whole basement). It’s easy to apply but dries hard and brittle, so it can crack over time. It works best in dry, sandy soil.
• Bentonite Clay: This material can absorb so much water that it eventually becomes waterproof. It can be packed around a home’s foundation for $3–$4 per square foot. However, bentonite can cause problems if it gets into drains, so it’s banned by some building codes.
• Exterior Drainage System: To direct runoff away from your home, a contractor can create a French drain ($1,000–$10,000) that allows water to seep into pipes where it can be pumped away.
• Waterproof Membrane: Similar to an interior vapor barrier, this rubberized asphalt membrane encases the foundation and blocks all moisture. It’s one of the most effective waterproofing solutions, particularly in damp climates. It’s also one of the most expensive (averaging $15,000) and must be professionally installed.
• Landscaping: It may be necessary to regrade your yard, changing relative elevations so that water flows away from your foundation. Yard grading typically costs $900–$3,000 and is usually paired with other basement waterproofing solutions.

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Can You Waterproof Your Basement Yourself?

Homeowners may be able to perform some simple waterproofing tasks, but more extensive projects should be left to the professionals.

Professional Basement Waterproofing

Although you’ll pay labor costs when hiring professional waterproofers, you’ll get the benefit of their experience, training, and equipment. Professionals can locate the source of small leaks and provide recommendations for sealing them, but water that seeps through walls and floors requires a larger solution.

Jobs that require excavation and pouring concrete almost certainly necessitate hiring professionals. Keep in mind that some waterproofing products must be professionally installed for the warranty to be valid.

DIY Basement Waterproofing

You may be able to take on some damp-proofing tasks yourself, such as applying waterproof paint or performing minor basement leak repairs. However, fully waterproofing a basement is a big project that requires several different skills. It’s also fairly high stakes since you could be setting yourself up for water damage if you don’t do it correctly. Waterproofing your basement, especially from the exterior, is best handled by professional contractors.

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Is Waterproofing Your Basement Worth It?

If you live in an area that’s prone to flooding or has a high water table, it’s a good idea to hire professionals to waterproof your basement. They can recommend the best course of action, whether that’s waterproofing the interior or digging around the exterior. Although this can be a pricey project, it will help protect your home investment in the long run.

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FAQs About Basement Waterproofing

Which is the cheapest basement waterproofing method?

The cheapest basement waterproofing method is waterproof paint. It will keep moisture from seeping through concrete and costs only $1–$2 per square foot. However, this is a limited form of damp proofing that won’t plug cracks or keep larger amounts of water out.

Does basement waterproofing increase home value?

Waterproofing your basement increases the amount of livable space in your home, thus improving its resale value.

How often should basement waterproofing be done?

How long basement waterproofing lasts depends on the materials and methods used. A coat of waterproof paint or sealant may only last a few years, whereas a new drainage system is a more permanent fix.

What are the common causes of water leaks in a basement?

Here are some of the most common causes of basement water leaks:

• Poor yard grading that drains runoff toward the house
• Cracks in the home’s foundation
• Ineffective or damaged gutter system
• Water leaks elsewhere in the home that cause humidity and basement condensation

How do I know if my basement needs waterproofing?

Here are some signs that you may need to waterproof your basement:

• Puddled water, either in the basement or around the exterior foundation
• Water stains or rust
• Mold and mildew
• Efflorescence
• Musty or stale odors

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