Interior Basements

How Much Does Basement Waterproofing Cost? (2024 Data)

Water in the basement can lead to issues such as mold and structural damage. Basement waterproofing costs can range anywhere from $2,300 to $7,575, with the national average at $4,920.
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Highlights

  • The typical cost range for basement waterproofing is between $2,300 and $7,575, with a national average cost of $4,920.
  • The main factors affecting basement waterproofing costs are the size of the basement, interior versus exterior sealing, the type of sealant that is used, labor costs, and geographic location.
  • Homeowners will want to consider basement waterproofing if they have noticed water stains, efflorescence, a musty odor, outdoor water accumulation, or rust in their basements.
  • Basement waterproofing is a complex project that most homeowners will want to leave to a professional who has the tools, knowledge, and experience to do the job correctly.
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A wet basement is never a good thing. When groundwater or moisture make their way into a sublevel, it can cause unpleasant smells, mold, and concrete deterioration. Luckily, homeowners can fight back against that moisture by waterproofing their basements. But how much does basement waterproofing cost? According to Angi, most homeowners pay between $2,300 and $7,575 or a national average of $4,920.

Costs will largely depend on how the space is waterproofed, as there are many options and techniques. Homeowners will need to decide whether to waterproof from the inside or outside, whether excavation is necessary, what products to use. All of these considerations, and many more, will affect the project budget and the outcome. This guide will explore these factors in more detail to help homeowners understand how to budget for this important project.

A black and green graph showing the national average and cost range for basement waterproofing.
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Waterproofing vs. Damp Proofing

There are two main types of moisture control used in basements: waterproofing and damp proofing. The terms are often used interchangeably, but they have totally different meanings.

Basement waterproofing is a method of keeping soil moisture and liquid water from penetrating a basement foundation or floor. This can be done with special membranes, cement coatings, and many other methods. According to HomeAdvisor, waterproofing basements costs between $5 and $10 per square foot.

Damp proofing simply fights soil moisture from soaking into the concrete, and most modern construction homes feature some degree of it already. It doesn’t do much for groundwater, but it can help a basement that would otherwise smell musty remain odor-free. If damp proofing is needed, homeowners can expect to pay between $3 and $6 per square foot.

Factors in Calculating Basement Waterproofing Cost

The average cost to waterproof a basement is $4,920. But like most home improvement and repair projects, basement waterproofing costs vary based on a myriad of factors, such as the following.

Basement Size and Layout

The size of the basement is a major factor in calculating waterproofing costs. A large basement will require more material, more time, and more labor than a smaller basement. Layout can also be a factor, but less so than the square footage. The following table gives homeowners an idea of how much it would cost to waterproof their basement based on its square footage.

Basement SizeWaterproofing Cost
500 square feet$2,500 to $5,000
750 square feet$3,800 to $7,500
1,000 square feet$5,000 to $10,000
1,250 square feet$6,300 to $12,500
1,500 square feet$7,500 to $15,000
2,000 square feet$10,000 to $20,000

Interior vs. Exterior Sealing

There are two places to stop water from penetrating basement walls: on the outside of the wall or on the inside. Interior sealing involves coating the inside of the basement walls with a waterproof sealant. Costs for interior basement sealing can range from $200 to $3,000. Exterior sealing involves digging down below the grade, exposing the foundation, and coating it or protecting it with a waterproof membrane. This method costs between $1,000 and $15,000. Exterior sealing is inherently more expensive. There is more labor involved, more equipment, and more time. But, it’s often the best way to keep water out of a basement.

Sealant Type

There are three main types of sealants that can be used for waterproofing basement walls: acrylic, epoxy, and silicate. The products and methods used to apply sealants have varying costs. For example, coating the interior of a basement with an acrylic paint is relatively inexpensive at $3 to $4 per square foot. The materials are affordable, and the labor is no more involved than traditional painting. Silicate can be sprayed on for about $4 to $6 per square foot. Epoxy is the priciest option and the most labor intensive, so prices are around $5 to $7 per square foot.

Meanwhile, using an exterior membrane to keep water out of the basement will cost much more. These membranes, the adhesives to apply them, and the labor and expertise involved in installing them are expensive. This is also often the most effective method, though it’s rarely a DIY job.

The cost ranges for basement waterproofing based on material.
Photo: bobvila.com

Labor

One of the most significant factors in budgeting for a basement waterproofing project is the labor. Contractors have payroll and bills to pay, overhead to carry, and profit to make. However, a contractor handles all the headaches and will provide reassurance that the project was completed correctly. There is the possibility of hiring a professional for basement waterproofing without the help of a contractor, which can slightly reduce costs. Most professionals charge between $3 and $8 per square foot for labor. In many cases, this price is included in the quote given by the professional. Homeowners can search for “basement waterproofing near me” to get a sense of local prices.

Geographic Location

For homeowners who live in an area of the country with a lower cost of living, the total project cost will likely be on the lower end of the spectrum. The same applies to more expensive areas: Steeper cost of living leads to steeper job costs. But in a region prone to flooding and high water tables, basement waterproofing costs might be higher.

The contractors in those regions are in demand, as homeowners need to protect their investments by keeping water out of their basements. For that reason, those contractors can charge higher rates. If that seems unreasonable, homeowners will need to understand that there is a greater risk involved for those contractors than contractors in drier regions.

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Additional Costs and Considerations

The method and labor involved in waterproofing a basement are the most obvious costs, but there are some additional costs that are unexpected. These factors can have at least some effect on the cost of basement waterproofing, and the more of them that are necessary, the more expensive the project will be.

Foundation Material and Condition

Concrete and block walls are incredibly tough and durable, but they’re not indestructible. In fact, concrete blocks have large voids inside them that can collect water. For that reason, contractors might need to drill weep holes in the bottom and allow them to drain into a drainage track.

If the foundation is in rough shape, no amount of waterproofing will work, and the structure can actually be unsafe. In that case, the walls will need to be repaired before the waterproofing job can move forward. The foundation repair cost will be extra, depending on how extensive the repairs are. But these repairs are crucial to ensure a waterproof foundation.

Home Age

The home’s age might have something to do with what routes are viable when waterproofing a basement. Homes built before the 1960s might not have footers under their foundations, which are essentially concrete walls below the surface with flared “feet” to both anchor the foundation in the soil and disperse the weight.

If the home has footings, a contractor can dig down to those footings and install a water tunnel on top of it. This gives water a way to run off of the foundation wall instead of penetrating the wall.

Repairs

Very often, the source of water and moisture in a basement is a crack (or several cracks) in the floor, walls, or foundation. While the walls may still be strong and stable, water squeezes its way through those cracks from the soil outside, leaving the basement a dirty, wet mess. Before ensuring a waterproof basement, those cracks need to be addressed. It can cost as much as $7,000 to repair foundation cracks in addition to waterproofing. If it is a block-wall foundation, this will result in an even higher overall cost. There are DIY kits that users can buy, but fully repairing the crack will likely require a professional’s touch.

Mold Remediation

The dreaded byproduct of water in a home: Mold. Mold spores exist everywhere, but damp, dingy, dark, wet basements are the perfect breeding ground for an infestation. Mold can cause serious health issues, so if there is mold in the basement, the homeowner cannot ignore it.

If it’s a very small section (under 10 square feet), the homeowner can attempt to tackle the job. If not, mold removal is another cost to factor in. This type of work requires personnel specifically trained and licensed in mold removal. Mold remediation costs anywhere between $1,125 and $3,345.

Water Table Level

In some cases, simply patching a few cracks will be all the waterproofing that is necessary to maintain a dry basement. But in areas with high water tables, the International Residential Code (an international guide for building safety) actually requires waterproofing.

The water table is the level below grade where the ground is saturated with water. There are many reasons why an area might have a high or low water table, but the former can be expensive to combat. These areas don’t shed rain or groundwater very well, and a basement is often the route of least resistance. For that reason, exterior waterproofing efforts might be the only option.

Interior Water Drainage

In some cases, it makes the most sense to control water rather than just waterproofing a basement. For those applications, adding some interior water drainage methods might do the trick. This usually includes excavating a small trench (around 6 to 8 inches deep and wide) that slopes to a drain or a sump pump. Otherwise drainage pipes can be added to the walls for $0.95 to $2.80 per linear foot to direct water to the sump pump.

In the case of block walls, interior drainage is quite popular. Cutting and removing the concrete along the base of the wall and carefully drilling weep holes allows the trapped water to drain into a control channel. The sump pump or actual drain will remove that water from the basement. If the home does not already have a sump pump, these can cost $490 to $1,170 to install.

Landscape Grading

Homeowners might not want to hear it, but their landscaping could be doing more harm than good. And even if it isn’t the cause of a flooded basement, some well-planned regrading can help reduce the issue. Hiring one of the best landscaping companies to regrade the landscaping around a home can help the home shed water away from the foundation before it can soak in. This can go a long way toward waterproofing a basement, but it takes special engineering skills and knowledge of soils and aggregates. The first step is removing any standing water in the yard, which costs $1,000 to $3,000. After that, a typical grading job can cost between $1,400 and $5,200.

Gutter and Downspout Additions

Some homeowners don’t understand the important role that their gutters play in keeping the basement dry. In some cases, that’s their main purpose. Without gutters, the massive amount of rain that a roof can collect in a rainstorm will drip down the shingles and land no more than a foot from the foundation walls—a perfect recipe for a wet basement.

Ensuring that the home’s gutters are pitched correctly and free from clogs and debris is essential, or else water will back up over the brim of the gutter and drop in front of the foundation. Also, downspouts need to shed the collected rainwater at least 8 feet away from the foundation. Installing exterior or interior drainage, and ensuring the gutters are operating as they should be, are all important points for homeowners to consider. These costs can run up to be a few hundred dollars. Gutter installation cost is relatively affordable with an average range of $600 to $1,550.

Excavation

Many of the solutions or situations listed above require excavation to solve the issue in order for the foundation to be accessible. This usually takes 2 to 3 days to complete. Whether it be exterior waterproofing via a membrane, installing a water channel, or regrading the landscaping, they all require some knowledge and heavy equipment. Even if a homeowner rents the equipment and does it themselves, it’s an expense of about $75 to $350 per day to factor into the total basement waterproofing cost.

Excavation companies know how and where to dig without causing more issues than they’re solving. They’re also insured, which means that anything that could potentially go wrong will be on them. Expect to pay between $50 and $200 per cubic yard of dirt for professional excavation.

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Basement Waterproofing Cost by Method

There are several ways to waterproof a basement, and they take place on both sides of the wall. For instance, exterior waterproofing could include laying a membrane against the foundation walls below grade or installing a drain system on the footer. Unfortunately, these particular methods require excavating and can be a handful for a DIYer.

There are different methods to use on the inside. Pros might dig trenches around the perimeter of the basement and install drains for groundwater to run through. There’s also the possibility of sealing the walls with a waterproof coating.

Basement Waterproofing MethodAverage Cost
Cement waterproofing$1,000 to $1,500
Foundation membrane$15,000
Weeping tiles$1,000 to $10,000
Bentonite clay$3 to $4 per square foot
Coatings$3 to $12 per square foot
Silicate concrete sealers$3 to $9 per square foot
Paint$30 to $40 per gallon
Vapor barrier$1,500 to $3,000
Baseboard channels$30 per linear foot
Subfloor drain tile system$25 to $55 per square foot

Exterior Sealing

Exterior sealing involves working on the outside of the foundation walls. Because most of the foundation wall is typically buried below grade, this requires some excavation and careful digging. There are also different types of waterproofing materials used on the outside of the foundation, each with its own application method and tools. So how much does it cost to waterproof a basement from the exterior? There are a wide range of options and costs, with some reaching up to $15,000.

  • Cement waterproofing: Cement waterproofing involves mixing bags of cementitious mix and coating the surface with a thick layer. This is an easier and less expensive method than most other options, but the results can be hit or miss. The concrete mix doesn’t always adhere, and if the foundation settles or shifts, it’s likely to crack. Depending on the size of the home, cement waterproofing can cost between $1,000 and $1,500.
  • Foundation membrane: Foundation membranes are the heavy-hitters of the exterior waterproofing game. These membranes are thick sheets of rubberized asphalt on waterproof polyethylene film. It has to be installed just right in order to work properly, but it’s usually the most effective method of exterior basement waterproofing. Beware that this method is pretty expensive, costing up to $15,000.
  • Weeping tiles: “Weeping tiles” is a somewhat confusing term, as they aren’t tiles but pipes with a series of holes drilled in them. They install below ground around the perimeter of a home. Once water enters the holes, the pipes drain it away from the foundation, removing it before it has a chance to penetrate. This is sometimes the most cost-effective and DIY-friendly option, but it doesn’t always solve the issue. The cost to install weeping tiles can be between $1,000 and $10,000, depending on excavation and depth.
  • Bentonite clay: Bentonite clay is an extremely absorbent material that can grow to 15 times its original size when saturated with enough water. And, once it hits its maximum size, it becomes so dense that water can’t travel through it. Waterproofing with this clay includes laying it along a trench outside the foundation, but it requires a lot of bentonite clay. It can also be installed between two porous sheets that allow water to pass through the sheets but not the clay, though this often requires an expert touch. Bentonite clay waterproofing costs a national average of around $3 or $4 per square foot.

Interior Sealing

It’s also possible to waterproof a basement from inside. In general, this includes either sealing off the surface with a waterproof paint, controlling the flow of water into a drain, or keeping moisture from settling within the space. Each solution has its place, so it’s important for homeowners to consider them all.

  • Coatings: There are certain coatings that DIYers and pros can use to waterproof basement flooring and walls to keep water from making its way in. They’re either concrete-based or an acrylic/epoxy mix. The concrete is less expensive, but the acrylic or epoxy mix adheres better and is totally waterproof. Homeowners can expect to pay between $3 and $12 per square foot.
  • Silicate concrete sealers: Another attractive option includes using a silicate concrete sealer, which penetrates into the concrete surface and causes a chemical reaction that makes the concrete much less absorbent. These products are inexpensive and relatively easy to apply, and since they penetrate, they will hardly change the look of the wall when dry. The materials might only cost $0.15 to $0.25 per square foot, but professional installation bumps the price up to $3 to $9 per square foot.
  • Paint: The easiest and usually least expensive option for waterproofing is painting the interior walls and floor of the basement with a waterproof paint. These paints are typically acrylic-based and adhere well while also creating a barrier against water. Application is as easy as with typical painting methods. Most basement waterproofing paints only cost $30 to $40 a gallon, and they’re easy to apply.
  • Vapor barrier: When it’s moisture that’s an issue, not necessarily water flow, a vapor barrier might be all it takes to waterproof a basement. These plastic sheets keep moisture on the outside instead of letting it into the house. They can be installed on the inside of concrete walls and floors, but also in basement crawl spaces. A vapor barrier installation can cost between $1,500 and $3,000.
  • Baseboard channels: Baseboard channels are an attractive option for block walls; the installer can drill a few weep holes in the wall and then cover them with the baseboard channel. The channel acts as a gutter and runs toward a sump pump or train, keeping the rest of the basement dry. This process can cost around $30 per linear foot for a professional.
  • Subfloor drain tile system: Finally, protect finished surfaces by lifting them up off the ground with a subfloor drain tile system. These interlocking tiles are made from waterproof materials and offer an inch or two of space between the concrete floor and the finished floor above. This option does nothing to stop the water from entering the basement, so a moisture barrier is required. Homeowners can expect to budget $25 to $55 per square foot.
A view of a worker painting a home's foundation.
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Do I need basement waterproofing?

Not all basements require waterproofing. In most cases, the standard damp-proofing methods can keep the basement dry. But homeowners who are unsure if they need basement waterproofing, there are some telltale signs to look for.

Typically, homeowners can look for stains on the walls or floor and they’ll tell them water was present. Discolorations in carpets, drywall, and wood surfaces would indicate that the water level either rose enough at one point to cause an issue. It’s also a good idea to keep a nose out for musty odors.

Any of these signs would indicate that it’s time to consider some waterproofing. Before looking into the cost to finish a basement, it is absolutely essential for a homeowner to solve any outstanding water issues to avoid costly repairs down the road. Also, those odors might be a sign of mold, which is not something anyone wants hanging around their subterranean spaces.

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Water Stains

Noticing stains on the basement walls, floors, wood, or carpet is usually an obvious sign that water was present and it’s time to consider some sort of waterproofing to prevent it. Homeowners will want to keep track of where those stains are, as it might be possible to make waterproofing repairs in that area alone.

Efflorescence

Efflorescence can look scary, but in and of itself, it’s rather harmless. This white, powdery substance is actually crystallized minerals (namely salt) that remain from after groundwater penetrates the basement walls or floor and then recedes. While the efflorescence is harmless, the water that brought it there might not be, and it’s worth considering waterproofing.

Musty Odor

Other than wet, soaked surfaces, musty odors can be the telltale sign of water in a basement. Aside from finished spaces, basements aren’t particularly cozy. But they don’t become stinky and musty without a reason. The stale, soily smells can also be a sign of mold, so it’s probably a good time for a homeowner to find the smell and consider some waterproofing, and call one of the best mold removal companies (such as ServiceMaster Restore or ServPro) to take care of the problem.

Outdoor Water Accumulation

Accumulating water on the outside of the home, whether it be the garden beds, the driveway, or even puddles in the yard, can be a sign of a high water table. While the table might ebb and flow throughout the year, this might be a sign that a homeowner needs to think about waterproofing.

Rust

Rust might not be the first thing that comes to a homeowner’s mind when it comes to concrete basements, but it’s certainly worth watching for. The humidity caused by water in the basement will settle on every surface, including steel drain pipes, metal pipe hangers, and other metal surfaces. That moisture will cause corrosion, so seeing rusty metal in the basement is a pretty good sign of a water issue.

Basement Waterproofing: DIY vs. Hiring a Professional

Waterproofing a basement is a big project. While it can be within the capabilities of some very experienced DIYers, it’s not advised for the average homeowner, and it might be best to hire a professional. A contractor will be able to identify where the water is coming from and decide which method and products are the most appropriate. They’ll also be able to handle repairs on the exterior of the home, including excavating around the home and installing the waterproofing products properly.

And proper installation definitely matters. For many waterproofing systems, the manufacturer requires a licensed professional to install them. They’re so serious about this that they won’t warranty the product if a professional contractor didn’t install it. That means a homeowner could potentially rent the equipment and spend the time digging and waterproofing the basement only to find that it didn’t work and the finished basement flooded. Homeowners insurance may cover water damage provided it’s caused by a covered event, but the homeowner will have to pay to have the entire basement waterproofed again, and they won’t be reimbursed for their time. For all of these reasons, it’s wise for a homeowner to carefully consider the pros and cons of DIY vs hiring one of the best basement waterproofing companies (such as Basement Systems or B-Dry).

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How to Pay for and Save Money on Basement Waterproofing

Basement waterproofing is not the most exciting element of basement remodel cost. However, there are some simple fixes homeowners can undertake to save some significant money on basement waterproofing cost.

  • Shop around: Get quotes from at least three basement waterproofing companies to find the best available prices.
  • Read reviews: The last thing anyone wants is to pay a premium for shoddy workmanship and have to have the work done over again. Thoroughly vet the waterproofing company before scheduling service with them.
  • Try DIY: Take care of small repairs yourself instead of paying a contractor to do it.
  • Fix the gutters first: Make sure that the downspouts are draining 8 feet or more from the basement. Optimizing drainage may resolve the issue.
  • Opt for spot repairs: Only waterproof the areas that are leaking.
  • Don’t ignore the warning signs: If you see signs of water damage in your basement already, it’s best to take care of the problem straight away. Letting the damage fester can lead to higher cost of repair later down the line.

Although basement waterproofing isn’t the most expensive project, homeowners may need assistance to pay for this essential home service. Here are some options:

  • Credit card: Homeowners with “very good” or “excellent” credit scores may be able to qualify for a credit card with a 0 percent introductory rate. Using this type of card and paying the balance before the intro period ends can help homeowners save.
  • Personal loan: Homeowners can consider taking out one of the best personal loans to pay for basement waterproofing.
  • Home equity loan or line of credit: When facing a more expensive basement waterproofing project, homeowners can tap into their home for financing. Homeowners can look into one of the best home equity loans (such as a loan from U.S. Bank or Flagstar Bank) or one of the best home equity lines of credit (HELOC) to fund the work.

Questions to Ask About Basement Waterproofing

Homeowners who decide to hire a contractor will want to ask some important questions before landing on one. Some questions for homeowners to ask include the following.

  • Can I see proof of your insurance?
  • How long have you been in business?
  • Do you have references for similar projects?
  • Which products do you use?
  • Do you take care of cleanup after the work is complete?
  • Is there any possibility of additional costs?
  • Can you explain why this basement waterproofing method is right for my home?
  • Do you offer a warranty on your work?
A close up of basement waterproofing material.
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FAQs

With all that background on basement waterproofing costs, homeowners might have some additional questions. This section will address the most frequently asked questions on the topic.

Q. How can I stop water from coming into my basement?

There are many different ways to waterproof a basement, including: Adding interior coatings, cutting drains into the floor, regrading the exterior landscape, and installing a waterproof membrane on the outside of the foundation,

Q. Can I seal my basement interior?

A homeowner can absolutely seal the interior of a basement. This is best done with a sealer or special paint with an acrylic or epoxy base. It’s also a good idea to use a concrete crack filler to take care of any cracks or separations in the floor or walls of the basement.

Q. Is basement waterproofing covered by insurance?

Most homeowners insurance policies will not cover waterproofing expenses. Because it’s likely insurance won’t even cover flooded basement cleanup costs, looking to insurance for coverage is probably not the answer to the water issue.

Q. Should I waterproof my basement on the inside or on the outside?

This decision will depend on a homeowner’s budget as well as where the water is coming from. The cost to waterproof a basement from the inside is typically lower, and this method will usually suffice for protecting the basement from humidity and moisture. If there are drainage problems on the home’s exterior, however, waterproofing on the outside will solve the problem at its source.

Q. How long does it take to waterproof a basement?

Depending on the method, most waterproofing jobs take between 1 and 3 days to complete. If excavation is needed, homeowners can expect the project to be on the lengthier side.

Q. Will waterproofing my basement increase my home value?

Waterproofing the basement may or may not increase home value; however, solving a water damage or moisture issue in the home’s basement will make it more attractive to potential buyers.

HomeAdvisor, Angi, Thumbtack, Fixr, HomeGuide