Can You Waterproof A Finished Basement?

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Water that finds its way into your finished basement can be a source of discomfort or may cause destruction to your wonderful space. How do you prevent or solve such a problem? We have consulted with the experts to provide you with the best answer.

Yes, you can waterproof a finished basement without breaking it apart. Two methods of doing so include:

  • Interior waterproofing
  • Exterior waterproofing

Continue reading as we tackle these waterproofing methods. Learn to keep your basement dry without demolishing it either partly or wholly. We'll also discuss the value waterproofing adds, and the costs involved. 

A wide shot of a finished basement, Can You Waterproof A Finished Basement?

How Do You Waterproof A Finished Basement?

Water seeping into your basement can be a nightmare, especially if it is habitable. The surest way to go about this is by waterproofing both the inside and outside of your basement. Let us delve further into how each is done.

Interior Basement Waterproofing

Whereas construction builders do all they can to waterproof a basement by installing a good drainage system, the soil can settle, creating cracks in the wall that causes water to seep through.

Also, concrete is generally porous and will absorb water from the soil, or a burst pipe will cause water to leak into the basement.

If you notice moisture or streaks of water on the walls, then they are signs water has found its way into your basement through the wall.

To curb this problem, sealing the wall is the most appropriate solution. But, before you go ahead, it is crucial to carry out a test to establish the source of the problem.

Condensation Test

Cracks can form at the bottom of a basement wall due to settling, and a test may be required to find the actual source of the moisture or water.

You can carry out a simple condensation test by drying the wet part of the wall with a rag. Afterward, take one square foot of aluminum foil and attach it to the wall with duct tape. Peel it off after 24 hours and check the underside.

If it is wet, water is seeping into your basement from the outside. If it is dry, the moisture originates from another part of your basement, like the basement shower.

The moisture or water can be prevented from entering the basement by doing the following:

1. Fill Cracks With Hydraulic Cement

Hydraulic cement contains properties that cause the cement to swell and set quickly. A heavy putty is formed by mixing the cement with water and then pressing it into the cracks using a putty knife. As this cement expands it goes deep into the cracks and crevices, forming a bond that is watertight.

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Follow the mixing and application directions because it sets very fast between 3 and 5 minutes after it is mixed.

2. Seal With Waterproof Paint

This type of paint seals the cracks and holes in the walls by applying a thick coat of paint on the wall surface with a roll or brush. Allow to dry and then apply a second coat. When you are done, it forms a watertight sealant to keep water away.

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Remove any paint that has previously been applied, because it adheres well on a bare concrete wall.
Removing the paint can be done using a wire brush or a sandblaster if the wall has several coats of paint.

Exterior Waterproofing

This is the best method of waterproofing your finished basement because it is non-intrusive and keeps the water from entering inside. The steps to do these are as follows:

1. Install A French Drain

A French drain is an effective method of waterproofing your basement to keep it dry by directing water away from the foundation before it finds a chance to make its way inside.

It involves laying a corrugated or perforated pipe in a shallow trench. Any excess water is drained away from the soil and around the foundation of your home and flows into a collection pit. From here, it is drained away from the foundation by gravity or a sump pump.

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This is where French drains come in. They drain water away from your basement. During the construction of French drains, gravel replaces the compact soil, helping further drain water, and reducing the pressure.

2. Install A Moisture Barrier And A Dimple Sheet

This is excellent watertight protection against water seeping through a wall. And the best part is that you do not need to interfere with the interior.

Protecting the basement foundation outside of a brick house from water and moisture

With this method, an exterior moisture barrier covers the exterior of your basement wall, finishing off with a dimple board. The dirt around is replaced with gravel to reduce hydrostatic pressure.

Does Waterproofing Your Basement Add Value To Your Home?

Excellent finished basement bar

Waterproofing your home is one of the best ways of upgrading the living conditions of the inhabitants. In addition, it is a great way to add value to your property at the time of selling it.

A basement that is well-maintained, in spite of it being hidden away from the rest of the home and possibly being smaller than most rooms, will increase the return on your investment.

The following are some reasons how waterproofing your basement can increase your property’s worth:

Extra Space

Your basement will be free of moisture and dampness due to waterproofing, hence you can turn it into a useful space like a guest room, office space, or for any other family activity.

Strong Foundation

A waterproofed basement prevents water from passing through the wall, which if it did, is capable of causing extensive damages to items made from wood. Mold and mildew will also thrive in a damp basement, and this can be a detriment to our health.

Save Energy

Any water that enters your basement will interfere with the proper working of your conditioning equipment. It will have to work harder and if lots of water find its way in, for example, during a heavy downpour, the conditioning system may end up getting destroyed.

Cozy Basement

Since waterproofing prevents moisture or water from entering a finished basement, it will be easier to keep it in good condition, creating a comfortable space.

Secure Your Investment

Buying a home is not cheap. This is all the more reason to keep it dry. You will avoid unnecessary repairs and subsequently save your money. Furthermore, when you need to sell it, the probability of fetching a good price is higher.

How Much Does It Cost To Waterproof A Finished Basement?

Finished basement of residential home with entertainment center, couch and flat screen television

As with most repairs, you will have to spend a considerable amount of money if you want a good job done.

Interior Waterproofing Costs

If you will be applying a concrete mixture to close the gaps and holes in the wall, the cost will range between $3.53 to $5.25 per square foot. 

And, if you are to seal your walls using paint, the costs will be between $0.61 to $0.87 per square foot, which includes preparing and cleaning the surface before painting. Applying waterproof paint is a job you can do by yourself, therefore the costs may be lower. 

It’s also important to note that if the exterior has not been waterproofed properly, the wall may allow in water, and the paint may start to disintegrate even 6 months later after application, further increasing the cost of repairs.

Always remember if you are not up to a task, get help from professionals.

Exterior Waterproofing Costs

Just like the interior, the costs will depend on the type of exterior waterproofing. For example, installing a French drain will cost between $10 to $25 per linear foot. 

On the other hand, if you want to apply a water barrier on the exterior wall, the costs range between $3 to $6 per square foot.

In Closing

Keeping your basement dry is one of the best things you can do for your home. It not only adds comfort but also value. If you decide to sell your home, you are more likely to receive a much higher return.

There are various methods of waterproofing your finished basement without disrupting its interior. The main goal is to keep water out. 

The costs for both interior and exterior waterproofing vary depending on factors such as the type of materials used, doing the work yourself or involving professionals, and how well the overall drainage system is. 

If you may want to find out how long waterproofing lasts and how to flex seal your basement, have a look at our previous posts: 

Can You Use Flex Seal To Waterproof Basement?

How Long Does Basement Waterproofing Last?

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