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Porous Concrete Walls Explained

As a homeowner, you may be surprised to learn your porous walls are a factor responsible for the high humidity and water in your basement.

How? Although strong, concrete is actually porous. At least 18 percent of the concrete making up your foundation is microscopic pores that allow water and water vapor to pass.

Why Is Concrete Porous?

There is a lot of water in the concrete mix and when the concrete is poured and it begins to cure, that water begins to evaporate. During this process, it leaves a trail of capillary pores in the concrete. These pores are invisible to us, but they are larger than water molecules. This means that water vapor can pass through them.

In time, the volume of water infiltrating your walls will increase. Why is that? Well, cement paste that is in the concrete contains calcium that dissolves in water. Therefore, when water gets into the pores they slowly get larger and larger. In the end, you will struggle to remove the moisture from your basement.

Solving Porous Concrete Problems with Waterproofing

Installing waterproofing measures is always a step in the right direction. Even if you do not have any moisture issues now, that doesn’t mean that these problems won’t pop up in the future. When they do it’s not enough to remove the water itself, it’s also necessary to create a drainage system that will remove the water as soon as it enters the home without damaging the foundation or the walls.

Interior Drainage System

To maintain a dry basement, you should consider installing an interior drainage system. BasementGutter™ is a high-quality system that runs along the perimeter of the basement and collects excess water that seeps through the porous walls before it gets a chance to cause damage. It is installed without any soil excavation, which makes it a much better solution than an exterior drainage system. It can also be installed much faster and is more affordable.

BasementGutter™ goes below the floor, so it is barely visible once it is in place. This makes it ideal for both finished and unfinished basements. It has a clog-free design and it won’t get blocked by debris over time.

Basement Sump Pump

A sump pump can quickly and easily discharge large volumes of water from your basement. Our sump pump systems come in various sizes and configurations, to find one best for your home. It is recommended to invest in a battery backup sump pump as well. This way you can be at ease in case of a power outage.

Vapor Barrier

If the pores in your concrete basement walls are letting large amounts of water into your basement, covering them with a vapor barrier is a good option. The thick and durable barrier, WallSeal™, easily attaches to the wall so that any leaks run behind it and end up in the interior drainage system. With this system, your basement will stay nice and dry.


If with all of these waterproofing measures there are still increased humidity levels in your basement, a dehumidifier can solve this problem for good. While it cannot keep your basement dry on its own, it works amazingly well with other waterproofing solutions. This device will regulate humidity levels in the basement and keep them under control.

Although you can find standard dehumidifiers in various big-box stores, contacting a foundation specialist to install a unit designed specifically for foundations is the best route.

Combining a sump pump with a dehumidifier is a great solution since all the water from the dehumidifier will be directed into the sump pit and there won’t be any containers that need to be emptied.

Waterproofing your basement can even lower your heating and cooling bills. If you wish to learn more about these solutions, contact a foundation specialist in your areas and schedule a free assessment and quote.