6 Causes of Basement Moisture (and How to Fix Them)

6 Causes of Basement Moisture (and How to Fix Them)

Basement Moisture
Got a wet basement? Basement moisture is not an uncommon problem. In fact, basements are notoriously dark and damp places. Yet however common it may be, moisture in your basement can be bad news. Unfortunately for homeowners, a little bit of moisture can turn into a big problem. From structural damage to toxic mold that is hazardous to your health, basement moisture can cause major issues for your home. So what exactly are the causes of basement moisture? And more importantly, what can you do to fix it?

Let’s start at the beginning. First of all, how do you know if you have moisture in your basement? It is important to be able to identify the warning signs and symptoms. The signs of basement moisture may not be as obvious as a puddle of water on the floor. In fact, there are numerous ways in which moisture can present itself in your basement. Here’s a quick list of a few things to look for:

  • Water Trickling Out of the Walls
  • Saturated Base of Concrete Walls (a ring of dampness)
  • Condensation on the Walls and Floor
  • Stained or Blistering Walls
  • Damp, Humid Air
  • Standing Water on the Floor
  • Deteriorating Carpet or Wood
  • Rotting Columns, Headers, and Joists
  • Odor of Mold or Mildew

If you see any of these signs, you are experiencing moisture in your basement. Now that you know there is moisture, let’s find out where it is coming from.

Basement moisture typically comes from one of 3 sources

Rain or Groundwater

Simply put, this is outside water that makes its way inside. As little as 1 inch of rain can bring 1,250 gallons of water pouring down onto a 2,000 sq. ft. home. Without proper grading, downspouts, and gutters, that water might find its way into your basement.

Interior Moisture Sources

Sometimes the water in our basements originated or was created there. Such sources can include dryers, showers, cooking, humidifiers, and even the moisture from newly-constructed concrete.

Ventilation with Humid, Outside Air

In warmer weather, we often open our basement windows to help ventilate the space. However, when we let humid, outside air into our cool basements, it can condense on the walls and floors.

Now that we know the possible sources of the water, we can determine the cause of the moisture, and ultimately what to do to fix the problem. Check out our list of:

6 common causes of basement moisture and how to fix them

#1. An Interior Water Leak

This may seem like a no-brainer, but you should always check for inside leaks first when trying to identify the cause of moisture in your basement. A water leak can come from numerous places: a shower, a sink, a toilet, a washing machine, a dishwasher, a bad pipe, just to name a few. Sometimes, if the moisture in your basement is located on the ceiling or walls beneath a bathroom or kitchen, an interior water leak is to blame. Find where the moisture is located and determine if something in that area is leaking.

How to Fix It: An interior leak is typically one of the easiest problems to solve. Simply repair the leak (or have a plumber take care of it for you) and with any luck, that was the cause of the moisture, and it will be gone for good.

#2. Ineffective Grading

Rain or groundwater often makes its way into basements due to poor grading. The ground around your foundation should slope away from the house, not towards it. If draining in the wrong direction, water will accumulate against your foundation and eventually make its way inside. This often happens when fill dirt around your foundation isn’t properly compacted. As the dirt settles, the slope changes and water flows toward your house rather than away from it.

How to Fix It: Build up the dirt around your foundation, creating a slope aiming away from the house. This should be a minimum of one inch per foot, for at least 6 feet.

#3. Missing or Defective Gutters and Downspouts

The purpose of gutters and downspouts is to direct rainwater away from the foundation of your home. If those gutters and downspouts are missing, or not functioning properly, rainwater is often directed towards your foundation. As water drains toward your house, it can accumulate in the soil around it. If water accumulates around your foundation, chances are, it will make its way inside into your basement.

How to Fix It: Consider adding gutters if there are none already in place. A minimum of 1 downspout should be placed per every 50 ft. of the roof eave. Extenders should be placed on all downspouts, dispersing water at least 4 ft. away from the foundation. Existing gutters should be cleaned regularly to ensure they are functioning properly.

#4. Cracks in Your Foundation

If you have cracks in your foundation, you can be sure that water will find them and make its way into your basement. In fact, sometimes the water is even the cause of the cracks themselves. If floor joists are not properly connected to the foundation walls, it can allow the walls to move, and in turn, cracks are formed. Water can actually cause cracks in the foundation as well due to poor drainage in the soil.

If water is not directed away from your foundation and accumulates against the foundation walls, and that pressure (hydrostatic pressure) can force the water into the walls, creating cracks. No matter how the cracks formed, if they exist, water can enter your basement through them.

How To Fix It: Depending on the cause of the cracks, your solutions will vary. If hydrostatic pressure (due to water accumulating around the foundation) is the cause of the cracks, repairing your exterior drainage should help to solve the problem. The cracks will still need to be repaired, but the cause should have been repaired. If structural problems caused the cracks, proper footing and connections (straps or anchor bolts) should be put into place to seal the gaps. Click here to learn more about ways to fix cracks in your foundation.

#5. Poor (or Missing) Drain Tile and Sump Pit

Many houses do not have a subsurface drainage system. Basements in older homes often were not intended to be habitable spaces, thus an under-the-floor drainage system wasn’t necessary. More modern homes that do have a drainage system often experience problems with their system. This can range from a clogged pipe, broken connection, or a broken sump pump.

How To Fix It: Unfortunately, problems with your subsurface drainage system, or adding one where there wasn’t one, are a much more serious project than some of the aforementioned solutions. If you think this is where your problem lies, its best to call in the professionals. It involves digging up your flooring and adding a drain system, which leads to a pump that will expel any moisture. Building, or repairing a subsurface drainage system is a complex task, best left to experts with tools and knowledge to get the job done right the first time. Click here to get help with your drainage problems.

#6. Condensation

Basement condensation occurs when warm, moist air comes in contact with your cool basement walls and floor. As the walls cool the warm air, moisture is created, just like condensation on a cold beer on a hot summer day. You’re in luck if the moisture in your basement is coming from condensation, rather than a leak or drainage problem, as these issues are typically much easier and less expensive to resolve.

How To Fix It: There are a few ways to deal with condensation in your basement. First off, check the exhaust of your dryer and drain the central air conditioner. Ensure they are not clogged and are flowing properly. Both can cause a surprising amount of moisture to be put into the air. Next, consider one of the following options:

Basement Exhaust Fan: If you have a bathroom or kitchen in your basement, be sure to install (and use) an exhaust fan. Steam from hot showers and cooking creates lots of moisture than if trapped, can create condensation. Be sure to use the exhaust fan anytime a shower is taken or the stove is used.

Increase Air Circulation: If you only have a minor amount of condensation, increasing your air circulation could resolve the issue. If your basement does not have air conditioning vents, consider adding some. It is typically a relatively easy project. Make sure to keep vents open to keep air flowing. If you don’t have AC, adding a fan, and running it a few hours a day, can help to distribute moisture. If your basement is cluttered, eliminating some of the junk will help air to flow more freely as well.

Insulate Your Basement: Insulating the places where condensation builds up can also help to eliminate moisture. Covering those places, such as walls, pipes, and ducts, with insulation, will help keep warm air from coming in contact with the cool surfaces, thus preventing condensation.

Moisture Warning Signs

If you see signs of moisture in your basement, do not wait to do something about it. The longer the problem persists, the bigger and more costly the repairs will be. For more tips or help with your wet basement, reach out to our team at Triad Basement Waterproofing.