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IBA Crew installing Basement Waterproofing

Causes of Leaking Basement Floors

For many homeowners, their unfinished basement isn’t usually the most inviting part of their property; but it should still receive routine maintenance to ensure no problems occur. Some common problem signs include pooling water on the basement floor, water seeping through cracks in the wall or through floor joists, and high moisture and humidity levels within your home.
It’s incredibly important to understand the potential causes of this phenomenon, as well as being able to spot the other signs of damage that often accompany it. Noticing the signs quickly and acting accordingly can be the difference between cosmetic repairs and needing serious structural work on your home. 

Flooded Basement Interior

What Can Cause Leaking Basement Floors

A wet or leaking basement floor can be caused by several issues, some of which are more serious than others. Issues commonly found in homes are: 

Water Seepage 

Water seepage is a mostly benign by-product that occurs because of the porous nature of concrete as a construction material. Seepage occurs when moisture, usually from the soil underneath or around the property, begins to leak through the concrete and into the home. 
You will be able to notice seepage not just by the condensation and humidity, but because of a process called efflorescence. Efflorescence is not harmful, but very noticeable and involves the formation of a white, powdery substance of affected surfaces. This residue is simply the minerals left behind when the water evaporates. 

Excessive Hydrostatic Pressure 

Hydrostatic pressure is, essentially, the weight of water in the soil around a property. Expansive soils, such as clay or silt loam, can exert huge amounts of hydrostatic pressure because of their incredibly absorbent nature. These water-reactive soils can increase in volume when they are saturated, which in turn puts pressure on your property.
The weight of the water in the soil will exacerbate processes like seepage. This pressure and weight can also lead to more serious issues like bowing walls or, when there is a snap freeze, foundation heave. This can cause cracks in a property’s foundation and basement floor, which will let even more water in. 

Foundation Damage 

Foundation damage of any kind can cause your basement floor to leak in water in surprising amounts. Overall, there are three kinds of foundation damage you should worry about. These are subsidence, settlement, and foundation heave. Subsidence and settlement are both processes of sinking that are caused by unstable soil and can make a foundation crack as the weight of a structure is unevenly distributed. 
Foundation heave, by contrast, is a process of upward bulging that causes cracks in a property’s foundation and basement flooring via upwards pressure. In any case, cracks in your property’s foundation and basement floor will act as channels for water to enter your home. 


Even if your basement floor is completely undamaged, it can still end up damp. The most likely cause of this is condensation caused by excessive relative humidity in your basement. The cool concrete surface of your basement floor can gather moisture in the same way that glass and metal will. A professional can help you figure out the cause of any dampness, wetness, or condensation in your basement.  

Other Problem Signs to Watch For 

If you notice any of the following warning signs throughout your home, your basement might be experiencing leaking. It is imperative to call in an expert for an inspection to find out the root cause of the issues.

Musty Smells 

A damp, humid basement that has mold formations is incredibly likely to start smelling musty over time. The smell that is created by mold formations is highly recognizable and will infect your entire home over time. If you have tried cleaning and airing out your property, but the smell simply will not go away, you should look for signs of mold. 
You will recognize these as discolored, slightly furry formations in certain corners of your home. Check behind shelving and cupboards or in the corners of the room. The other possible cause of a bad smell is pest infestation, but these too can be connected to the dampness in the space. Look for signs of infestation, like droppings, nest formations, and live pests, to determine whether pests may be a part of the problem in your damp basement. 

Pooling Water 

Pools of water in your basement are a very strong sign that your floor is leaking or damaged in some way. The placement and size of the pools of standing water can be indicative of the cause and severity of the issue. For example, water in the corners of the room may be a sign of interior leaks or seepage. 
If the pools of water in your basement are in the middle of the room and concentrated around cracks, damage to your property’s foundation and basement flooring likely are to blame. You will also notice that the pool of water may grow if the soil around your home is incredibly saturated. If you can see moving water or visible drips, this is a sign that the pooling water in your home is the result of a plumbing or appliance leak. 

Spreading Cracks 

Spreading cracks are a strong sign of ongoing structural issues in your home. These differ from hairline cracks in that they are big enough to fit a credit card into and they are actively growing. In short, these are a sign that your property is struggling to cope with pressure and strain of some kind. These cracks can indicate a lot, from foundation damage to excessive hydrostatic pressure. 

Uneven Walls 

Uneven walls in a basement with a leaking basement floor are another strong sign that your property may be struggling with excessive strain or hydrostatic pressure from the soil around it. Bowing walls or leaning walls can be incredibly damaging and difficult to deal with. If you notice a visible lean or unevenness to your basement walls, it’s time for you to contact a professional. 
The most common solutions for a bowing or leaning wall in a property’s basement are wall anchors, wall beams, or carbon fiber reinforcement straps. Each of these has different strengths and weaknesses, but all will prevent further deviation.

Sunken Concrete Slabs 

A sunken concrete slab in your basement is a strong sign of foundation damage, especially if your basement floor is also leaking. The issue most likely to cause this is settlement, whereby sections of a property’s foundation sink into voids in the ground that can be caused by shrinking or loose soil. Over time, the slabs above will be affected. 
Struggling to deal with their own weight and the weight of the structure, the concrete slabs that make up the basement floor can start to crack and sink. This is a complex issue to fix, but there are concrete lifting services that can help. 

Leaking Basement Floor Repair is Near You with Innovative Basement Authority

If you see any of these warning signs alongside a wet or leaking basement floor in your property, call our team of experts at Innovative Basement Authority to come out for a free inspection. On the day of, we’ll evaluate your property from any problem signs, while giving you a free quote for our tailored solutions.

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Innovative Basement Authority Service Map

We service Minnesota, North Dakota, South Dakota and Eastern Montana for basement waterproofing and crawl space repair.

Fargo, ND

1330 41st St. N
Fargo, ND 58102

Minneapolis, MN

6265 Carmen Ave.
Inver Grove Heights, MN 55076

Rush City, MN

1325 S Frandsen Ave
Rush City, MN 55069

Sioux Falls, SD

101 S. Reid Street, Suite 307
Sioux Falls, SD 57103