The many different threats of foundation damage we’ve discussed above can manifest in various signs throughout your foundation and living space. We’ll discuss the most common symptoms Louisville homeowners identify below.
Foundation Cracks
Foundation cracks can mean anything from natural, harmless settling to severe structural damage. It will be most helpful to break down the types of cracks by location and size.
Hairline Floor Cracks
Thin cracks form in the basement or crawlspace floor of most homes due to the concrete settling after being poured. They typically don’t indicate structural damage unless they grow in width or are unlevel from one side to the other.
Most homeowners in Louisville have a foundation repair contractor seal these cracks to stop water from getting inside, which is a prevalent issue because of erosion and heavy rainfall.
Vertical Wall Cracks
Like hairline floor cracks, thin vertical cracks on your concrete block wall often form as a result of settling and shouldn’t cause significant concern. You can have them sealed to limit your risk of water intrusion, but they generally don’t require any further repair. However, if they grow to more than ⅛” wide, they may need reinforcement to prevent further expansion.

Horizontal Wall Cracks
Cracks running horizontally along your wall are a result of hydrostatic pressure. Stress on the outside of your foundation wall can build either because of heavy rainfall or water pooling in voids in eroded areas. The pressure can crack your concrete and force the upper wall portion inward.
This type of foundation damage is common in Louisville if your soil has suffered erosion immediately around your home. It signifies structural damage and should be stabilized immediately.
Stair-Step Cracks
Cracks in the shape of stair steps on your crawlspace or basement wall are a result of differential settling. If a portion of your foundation loses support from underneath because of soil erosion, it can sink into the earth until it finds support. Unable to hold the falling concrete, the wall cracks along the weakened block seams in a step pattern.
Stair-step cracks are some of the most dangerous, as they indicate severe structural damage. They should be addressed by a foundation repair expert as quickly as possible.
Moist or Wet Basement or Crawlspace
Moisture or water under your home are both excellent indicators of foundation problems. Liquid water can enter your crawlspace or basement through foundation cracks, and water vapor can seep in through the pores in the concrete, increasing the humidity.
If you have a water or moisture issue, you may notice wet spots of concrete, water visibly trickling in through fissures, water pooling on the floor, or heavy, damp air in the space under your house. You might also find efflorescence on the walls, which is a powdery white deposit of minerals left behind by evaporating water.
Moisture under your home can leave the space prone to mold growth, so visible mold spores or musty odors in your basement can point to foundation issues.
Lastly, moisture naturally attracts rodents and insects, so a pest infestation can indicate that you have moisture build-up and are at risk of associated damage.
Crumbling Foundation Walls
Louisville’s acidic soil is corrosive and gradually decays your concrete foundation, compromising its rigidity and strength over time. You may notice crumbling or flaking on your foundation walls, and you might eventually be able to pull pieces of concrete off with your fingers. The weakening often begins outside your home, where the soil contacts the concrete directly, but the damage will slowly work its way inward.
Crumbling foundation walls can indicate very severe structural damage and should be taken very seriously.
Poor Indoor Air Quality
Lastly, poor indoor air quality can indicate that you have an issue with your foundation. The air under your home integrates into your living space via the stack effect. Moist basement air can increase the humidity in your upper floors, often leading to uncomfortable perceived temperatures and high utility bills.
Additionally, mold spores thriving in a moist basement can enter your living space and create allergic reactions for you or your family members. Symptoms include itchy eyes, sneezing, and difficulty breathing, all of which could indicate you have an issue in your basement or crawlspace.