A basement with structural damage can present a serious safety risk to your home and those living in it. It’s therefore important to know how to recognize and address several threats to your basement’s structural integrity.

Basement walls can be affected by water infiltration, age, wear, soil conditions, freeze-thaw cycles, mold, and mildew. Some ways to protect your basement include using a dehumidifier, insulating the walls, installing a waterproofing membrane to the foundation, and regularly checking for damages.

Let’s look at some of the most common issues that your basement walls might encounter. We’ll also explore how to address such issues and mitigate the risks where possible.

6 possible Causes of a crumbling basement wall

There are several potential situations that might increase the risk of a basement wall crumbling. Those include the following:

1. Water Infiltration and Oxidation

If water can seep into the basement, it may weaken the structural integrity of the walls over time and cause oxidation. Water infiltration can result from poor drainage, cracks in the foundation, or a high water table.

There are several steps you can take to prevent water infiltration and oxidation in your basement walls:

• Ensure your gutters and downspouts are in good condition, directing water away from your foundation.
• Check for any cracks or holes in your foundation and repair them. Seal any gaps around pipes or wires that enter the basement.
• Install a sump pump (on Amazon) if you have a high water table or if water accumulates in your basement.
• Consider installing a French drain or another drainage system around the perimeter of your foundation to help keep water away from the walls.
• Keep your basement dry using a dehumidifier (on Amazon) or a fan to circulate air.
• Ensure your landscaping slopes away from your foundation so that water drains away from your house.
• Regularly check your basement walls and floor for signs of water infiltration.
• Consider installing a waterproofing membrane (on Amazon) to your foundation walls. You can do this internally or externally.
• Rust inhibitors (on Amazon) can be applied to metal surfaces in your basement to prevent rust from forming.

It’s important to address any water infiltration or oxidation issues as soon as possible. Doing so will help prevent further damage to your foundation and basement walls.

2. Age and Wear 

Basement walls are subject to pressure from the soil and the house weight above. Over time, this pressure can cause the walls to weaken and crumble.

Preventing the pressure from damaging basement walls can be challenging since it’s a natural process that occurs over time. However, there are several steps you can take to reduce the risk of damage:

• Regularly inspect your basement walls for signs of cracking or shifting. If you notice any issues, address them as soon as possible.
• Ensure your foundation is properly supported by ensuring that the soil around your foundation is compacted and has proper drainage.
• Add reinforcement to your basement walls to help support the weight of the house and reduce the risk of cracking.
• Keep the humidity levels low in your basement to reduce the risk of moisture-related damage.
• Avoid using the basement to store heavy items that could put extra pressure on the walls.
• Have a structural engineer inspect your foundation and basement walls to ensure they’re in good condition and identify potential issues.
• Regularly maintain your foundation and walls. That includes repainting, cleaning, and repairing as necessary.
• If you’re planning to remodel or make changes to your home, consult a professional to ensure that the work won’t compromise the structural integrity of your basement walls.

It’s important to remember that age and wear can speed up due to other factors such as water infiltration, poor construction, or soil conditions. 

3. Poor Construction

If the basement walls were not constructed properly, they might be more prone to crumbling. 

Poor construction may have included the use of substandard materials, violations of building codes, or insufficient reinforcement of the walls.

If you suspect your basement walls were poorly constructed, addressing the issue immediately is important to prevent further damage. Here are the steps you can take:

• Consult a structural engineer or a qualified contractor to assess the condition of your basement walls and determine the extent of the poor construction. They’ll be able to recommend the appropriate course of action.
• If the damage is minor, such as small cracks or holes, the engineer or contractor may recommend patching or reinforcing the walls to strengthen them.
• If the damage is more significant, such as major cracking or shifting, the engineer or contractor may recommend reinforcing the walls with steel beams or carbon fiber straps.
• In some cases, the engineer or contractor may recommend a full or partial replacement of the basement walls.
• If you learn that your basement walls were not constructed per building codes, you must bring them up to code. To do this, you must have them inspected and, if necessary, modified by a qualified contractor to ensure they’re safe and comply with local regulations.
• It’s also important to address any underlying issues that may have contributed to the poor construction, such as poor drainage or a high water table.

It’s essential to keep in mind that addressing poorly constructed basement walls can be a major and costly undertaking. 

4. Soil Conditions 

The type of soil plays a role in the stability of basement walls. The same applies to the condition of the soil.

The right soil conditions for building a basement will depend on several factors, including the type of soil, its moisture content, and the climate. 

In general, the ideal soil conditions for building a basement include:

• Compacted soil with good bearing capacity will provide a stable foundation for a basement.
• The soil should have good drainage to prevent water from accumulating around the foundation and causing damage.
• A low water table is preferred. A high water table can cause water to seep into the basement and damage the walls, so it’s important to have a low water table when building a basement.
• Soil that doesn’t expand and contract excessively with changes in moisture can reduce the risk of foundation cracking and shifting.
• There should be no presence of harmful chemicals or heavy metals in the soil, as they can affect the durability of the foundation.
• There should be no risk of soil liquefaction — a phenomenon that occurs when soil loses strength during an earthquake.

When building a basement, it’s important to conduct soil tests to determine the type and condition of the soil and the water table level. 

If the soil conditions aren’t ideal, a professional engineer can recommend improving the soil or designing a foundation to accommodate the existing conditions.

It’s also important to note that even with ideal soil conditions, foundation, and basement maintenance is essential to keep them in good condition over time.

5. Freeze-Thaw Cycles 

Water entering the basement walls and freezing can cause the walls to expand and crack. Therefore, freeze-thaw cycles can cause significant damage to a basement over time. 

These are the steps you can take to protect your basement from freeze-thaw cycles:

• Keep your basement well insulated to reduce the risk of freezing. Insulate the walls, floors, pipes, or ducts running through the basement.
• Keep the temperature in your basement above freezing at all times, even during the winter. Use a space heater (on Amazon) or a separate heating system if necessary.
• Use a waterproofing membrane for your foundation walls. You can do this internally or externally to prevent water from penetrating the walls.
• Keep your basement dry using a dehumidifier or a fan to circulate air.

6. Mold or Mildew

Mold and mildew can cause significant damage to a basement over time. They can also be a health hazard for you and your family. 

The following steps can help you to stop mold and mildew from growing in your basement:

• Keep your basement dry and fix any leaks or water infiltration issues.
• Insulate your basement and use a waterproofing membrane on your foundation walls. Furthermore, dry up any standing water.
• There are some paints and coatings available that contain mold inhibitors. These can be applied to walls, ceilings, and floors to prevent mold from growing.
• Ensure your basement has proper ventilation to help reduce humidity levels.
• Keep an eye out for signs of mold, such as discoloration, musty odors, or visible growths.
• Address any issues with mold or mildew as soon as possible, both to prevent further damage to your basement and ensure your family’s health and safety. 

If you’re unsure how to address the issue properly, consult a professional, like a mold remediation specialist or waterproofing contractor.

In some cases, they may recommend a full or partial replacement of the basement walls. But, naturally, none of the repair work you do is worthwhile if you do not address the underlying cause.