As a real estate agent, you’re quite familiar with the types of home foundations present across your territory. You’re also all too familiar with the challenges that can arise due to your local soil and climate conditions when it comes to basements, crawl spaces, slab foundations, and even outdoor concrete driveways and sidewalks.
In our work as foundation repair professionals, we’ve been there and done that throughout the nation. To help with your efforts, we’ve pulled together this guide to identifying home foundation problems and what to do about them.
Foundation Type by Region
To help put things into perspective, this chart shows the foundation types used in new home construction across the four regions of the U.S.
As you can see, the choice of foundation varies quite a bit from a majority of basements in the northeast and midwest to a majority of slab foundations in the south and west. These choices are not necessarily those made by homebuyers but instead are due to local climate, soil conditions, and water levels. For example, 82% of new homes in the south with slab foundations are due primarily to high water levels and soil that isn’t favorable for basement walls.
On the other hand, winter conditions in the northeast and midwest require foundations that are constructed to reach below the frost line. That makes basement construction cost-effective vs. the only other option of using deep pilings for slab or crawl space foundations.
Causes of Foundation Problems
The chart above shows the types of foundations built and those that are most suited to the region’s soil and climate, but that doesn’t necessarily preclude problems from developing over the years. And it certainly doesn’t exempt older homes from foundation problems. These problems can happen anywhere.
These are the most likely causes of foundation problems.
- Foundation settling.
Settling of any type of foundation is normal within the first few years after construction. Over time, many other factors can cause excessive settling, resulting in damage to the foundation.
- Clay bowl effect.
During construction, the soil is excavated, and once the foundation is completed, the backfill soil is replaced around the foundation. That backfill is loose soil near both the foundation walls and the undisturbed soil in the yard. Rain then takes the easy path through the loose soil directly up against the basement or crawl space walls, building up hydrostatic pressure that can cause cracks, allowing water to enter the basement or crawl space.
- Weather extremes.
Even without the clay bowl effect, heavy rain and storms can lead to flooded basements or crawl spaces as well as shifting slab foundations. This is usually caused by drought or dry spells drying out the soil causing shifting and cracks which the heavy rain enters when it finally does arrive. Clay soils can also expand with heavy rain, placing still more stress on the foundation.
- Gutters and downspouts.
One of the best protections against heavy rain is to route it away from the foundation. Gutters collect rain off the roof, guide it to the downspouts, and then out to the properly graded runoff. Clogged gutters and downspouts result in rain pouring directly off the roof and onto the foundation.
- Exterior grading.
Keeping excess water away from the foundation is the job of landscape grading. It needs to be a gentle slope that moves water away rather than allowing it to pool around the foundation. It teams up with the gutters and downspouts. Downspout extensions can be very helpful as well.
- Tree and shrub roots.
If trees and shrubs are planted too close to the foundation, their roots can physically shift the foundation. They can also remove water from the soil during a dry spell or drought resulting in uneven settling of the foundation developing cracks and shifts.
Signs of Foundation Issues
It’s good to have an understanding of the major causes of foundation problems, but the real key is to identify any issues so you can take the appropriate action. Here’s what to look for in the homes you’re buying and selling.
They can appear in the basement or crawl space walls, exterior bricks, interior walls, ceilings, and floors.
- Sagging or uneven floors.
Watch for a slight tilt to the flooring as well as any sagging and sinking.
- Slab leaks.
Water line or sewer line leaks underneath a slab foundation can develop from a shifting foundation.
- Doors and windows.
Doors or windows that stick or don’t close are a sure sign of a foundation issue.
- Cabinet doors.
Kitchen or bathroom cabinet doors that don’t stay closed mean they or the wall is tilting, usually driven by a shifting foundation.
- Chimney and fireplace.
Watch for a leaning chimney as well as leaks and cracks around the fireplace.
- Water in basements.
This is usually caused by cracks and gaps in the basement walls due to excess water, shifting soil, and indicates a foundation under stress.
- Mold and mildew.
This can appear in crawl spaces or basements due to excess moisture and can be caused by foundation issues.
- Rotten wood.
Whether in a crawl space or basement, it’s a sure sign of excess moisture.
Home Foundation Waterproofing and Repair
Foundation repair options vary by the type of foundation and the type of needed repair. Here’s a quick overview.
- Basement waterproofing.
The best approach is to install professional waterproofing with interior drainage and a sump pump with a battery backup. A dehumidifier may also prove helpful in high-humidity climates. It’s also important to make sure the exterior drainage system has properly sized and installed gutters and downspouts as well as landscape grading that moves water away from the foundation.
- Crawl space waterproofing.
Professional crawl space waterproofing and encapsulation will completely address water issues. Sump pumps and dehumidifiers can also substantially reduce moisture and humidity problems. Exterior drainage systems should also be addressed.
- Basement and crawl space foundation repair.
If the basement walls are bowing or bulging, a support system may need to be installed. There may also be a requirement to update supports or walls that have degraded substantially over time. Repair options include wall straightening, wall anchors, and piers.
- Slab foundation repair.
With excess shifting and settling, permanent stabilization with piers is the best way to go for slab foundations. Exterior drainage should also be a part of the broad solution to stabilizing the foundation.
Home Concrete Repair
In addition to foundation problems, soil and climate conditions can be just as disruptive to outdoor driveways, sidewalks, and patios. You’ll see uneven settling and cracks that can become safety hazards.
The best repair option is concrete lifting and stabilization using injections through the concrete that fills any void underneath and stabilizes it. Traditionally, mudjacking has been used, where heavy mud is injected under the concrete. But modern polyurethane foam offers several advantages.
It is lightweight so it doesn’t contribute to the sinking problem. It is waterproof, so it stops any leaks. And only a few penny-size holes are used for the injection process. It is also much more cost-effective than replacing the concrete.
Call on the Experts
If you find any of the signs of foundation or concrete issues, it’s wise to call in the experts to fully assess the situation. They will use their extensive experience and expertise to develop the approach that best fits your property.
That’s where our local foundation professionals can help with a free inspection to determine the exact causes and how best to fix them.