The Causes of Foundation Structural Problems

Cracked Walls

Wall cracks can be caused by a number of factors. The most common cracks are caused by expansion and contraction of the masonry materials as a result of temperature changes. More extreme foundation cracks are caused by one or more of the problems listed below.

Bowing/ Cracked Walls

As soil around the basement foundation walls becomes saturated with water, it swells or expands. The expanding soil puts pressure against the foundation walls and they can begin to move inward.

Concrete or tile block walls will begin to crack at the weakest point which is usually at the midpoint of the wall between the top and bottom. The crack will appear as a horizontal crack across the wall as the interior side of the wall expands inward. The more the bow inward, the wider the crack will be. At a certain point, step cracking will begin to appear on the adjacent walls at the corners.

Poured concrete walls are stronger. Rather than bowing inward at the midpoint, these types of foundation walls will move inward at the top where the wall and sill plate meet, and cracks will form on adjacent walls from the bottom diagonally to the top.

Foundation Settlement

Foundation settlement occurs as a result of changing soil conditions. There are 3 ways that soils can change under a basement foundation. First, soils can dry out and shrink. The shrinking soil creates cracks or gaps—spaces that allow the foundation to settle into. Second, soils can soften when saturated with water. As the soil becomes soft, the foundation can sink into it. Third, foundations are often built on or partially on fill—soil that has been moved from higher ground, to fill into low areas to make the site level. Parts of the foundation that sit on top of the fill area can settle into the less dense soil.

Slab Settlement

Slab foundations can settle and crack as a result of soil that has shrunk under the slab, as in the case where heat from an HVAC system has heated and dried the soil. They can settle as a result of soil that has been washed out from under the slab, possibly from leaking plumbing of some kind. Finally, slabs can settle as a result of being built on soil that has been improperly compacted prior to building the slab foundation.

Crawl Space Settlement

The first floors of homes built on crawl spaces can settle as a result of one or more of three problems. Some crawl spaces are improperly built to begin with. The columns that hold the beams and joists that the first floor was built on, can be spaced too far apart, allowing the wooden joists and beams to sag. Sometimes, especially in the case of crawl spaces with dirt floors, the beams and joists can become saturated with moisture creating mold and dry rot conditions that allow them to sag around the columns, or at other weak points. If the columns or bracing supporting the beams and joists are constructed or assembled on solid soil, they can settle into the soil, an d allow the beams and joists above to sag or settle downward.

Foundation Structural Problems can be classified into 3 stages

The first stage is characterized by cracks. Forces acting on the foundation cause the masonry materials to crack either from pressure pushing against them or from the weight of the foundation beginning to settle downward.

The second stage is characterized by movement. The forces acting on the foundation have begun to create movement. The walls are moving inward, or the foundation has settled downward. Stage 2 is also where damages to the home begin to occur. Windows and doors stick, or don’t work at all. Beams and floor joists move creating problems with the floors above. Cracking occurs in the walls, ceilings and floor above the foundation. Exterior masonry facings can crack, or worse, begin to fall off the home.

The third stage is failure. The walls and/or floors of the foundation need to be completely rebuilt. The real problem when the foundation is allowed to progress to stages 2 and 3, is that not is there the cost of repairing the damage, but there is still the cost of solving the problem, which has to do with stabilization, so that the problem does not re-occur. This means having to pay twice!

Best Cellar Basement Systems is a full service company, which means that we do much more than waterproofing for wet basement issues and foundation repair.

We are Ohio basement remodeling and Michigan basement remodeling experts!

Call us today to learn more about best basement repair practices.