What Causes Crawl Space Problems?

Settling Due to Weak Foundation Soils

Settling of columns in a crawl space is most often caused by weak foundation soils. The soil under a home is comprised of multiple soil types and layers, and over time, these soils can shift and settle with changes in moisture content and density.

This movement can cause shifting in the existing columns and the beams above, resulting in foundation cracks, uneven floors and other structural damage within a home.

Improper Spacing of Existing Pier Columns

Another common cause for foundation problems in a crawl space is improper spacing of pier columns. When a home is constructed, pier columns are installed throughout the crawl space to support the weight of the floors above. Pier columns that are spaced too far apart can result in overloaded beams, causing them to bend and sag. When beams begin to bend, the floors above begin to slope, causing cracks to form and many other cosmetic issues throughout the home.

Excess Moisture and Wood Rot

Crawl spaces are notoriously damp and humid spaces and are susceptible to excess moisture and dampness which makes a crawl space the perfect environment for mold to grow and wood rot.

According to the University of Illinois Small Homes Council, as much as 18 gallons of water per day can evaporate into a crawl space under a 1000-sq.-ft, house. Even if your dirt crawl space seems dry and dusty, the soil may be pulling in moisture that can rot wood floor joist and can cause beams and joists to weaken.