General Contractors and All They Do

3 Common Cinder Block Foundation Problems

Poured foundations are far more common throughout the country today, but according to industry professionals, about 16 percent of the nation's foundations are made from concrete cinder blocks. Each building method has its own advantages and disadvantages, but some defects are more frequently seen in homes with a cinder block foundation. Here are three common issues to be aware of that may need repair in the future:

1. Improper Construction

Cinder blocks are inexpensive. They are also easy — in theory — for the do-it-yourselfer to work with. After all, you don't need to build forms and have a cement truck come in and pour and settle concrete walls when you use cinder blocks.

Unfortunately, skill is still needed to properly build a home or other structure's foundation with cinder blocks. Cinder blocks are also hollow; most experts recommend that reinforced steel bars as well as cement be poured into these hollow spaces for added strength.

2. Bowing or Collapsed Walls

Both cinder blocks and poured concrete walls can withstand a lot of pressure weighing down on them. Unfortunately, their strength can be compromised when pressure is exerted from the sides. For example, if water is allowed to pool around a foundation and the soil becomes laden with water, that pressure can begin shifting the blocks.

Heavy rains or melting snow loads that are not properly diverted away from the house often lead to this problem. The soil must be graded away from the home and the roof must utilize a drain spout system to carry water away, otherwise problems like this will be likely.

Bowing or collapsed walls can also happen in areas that receive extreme shifts in temperature. If the cinder blocks are not built beginning below the frost line, the heaving and shifting frozen soil will damage the foundation.  

3. Diagonal Cracks

Concrete cinder block walls may develop cracks in between the blocks. These often run diagonal on the wall, with the cracks resembling steps of a staircase. This can occur anywhere on a wall but are most common in the corners. This type of crack is usually indicative of vertical movement in the wall.

Diagonal cracks may occur because the wall may not be settling evenly. For example, the left side of a wall may be settling faster than the right side of the wall, leading to cracks in the corner. Frost heaves and sinkholes from unstable soil types, such as expansive clay, are other possible reasons for diagonal cracks.

Be sure to contact a foundation repair contractor if you notice anything abnormal in your foundation or foundation walls.