Diagnosing Cracks in Your Basement and Foundation Walls

Cracks in your foundation and basement walls come in a wide variety of shapes and sizes. When cracks become large enough, water leaks in and makes them bigger over time. This is why it’s important to monitor for cracks. If something (like a cinder block or even an entire wall) is cracked in two, movement and water pressure will continue to make it worse and trying to patch up these more serious cracks usually results in failure.

Monitoring cracks is pretty straightforward. Use a pencil and mark off the ends of the crack with the date. Over time you can see if the crack is just natural settling, or a serious foundation problem. This will also help contractors in repairing your cracks if they can see how they formed.

Cracks will usually form where pipes enter the house, near windows, tie rods, corners where walls meet wall or floor, and in the long open sections of your foundation.

Vertical and Diagonal Cracks – These are typically the result of a concrete foundation settling and can be found in all kinds of homes. Because concrete shrinks when it cures, these natural cracks are called shrinkage cracks. They will usually form in the middle 1/3 of a wall, will be less than 1/8th of an inch wide, and run vertically or diagonally. If the crack extends to the structure (past the basement wall) or is located near a corner (not the middle 1/3), or is larger than 1/8th of an inch, then it is likely not a shrinkage crack and should be checked out by a professional contractor.

Horizontal Cracks – Cracks that run horizontally are a more serious type of crack. They are caused by pressure from the outside of the walls (hydrostatic pressure) and can lead to a failure of your foundation walls. While your foundation is designed to handle this pressure of water and soil, additional load (heavy rain) can put it over the edge and create cracks. Any damage like this to your foundation definitely needs to be check by a professional contractor before it gets worse.

“Bulging” indicates serious hydrostatic pressure and will definitely cause additional cracking. If you ever notice your walls bulging call a contractor immediately because your foundation is at risk of collapse.

Foundation Floor Cracks – If the floor of your basement or foundation is cracking, this indicates a serious problem that can lead to flooding and can even let in radon gas. This is usually caused by soil erosion or swelling around your foundation, or from problems during actual construction. Either way, a professional contractor should be called on to inspect the problem.

For the most part, anything beyond settlement or shrinkage cracks needs attention. They will only get worse and will eventually lead to incredibly expensive problems.

There are a few other things ask when looking out for foundation problems. Are cracks wider at the top then at the bottom? Do the cracks change direction? Do cracks appear on finished walls, plaster, or drywall? Are doors and windows not closing properly? Is it obvious that walls or floors are no longer level?

Answering yes to any of these questions means something more than a shrinkage crack. Call a professional contractor today!