Dear Angie: What should I do about a basement floor that is cracked? — Susan A., Avon Lake, Ohio.
Dear Susan: Your course of action depends on the size of the cracks and their frequency, among other factors.
Our researchers found that smaller cracks are not unusual, especially as a house settles over time. An average-size basement crack might range in width from a sixteenth to an eighth of an inch.
There are several reasons why a basement floor might develop cracks. Concrete can shrink as it cures. Also, cracks might occur if a house drops below or rises above the original construction level. When soil is extra dry, for example, the floor might sink a bit because its weight is not supported as well as before. If soil becomes over-saturated, it might heave, lifting the floor.
Cracks that enlarge over time, or are followed by other fissures, might indicate a more serious foundation problem. Cracks are a cause for concern if they allow water, radon or methane to infiltrate your home.
Your best bet is to ask a highly rated basement contractor to check your basement floor. Many will provide an inspection for free.
Minor repairs might cost $300 to $500 and might include sealing individual cracks with a flexible material that accommodates floor-flexing over time. More complex solutions can cost thousands of dollars.
It's important to get estimates from several basement companies and to be sure the company you hire has a good reputation and is appropriately licensed, insured and bonded. Avoid any company that uses high-pressure or scare tactics.