What warning signs are present? How is a cracked foundation identified? How severe is the problem?
Foundation cracks are usually evident on the outside of the home, but are often also identified by drywall cracks above doors and windows inside the home. These cracks can range from minor to severe and can result in the need for extensive foundation stabilization. Cracks can be horizontal, vertical, or stepped — the sizes and orientations of cracks, along with our measurements, identify what kind of movement is taking place. For example, a horizontal crack through a basement wall indicates the wall is bowing into the basement area. In this case, depending on the severity of measured movement it could require a range of solutions from simple preventive maintenance to structural stabilization with steel soldier beams.
What causes foundation to crack? Any underlying factors?
Some causes of foundation cracking include poor drainage management, exterior grade sloped toward the home, exterior grade relatively flat around the home, damaged/obstructed/missing roof gutters, or standing water in the crawlspace. Persistently wet soils around the perimeter of the home can cause footings to settle into the soils at a faster rate than at other relatively drier locations around the home. This difference in settlement rates is called “differential settlement”. Basement walls can crack as pressure builds up on the outside of the wall due to improperly drained soils which are much heavier than properly drained soils. Basement walls that are more than 15 years old may not be reinforced with steel rebar within the wall like modern walls should be. Exterior drains at the base of the wall also tend to clog with fine soils over time. These factors can cause walls to bow or lean inward.
How is a cracked foundation fixed? What methods are used? What are some pluses and minuses of each?
Minor cracks with minimal settlement may often be addressed with proper drainage management or installation of French drains or swales. More serious settlement cracks require installation of deep foundation supports such as helical piers which provide a permanent fix. Minor basement wall cracks may be addressed by installing epoxied carbon-fiber kevlar straps, steel i-beams, or earth anchor tiebacks, depending on the nature and severity of the problem. These are also permanent fixes.
Cost of Inaction
What is the potential cost of inaction (financially, physically)? How does cracked foundation worsen over time?
Failure to address foundation cracks when they are small often requires expensive permanent supports to be installed. Neglected, cracked basement walls can continue to lean and eventually even collapse in worst cases.