Types of Foundation Cracks
Foundation cracks can be quite scary. If you’re showing homes, you might see some cracks that concern you. If you own a home, you don’t want to worry that your foundation is going to fail. For most of us, serious foundation issues are quite rare (unless you live in Brandermill). Here is a general overview of the types of cracks you might find around your foundation or house.
Hairline Vertical Foundation Cracks
All houses settle and crack. These settlement cracks are usually vertical, or near vertical, and very thin, hence the term hairline. You generally don’t need to worry about them. Keep an eye on them. Maybe have them patched to stop moisture, and monitor them for recracking. Basically, don’t lose any sleep over these.
2. Shrinkage Cracks
There is a saying. Concrete has two properties. It is crack and it cracks. Concrete shrinkage cracks look similar to settlement cracks, and are equally inconsequential. The biggest indicator that you’re looking at a concrete shrinkage crack is that it is not continuous. Check out the example below.
3. Differential Settlement Cracks, or Step Cracking
Now we are getting into some more serious cracking. The light cracking in our foundation and drywall is normal. Differential settlement cracks occur when, you guessed it, there is a different in the rate at which two or more areas of the house are settling. This causes step cracking, or diagonal cracking. These cracks are more likely to need professional repair, especially if they are larger than 1/8th of an inch. You will need to have a foundation repair specialist evaluate the soil and the cracks to determine what, if any repairs are needed.
4. Horizontal Foundation Cracks
Alright. These are bad news bears. Horizontal cracks almost always mean you are going to need expensive foundation repairs. Horizontal cracks are caused by excessive pressure from the exterior which is typically caused by water (hydrostatic pressure).
5. Lintel Failure Cracks
I put these into their own category because they are super common here in Richmond, they make some home buyers worried, and they are almost repaired improperly. These cracks emanate outwards from the corner of a window, or door in brick siding. They occur when the lintel fails, starts sagging, or expanding, and put pressure on the surrounding the brick. The proper repair for these cracks is total removal and replacement of the lintel. If the brick is only repointed, the cracking will continue and worsen.