I live in Edmond, OK and it seems that at least once a day we have an earthquake. Some are small and others feel much bigger. They are not tearing apart the house but I know they are affecting the house. I am sure many of you have concerns about how do all these earthquakes actually impact your foundation and your house as well.
One of the biggest things you can do is simply be aware. Walk through your house. Take a good amount of time and notice where cracks already are apparent. Take notice of how big the cracks are. There are multiple kinds of cracks and some of them are quite typical, especially in Oklahoma with our clay soil.
In Oklahoma, cracks are common because most houses are built on clay soil. Clay will expand and contract based on the amount of moisture. In really dry seasons, it may be beneficial to even water your foundation. In really wet seasons, it is recommended to take special care to keep water from pooling around the foundation. Below, I talk a little more about drainage.
Shrinkage cracks are fairly common and aren’t always a cause for concern. They are for the most part vertical, quite thin/hairline even and in the middle of the foundation. When the concrete cures (dries) it sometimes cracks from shrinking. If you see the crack moving from the foundation up the wall, this is where you should take more concern.
Cracks caused by the foundation settling are sometimes but not always a concern. Typically when a house is built, it settles into place. This can cause cracking that looks like a step where brick is involved. If you notice one of these cracks and it hasn’t changed since the house was built, it is probably not a concern.
This is why it is important to be able to have some understanding of where the cracks are already as earthquakes pick up. If you see any of the following, I recommend you talking with a structural engineer or qualified contractor to evaluate the potential problem.
- Is the crack bigger than 1/8th inch?
- Has the crack grown recently? Is it longer or wider?
- Does the crack start narrow at one end and get larger at the other end?
While you can’t control earthquakes, take care to control the things you can. Drainage has a major affect on the property. Do you see:
- water pooling around the foundation
- the yard sloping towards the house
- moss or any organic growth on the side of the house
These are indicators that moisture is present. It is recommended that you check with a qualified contractor or irrigation specialist to get rid of the excess moisture.
It is also important to make sure your roof and siding are not letting in excess moisture. Water is the biggest enemy of a structure. Once water gets inside, it starts deteriorating the structure. If you see this, get it checked out by a qualified contractor.
So if you see cracks that are bigger than 1/8th inch, wider at one end than another, have changed than when you first moved in, or are visible on the outside of the house and inside of the house, I recommend checking with a structural engineer. Cracks that are less than 1/8th of an inch are usually not cause for concern.
Next week, I will be writing about what to do when an earthquake does happen.
*While my goal is to help you be an informed home owner, this blog is not an alternative to an actual home inspection by a local inspector. It is also not an assessment of the condition of your house. If you have structural questions, contact a structural engineer or qualified contractor. Construction standards also vary state to state and may be different than where you live. ©2015 – OKC Inspection.