MGA Construction Company
Foundation Not Anchored
The Problem
When an earthquake moves a house from side to side and up and down, the house can move off
its foundation if it is not anchored. This can cause a fire from broken gas lines, and
damage the foundation, floors, walls, windows, and other utility connections as well as
the contents of the home. It is very expensive to lift a house up, put it back on its
foundation, and repair this damage.
How to Identify It
If the first floor of the house is built off the ground, the area between the first floor
and the ground is called the crawl space. Look in the crawl space for the heads of anchor
bolts that fasten the sill plate-the wood board that sits directly on top of the foundation-securely
to the foundation (see Figure). You should be able to see the large nuts, washers, and anchor
bolts installed every 4 to 6 feet along the sill plate, or bent steel plates, connecting the
foundation to the home.
What Can Be Done
Drill holes through the sill plate and into the foundation and install special bolts,
or install steel plates, connecting the foundation to the sill plate of the home.
Figure - A home's crawl space may be formed by a cripple wall plus foundation or the floor joists
may rest directly on the sill plate, as illustrated here. In either case, you should be able to see
the heads of anchor bolts, installed every 4 to 6 feet, that fasten the sill plate to the foundation.