To keep your house on its foundation during an earthquake.

1. Lay out bolt locations. For the typical one-story house, use 1/2" diameter bolts at 6 feet on center.

2. Drill holes through existing sill into the concrete foundation for 8-1/2" long expansion bolts, using carbide drill bits.

3. Use right angle drill for tight access places where the crawl space is low.

4. Blow all the dust out of the drilled holes using a rubber tube. Wear goggles and dust mask or respirator for protection from dust and debris.

5. Insert expansion bolts with the washer and nut attached. Leave nut at top of bolt when tapping the bolt in place to protect the threads.

6. After tapping bolt in place, tighten the bolt by turning the nut. Do not over tighten or bolt will be damaged.

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