Earthquake Contractor, Foundation Repair, Foundation Contractor
Older houses—those built before 1980—may not be adequately anchored to the foundation, making them more vulnerable to shaking and more likely to slide off their foundation during a quake.
For houses with short (less than full-story height) wood-framed walls between the foundation and the wood-framed first floor—in the crawl space under the house—a retrofit is needed to strengthen this area and make it less vulnerable to shake damage.Both stem wall and crawl space wall (cripple wall) houses may require bolting. Foundation anchor bolts are installed on these walls.
If a house has crawl space walls and bolting, plywood bracing may also be needed to further protect against earthquake damage. The walls are braced by nailing plywood sheathing to the inside of the walls that surround the crawl space.
Water and soil conditions also create permanent foundation problems. Much of California is on clay or expansive type soils. Expansive soils act like a sponge. As they absorb water, they swell, and as they lose water, they shrink. As the soil under a house shrinks and swells with the seasons, the foundation will move up and down. As the foundation moves, damage to the property and/or foundation becomes a problem.
When a property sits on a raised foundation on expansive soil, it experiences continual soil expansion and contraction. This causes normal “settlement” and usually leaves the floors higher in the center of the property.
If an owner wishes to stop seasonal property and foundation damage, a controlled watering program must be instituted. Keeping the moisture content of the soil under the foundation constant, foundation movement can often be stopped. YC Builders assists the property owner by performing a foundation preventive maintenance program.