Install foundation bolting, cripple wall
bracing, and reinforce chimneys in your home and business.
The houses must meet certain criteria, including being built on a level or low-slope site, on a raised foundation, and with a four-foot (or less) cripple wall
under the first floor.
It flooded shore towns and threatened to cripple Wall
Street and New York City's subway system with a huge surge of corrosive seawater.
In cases where a house's floor joists sit on the sill or where the cripple wall
is very short, you can use 1/4-inch structural steel angle instead of anchor bolts (see photograph below left).
Bracing the inside of your home's cripple wall
-- the short wood-stud wall between the top of the foundation and the first floor -- with sheathing.
specializes in foundation bolting and the bracing of cripple walls
(short stud walls between the floor and foundation of some houses) by using structural-grade plywood which, if needed, provides greater resistance to earthquakes.
These provide guidance on use of cost-effective, "do-it-yourself" mitigation techniques--bolting structures to their foundations and reinforcing cripple walls
These weaknesses include a home that isn't anchored to its foundation, unbraced water heaters, weak cripple walls
, homes built on pier and post foundations, unreinforced masonry foundations, or steep hillsides; and homes with unreinforced masonry walls or rooms over garages.
The California Earthquake Authority is working with the Applied Technology Council to develop retrofit guidelines for houses requiring seismic retrofits not covered by existing guidelines, including "soft story" buildings (typically with living space over a garage), houses on hillsides, and houses with cripple walls
higher than four feet.
As many as 2,000 homes in the city built before 1940 may be in need of seismic strengthening - such as the bolting of the home to its foundation or the installation of plywood sheeting to strengthen homes with cripple walls
are the short framed walls that extend from the top of the foundation to the base of the floor structure.
Other actions listed include underpinning, and bracing of cripple walls