Page 638 - 2018 National Home Improvement

2018 National Home Improvement Estimator, All Rights Reserved Page 511

Masonry and concrete chimneys usually have a flashed, counter-flashed and caulked construction joint
where the chimney joins the exterior finish. This joint allows the chimney to move independently of the
remainder of the home during an earthquake. Even light ground-shaking can cause this joint to open. If
the flashing is intact, running a new bead of caulk down the open joint will restore weather-resistance.

Repair of damaged masonry chimneys is usually prohibited in seismic zones. The chimney has to be
removed completely and re-built to current code standards. Although the code permits adding a new
metal chimney to an existing firebox, it's usually more practical to replace both the firebox and chimney
with a new prefabricated unit.

Mechanical, Electrical, and Plumbing Systems
The most likely damage to plumbing will be a water heater that's tumbled over or a water heater vent
that's become dislodged. If the water heater remains upright, check the gas and water lines for evidence
of a leak - especially if the connection is made with rigid metal pipe or tube. Proper restraints on the
water heater and flex connections can prevent most earthquake damage.

Duct, flues, piping and electrical lines can rupture when framing is flexed by ground movement. But
there's seldom a need to look for trouble. The problem will usually be obvious: A vent or duct that's
blocked; an electrical circuit that's out; moisture leaking out of a concealed plumbing line; a suspended
light fixture that's hanging by the electrical wire conductors; an appliance (such as a furnace) that's
tumbled over and ruptured the connections. Unless displacement or shifting is obvious, it's usually safe
to assume that plumbing and electrical lines, vents and duct have survived an earthquake intact.

There is one exception. Ground shaking can dislodge deposits that accumulate in water supply lines
and water softeners. If there's a noticeable drop in pressure at a fixture or a water tap, suspect blockage
in the line. Remove the screen filter or valve at the fixture. Then use water pressure to blow out the line.