Disaster Preparedness > Strapping Requirements for Water Heaters

Since the City of Los Angeles is in Seismic Zone 4, perforated iron strap
(plumber’s tape) will not be an acceptable method for strapping or bracing
water heaters over 40 gallons. Water heaters over 40 gallons shall have Office
of the State Architect approved straps, and shall be installed according to the
manufacturer’s installation instructions.

The State of California requires that all water heaters be strapped to resist
motion during an earthquake. This may be accomplished by installing an over-
the-counter "water heater restraint" kit which has been designed specifically for
this purpose, and which has been accepted by the California Division of the
State Architect (DSA). Such kits are available from plumbing hardware supplier.
An Alternative method is shown below in Example 2, using heavy-duty metal
strap material and hardware.

As per 1996 LAPC, Section 94.510.5, water heaters must be strapped in at
least two locations, one being in the upper one-third of the unit, and the other in
the lower one-third. The lower strap must be a minimum of 4" above the water
heater control unit.

Example 1 (side-to-side straps).

Drill pilot holes on centerline of stud (both sides of heater), insert screws
through punched holes in strap. Use washers.

Stand required in garage locations as per sec. 94.510.1 LARC..

Example 2 (wrap-around straps):

Drill pilot holes on centerline of stud (both sides of heater), insert screws
through punched holes in strap. Use washers.

Use minimum 22 Gauge X 3/4" wide metal strap.

Stand required in garage locations as per sec. 94.510.1 LA.P.C.

The installation must satisfy the water heater manufacturer’s minimum
clearance requirements, as stated on the unit nameplate.

Lag screws not less than 1/4" in diameter must be used to anchor the
restraints to the wall, and each lag screw must have at least 1-1/2" thread
penetration into a wall stud. A large flat washer must be installed between each
lag screw and the strap for reinforcement.

Water heaters generating a glow, spark or flame capable of igniting flammable
vapors may be installed in a garage, provided the pilots, burner or heating
elements and switches are at least eighteen inches above the floor level.

All over-the-counter kits must be installed according to the manufacturer’s
instruction, and must also meet the conditions above.

Water Heater Straps