It is essential for those who live in areas with high earthquake risk to understand the importance of securing their water heater by using strap. During the earthquake event that cause intense tremor, water heater may move heavily, so leaving the equipment without strongly wrapped strap that screwed safely to planks may cause it to fall.
This is the reason why each state in the U.S. has water heater strap code that must be followed. Learn more about water heater strapping below.
Water Heater Strap Code Washington State
As cited from 2018 Washington State Plumbing Code, all water heaters in this state must be strapped or anchored to prevent it from stumbling or collapsing due to the motion of earthquake. The straps must be set at upper 1/3 and lower 1/3 of the water heater’s height. For the lower strapping point, the distance between the strap and the strapping controls shouldn’t be less than 4 inches (102 mm).
Water Heater Strap Code Oregon
According to the Oregon Plumbing Specialty Code regarding water heater strapping requirements, the water heater must be strapped or anchored with plumber’s tape or comparable materials for strapping or anchoring purpose. The strap’s connector must come with washers to make sure that it won’t pull through the straps. Some approved connectors are including 0.25 inch wedge concreter anchor with minimum length of 1.5 inch or #12 x 1.5 inch wood screw.
Water Heater Earthquake Strap Code
The Uniform Plumbing Code has laid out the seismic safety regulations for water heaters by using straps since 1982. The guideline is required to prevent water damage, explosion, or fire in case the water heater unit overturned amidst an earthquake.
Your water heater tank is mostly already strapped, but you need to check if it’s done correctly because it uses the old water heater strap code, which is not recommended anymore. The recommended water heater strapping procedure has been modified, due to the proven ineffectiveness during 1989 Loma Prieta earthquake and 1994 Northridge earthquake events.
Here are the recommended approaches by experts:
- Instead of securing at the middle or the top of the tank, secure it twice at the upper and bottom parts.
- Instead of using plumber’s tape, use heavy-duty metal strapping. A lot of water heater units forced through the plumber’s safe during both earthquakes mentioned above. This was mostly because plumber’s tape uses slim metal that’s apparently too frail to work effectively.
Below are the recommended methods to secure the water heater:
- Create only narrow space between the wall and the water heater unit. You may use wooden plank secured to the wall if the distance is more than an inch or two. This is important to prevent the unit to tip backwards.
- Circle the tank with heavy-duty metal strapping once and a half round. Begin by locating the straps behind the unit’s tank, to the water heater’s front part, then back to the back part near the wall.
- Brace the strap to the wooden plank or to the wall by using lag screws that have oversized washer in the size of 0.25 x 3 inches. In case the unit is secured right to the concrete, the screws can be replaced by 0.25 inch expansion bolts.
- Use flexible connectors for water and natural gas line, instead of metal and copper pipes.
The best way to avoid this unwanted type of accident in the event of disaster is by performing prevention. To prepare your plumbing system, you can buy and install the State Architect-approved strapping kit from hardware store in your area. It is also recommended to have it installed by experienced licensed plumber to ensure that you have followed your state’s water heater strap code.