Water storage and heat appliances

Is your water cylinder and heat pump secured to the walls?


An unrestrained hot water cylinder or heat pump water heater can move and cause a lot of damage during an earthquake either from its mass or from leaking water.

Heat pump water heaters usually stand outside the house against the wall with rigid plumbing into the house.

Some houses use a gas califont to heat water instead of a hot water cylinder.

To check

Around the sides and at the top your hot water cylinder or heat pump water heater, does it have retaining blocks, straps or other means (eg close-fitting shelves around internal cylinders) to prevent it from moving?


You can buy kits from hardware stores that contain the strap, screws and turnbuckle you need to secure your hot water cylinder.

  1. Fit two vertical timber blocks up the full length of the cylinder or heater.
  2. Attach them to the wall frame and make sure they fit snugly between the wall and the cylinder or heater.
  3. Tighten two 25 x 1mm galvanised steel straps around the top and bottom of the cylinder or heater and attach them securely to the wall frame. If the capacity of your cylinder or water heater is more than 200 litres, add a third strap.


  • For outdoor restraints, make sure all straps and fasteners are corrosion resistant.
  • For internal cylinders that can be restrained in a corner:
  1. Nail or screw timber-retaining blocks to the floor or shelf supporting the cylinder.
  2. Glue timber blocks to the walls so they fit snugly between the wall and cylinder at the top and bottom of the cylinder.
  3. Place 8mm screw hooks into your wall frame near the top and on both sides of the cylinder.
  4. Attach a 6mm turnbuckle to one hook and cut a length of 25 x 1mm metal strap so it fits around the cylinder.
  5. Connect the strap to the other hook and use a turnbuckle to make it tight.