How to repair hot water cylinder insulation

Making sure that your hot water cylinder is properly insulated is a simple and effective way of saving energy and money. Learn how to repair the insulation on your hot water cylinder with this guide.

Level of difficulty

Level 2: Intermediate

What you need

  • Goggles
  • Dust mask
  • Gloves
  • Insulation blanket
  • Foil, fiberglass, or tubular-sleeve insulation
  • Acrylic tape
  • Impaling pins
  • Staples
  • Staple gun

The steps to follow

Note:
Make sure you wear your safety goggles, gloves, and mask prior to repairing the insulation.

  1. Turn off your hot water cylinder and let it cool off before insulating any of its pipes and the cylinder itself.
  2. Find the spot that needs repairing on the hot water insulation cover.
  3. Using a tape measure, measure the section that needs to be replaced.
  4. With this measurement, cut a piece of insulation the same size.
  5. Place the insulation on top of the damaged section and secure with a staple gun or impaling pins.
  6. Insert tar paper to fill in the gaps between the overlapping insulation.
  7. Tape over the replaced section with acrylic adhesive tape.

To replace the hot water cylinder insulation

  1. Measure the height and circumference of the hot water cylinder.
  2. Buy an insulation jacket based according to this measurement. A hot water cylinder insulation jacket can be purchased from your local DIY store.

    Note:
    Make sure you buy an insulation jacket that is marked with the British Standard Kite mark. Your new insulation jacket should be at least 75mm thick.
     
  3. Fit the insulation blanket around the hot water cylinder. Make sure it is cooled off before you start this step.
  4. Wrap strings around the blanket to secure it to the hot water cylinder.
  5. Make sure the edges are butted together.

Lagging (or insulating) pipes

  1. Measure the pipes that you plan to insulate.
  2. Purchase insulation tubes from your local DIY store.
  3. Cut the tubes to the desired size. You can also cut small split edges at for bends in the pipe to ensure the insulation wraps around effectively.
  4. Fit the tubes around the pipe.
  5. Secure the insulation with acrylic adhesive tape.

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