In this article, we look at hot water tank insulation. We’ll explain why you should insulate your hot water tank and how you can insulate it yourself. Plus, we’ll look at the costs and savings involved in insulating your tank, along with the ideal amount of insulation.
Why insulate your hot water tank?
A poorly insulated hot water tank will lose its heat quickly, so you'll have to use more energy to make more hot water. As hot water is something you need all year round, insulating your tank can save you money even in summer. Fitting a hot water cylinder jacket is usually simple to do and probably all you need. Adding a jacket to an un-insulated tank could save you up to £80 a year1.
What materials are used for water cylinder insulation?
Modern hot water cylinders often have insulation already in the form of hardened foam, and this is usually enough to keep them well insulated. But older tanks may need extra insulation. The modern standard for insulation is 80mm. If your tank has less insulation than this, it’s a good idea to ‘top up’. You can do this yourself by fitting a hot water tank jacket, which you can find in many DIY shops. Just make sure you measure the size of your tank so you know what size water cylinder jacket to get.