How to Protect Your Water Tank from The Winter Chills

Winter is coming and if you have a water tank then you'll be all too aware of the effect of a freezing cold night. A sustained period of cold weather, including frost and snow, can cause serious problems with your water tank, including cracking in the plastic. This is especially important if you have a tank storing wholesome water (suitable for drinking or cooking), as regulations require it to be protected from frost and extreme heat. Luckily there are now ways to protect your tank from the cold weather, ensuring that your water runs all year around.


The best way to keep a tank safe in cold weather is through insulation. You have a choice between plain GRP or pre-insulated, but personally I prefer and recommend pre-insulated. A pre-insulated tank will have fully encapsulated foam, which will protect it from external issues. By purchasing this kind of tank, your insulation will last longer as it won't be exposed to environments that can help the material degrade (such as direct sunlight), damage from work going on around it, or mice nibbling at it.

An internal tank is likely to be in a warmer environment, so 25mm insulation is suitable as it helps reduce the risk of freezing. However, for a tank that's outside you can go as high as 100mm, with suitability depending on the location and volume of the tank. Insulating your tank can also help with maintaining a steady temperature, which can be essential if you use your tank for chemical storage. The insulation is also HCFC and CFC free, so you don't need to worry about chemicals leaking through the plastic in to the water supply.

If you already have a tank but didn't buy it pre-insulated, then don't panic! An insulation "jacket" can be purchased which will offer the same protection. You can have this installed at the same time as a maintenance check, which I recommend you get to ensure your tank is still doing a good job and can withstand a few more years of wear and tear.

Cover or Lid

Alternatively, if you are concerned that you can't afford insulation, a tank cover can also offer protection from the chilly winter weather. Exposing the surface of water directly to cold air will lower its temperature significantly and increase the risk of it freezing. A simple lid or cover will act as a first layer of insulation, preventing a dangerous drop in temperature. Tank covers also offer extra protection from contamination from rodents, birds, rainwater or leaves (depending on the location of your tank), and provide safety for workers who may be nearby.

If you have a water tank and are concerned about the cold weather, now is the time to look at your insulation needs. Overnight frost or a long-term temperature dip can cause damage to your tank and the contents, and a drain and repair job may take longer and cost more than arranging insulation now. Insulation also offers protection from higher temperatures, so it's suitable for protecting your water all year around.