Plumbing

A good starting point is the hot-water cylinder. An 80mm (3in) thick insulating jacket (BS 5615) is cheap, will pay for itself in a year and is easy to fit - you just strap it to the cylinder (4). If the cylinder already has a thin jacket, then simply place the thicker one over the top.

Insulating hot-water pipes will reduce the waiting time for hot water to flow from a tap. The most important pipes to lag are under the floor and in the loft. Insulate the pipe running from the boiler to the hot-water cylinder too.

You must also insulate cold-water pipes in the loft, the cold-water cistern and the small feed and expansion tank (if there is one). The cistern can be wrapped in a purpose-made jacket or lagged with a glass-fibre blanket (5).

All pipework can be lagged with split foam tubes which simply slip around the pipes. Use a double thickness at bends where freeze-ups are most likely. Tape or clip the tubes at intervals to keep them closed (6).

The stopcock is often left unprotected but covers are available and can be fitted in minutes.

If you insulate the loft floor, don't cover the area below the cistern - any heat rising from the room below will help prevent the tank freezing.