Properly lagging both hot and cold water pipes and tanks is an important part of saving energy and money in your home. Lagging pipes which carry hot water helps to keep the water hotter, allowing you to run your water heater at a lower temperature, whilst lagging cold water pipes helps to prevent the pipes freezing and possibly bursting in cold weather.
Pipe insulation comes in two main forms, and which one to use depends very much on when you are applying the lagging. If you are lagging pipes as they are being fitted, it is best to use the felt-like type of lagging which slides over the pipe and is most suitable for pipes being fitted beneath floorboards or a cement screed. This generally comes in a large rolls and is less bulky than the foam lagging.
Foam lagging, usually pre-split along the length, is best for when you need to fit the lagging to pre-existing pipes. Simple cut the foam to length using and sharp knife, open the split and slot it over the length of pipe. Use insulating tape to seal the joints. If you need to fit the lagging to a pipe with a right-angle in it, simply cut each end of two pieces of lagging at an angle to create a mitre joint. Again, seal the joint with insulating tape. To fit foam lagging to a t-joint in your pipework, cut the two pieces for the “arms” of the T into mitres, and cut the piece for the “upright” of the T into a point. The three pieces should then slot together tidily at the T-junction of the pipe.
If you are lagging hot water pipe runs, consider if the heat they radiate is contributing to the warmth of the rooms through which they pass. Lagging for cold water pipes is most important in unheated areas of the home such as attics or garages, where they are more likely to freeze. If you are working on a tight budget, concentrate on these areas first.
Insulating Cold Water Tanks
It is important to insulate cold water tanks as they will be situated in the attic, which is almost always unheated. You can purchase purpose made insulation jackets which are fairly cheap and easy to fit yourself. You can also make your own insulation by placing some roof insulation into large black bags until you have enough to wrap around the tank, remembering to make enough to cover the top as well. Attach your home-made insulation to the tank by wrapping string around it or by using bungee cords.
Lagging the Hot Water Cylinder
An unlagged hot water cylinder can waste a surprising amount of energy over the course of a year, so fitting a insulating jacket, which are cheap to buy and simple to fit, is an important step towards saving money and energy in your home.
When choosing a water cylinder jacket, make sure you go for one which is at least 75 mm-100 mm thick and that it carries the British Standard Kite mark. Measure the height and circumference of your water cylinder before you go, and if in doubt, buy a slightly larger jacket rather than one that is too small. As mentioned above, water cylinder jackets are very simple to fit. Simply wrap the jacket around the tank and secure it using the supplied ties or attached strings.