Insulating heating pipes with foam to consume less
Uninsulated heating pipes lose heat in the unheated rooms such as the garage, cellar or loft. This guide is aimed at beginner DIYers who want to improve their home's energy efficiency at low cost. In one afternoon, you can insulate your whole circuit with pre-split foam tubes.
Choosing the foam suited to your pipes
Closed-cell polyethylene foam is the most common material, sold in rolls or pre-formed tubes. Measure the outer diameter of the pipe with a calliper: the tubes exist in 13, 20, 28 or 35 mm inner diameter. For the thickness, allow 9 to 13 mm for domestic use and 19 mm for very cold areas.
- Measure the outer diameter of each pipe to insulate using a calliper
- Choose the polyethylene foam with the corresponding inner diameter: 13, 20, 28 or 35 mm
- Measure the total length of the circuit to order the right amount of foam
- Cut the tubes to length with a cutter fitted with a new blade and a plank as a guide
- Open each tube along its pre-formed slit and slip it onto the pipe
Fixing the foam and insulating the sensitive points
Slip the tubes along the hot pipes, overlapping them by 2 to 3 cm at the joints. Stick the slits with the supplied adhesive or aluminium tape to guarantee a perfect continuity of the insulation. Do not forget the elbows, fittings and valves: they are the zones that lose the most heat.
The places that matter most
Insulate as a priority the pipes that run through the unheated volumes: garage, cellar, crawl space and loft. The first metres after the boiler are also critical, because they carry the hottest water in the circuit.
Precautions and mistakes to avoid
- Insulating pipes that leak or rust: repair the leak first before insulating
- Choosing a foam that is too small: it deforms and loses its effectiveness
- Leaving gaps between the tubes: each thermal bridge loses heat
- Forgetting the sensitive points such as the valves and elbows
- Using non-flame-retardant foam near the boiler or a heat source
Insulating your heating pipes is one of the most cost-effective energy-saving actions: the material is cheap and the fitting immediate. You will gain comfort, savings and longevity for your installation.