| Insulation = stopping heat loss | |
| In the average British home approximately 30% of the heat produced by a central heating system is lost through the roof, walls and floors. This is a complete waste that can be almost totally eradicated. | |
| Through the roof | |
| About 20% of the household's energy bill can be saved by installing good loft insulation. Good means a minimum depth of 150mm (6 inches in old money!) and even better 200mm (8in) - with glass fibre or 140mm using sheep's wool - see below. This is not rocket science. Really good quality loft insulation is available from all DIY stores and the fibre-glass stuff even comes now with plastic wrapping to avoid damaging your hands. | |
| Preferably you can go "green" and insulate your loft with sheep's wool - considerably more expensive than fibreglass but almost carbon neutral (that is it only uses about 15% of the energy required to manufacture fibre glass) and it lasts a lot longer too, up to 50 years. I like this concept and anticipate prices coming down steadily as more and more farmers make their product available. Being a natural fibre from a totally renewable source sheep's wool insulation has a fantastic energy balance. Wool can rapidly absorb and release moisture and so helps keep buildings cool in summer as well as warm in winter. |
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| The
great thing about modern insulation products, and here I mean
particularly wool, is that they are easy to handle. Ok, it's a bit
of a cliché - the picture that is, but wool is totally harmless and can
be installed without any protective clothing whatsoever
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| A typical house has a loft space of around 70sqm and insulation will cost you anything from £3/sqm for basic fibre glass up to £10/sqm for max thickness wool products. So you are looking at spending up to £700 to lag the entire loft space. This measure will save you 15-20% on your energy bills so you can do the math pretty easily to work out payback. I reckon 3 - 5 years payback in most houses with standard products. Get in touch if you have any queries or would like to obtain details of what and where to buy. | |
| Through the walls | |
| Up to half of the heat loss from an average house is through the walls because of a simple physical phenomenon called conduction. Heat naturally passes from a warm room to a cold wall and never re-enters the room unless the room temperature falls below that of the wall - doesn't happen, so you need to insulate your walls to stop this. | |
| First way of
achieving this is to insulate behind your heat emitters - radiators,
storage heaters, convectors - whatever. If there is an air gap then
the wall behind the heater should be insulated - ideally using a
proprietary product such as Heatkeeper
panels although silver foil will have some
effect. The great thing about Novitherm panels is that they boost
the heat output and generally reduce heating bills by around 15%.
Typically it will cost you around £40 to install these panels behind all of your radiators and give payback within 2 -3 years in most cases. |
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| Next
thing you can do is insulate cavity walls - basically done by filling the
cavity with insulating fibre, foams or beads. Surface insulation is
available if you don't have wall cavities but this may reduce room sizes
and effect decoration.
Cavity wall insulation will cost you around £350-450 and pay for itself within 7-10 years. By the way - if you are in an old house - and especially in Scotland - cavity wall insulation may not be a great idea as it can inhibit the ability of the building the "breathe" - discuss with your insulation contractor and make sure you have a guarantee in respect of avoiding condensation, damp problems. |
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| If you are building a house then naturally you would do well to include wall insulation from the outset and sheep's wool is fantastic for this purpose, coupled to a vapour-permeable breather membrane used on the cold side to inhibit cold air infiltration and reduce conduction losses generally. | |
| Draught Exclusion - Doors & Windows | |
| Draughts are an obvious signs that you have a poorly insulated home. The good news is that they are often easily sorted. | |
| Draught-proofing of windows and doors is a simple DIY job but beware - never draught proof a room with an open fire or gas fire that does not have a balanced flue or an airbrick near the fire. | |
| Double and even triple glazing is a very popular way of reducing heat loss although it will not save as much energy as for example cavity wall insulation. | |
| When you do replace windows ensure you ask for Low E glazing as this has significantly lower heat loss characteristics than conventional glazing. You can also specify Argon filled glazed units for extremely low heat transmission and specify that the gap between the panes is at least 12mm or even 20mm for reduced energy loss (and noise!). | |
| Typically draught proofing doors and windows will cost you between £50-60 and save you £10-20 a year giving 3-5 year payback and improved comfort. | |
| Double glazing - with Low-E - will cost you a lot and save you a little - with apologies to all those double glazing salesmen out there - you might spend as much as £3000 to save £35 a year so don't do it just to save energy. | |
| Contact me anytime to discuss your queries | |
