Loft Insulation

How much can I save?

If you increase your loft insulation from none to 270mm deep

Annual Saving per year : £180 -£220
DIY Cost : £275
DIY Payback : 1 - 2 years
CO₂Saving per year : 1.5 Tonnes

If you increase loft insulation from 50mm to 270mm deep

Annual Saving per year : £50 -£60
DIY Cost : £240
DIY Payback : 4 - 5 years
CO₂Saving per year : 410 kg

(Source : Energy Saving Trust)

How do I know if I need to insulate my loft?

Tell tale signs include :

Cold house ( I know it's pretty obvious isn't it?)
House cools down rapidly as soon as heating is turned off
Older houses are more likely to poorly insulated

To find out have a look! I told you that it would be a straight forward guide! If the insulation looks very old, is non-existant or is less than 270mm deep (that's about 11 inches in English) you should really get on and do something about it.

You can even do it yourself if you are that way inclined. Dick Strawbridge and his team of three on It's Not Easy Being Green insulated the loft of a terraced family home in just 30 minutes. In many cases it is not a big job and certainly something an enthusiastic DIYer can complete without too much effort or cost.

How is it installed?

The insulation material is simply laid over the floor of the loft, between the joists if they are exposed and then over them as the depth increases. Ecofreak recommends Thermafleece as it is totally natural, is nicer to work with than synthetic insulation and helps to support UK sheep farmers.

The work can be carried out by a professional installer or done as a DIY project. I have detailed a few pointers for the DIY enthusiasts amongst you below.

Installation Tips - avoid squashing the insulation down under the eaves or to make it flush with the top of joists. When insulation is compressed it loses a great deal of effectiveness. Laying insulation over the top of the joists as well as between them stops the joist themselves conducting heat away from your home and into the loft.

Loft access - if access to the loft is required (to reach cold water tank etc) consider laying additional bearers on top of the existing joists so that walk boards can be firmly attached to these above the height of the newly installed insulation.

Electrical cables and light fittings - Avoid covering highly loaded cables and light fixtures as they require sufficient ventilation to prevent overheating.

Cold water tanks - you should take care not to insulate below the cold water tank (if one is present). This will help to prevent it freezing and also ensures that the insulation does not get wet from any condensation forming on the tank. If a cold water tank is present and is uninsulated it would be a good idea to "lag" this at the same time to further reduce the chances of it freezing during a cold period of weather.

Water pipes - it is good practice to lag water pipes running through your newly insulated loft. This will prevent cold pipes from freezing and warm pipes from losing heat.

Loft ventilation - by insulating your loft you will make the loft space colder and therefore more susceptible to condensation. It is therefore important that the loft is sufficiently well ventilated to prevent condensation from forming. The need for additional ventilation will depend on the roof type and existing ventilation measures.

Are there any grants available?

Yes. In many areas there are grants available towards the cost of insulating your loft. Check out the Energy Saving Trust website http://www.est.org.uk/ or contact your local council for details.

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