Loft insulation – getting started

by HouseWiz, 31 December 2008

With as much as 25% of heat being lost through the roof of the average house, it’s well worth getting your loft properly insulated – even if you have to shift around all those boxes, suitcases and goodness knows what else to get the whole area done. Don’t forget, too, that your local authority may be able to help with a grant to cover part of the cost.

To do the job properly, you’ll need to prepare the ceilings first. Wherever there’s anything entering the loft from below – wires, vents or pipes, and not forgetting the hatchway itself – make sure that all gaps are properly sealed with mastic. (For the loft hatch, you can buy some foam insulating strip and stick it round the edges of the hatchway.)

There are a few other things to bear in mind:

• Don’t insulate directly under a cold water tank – the heat from the room below helps prevent it freezing in winter (but you will need to insulate the tank’s other surfaces)
• Don’t cover electrical cables or junction boxes – they may overheat. Lay them over the insulation instead, or use clips to attach them to the joists above the insulation
• Make sure you prevent condensation in the loft – you’ll need to either allow proper circulation of air through the loft, or fit a vapour barrier on the warm side of the insulation

The next step is to choose which of the various types of insulation is best for you.