Top up your loft insulation safely

Use this guide if your loft has thin or patchy insulation and you want to cut heat loss before winter. You need a torch or head torch, a tape measure, a dust mask rated for fibres, goggles, gloves, long sleeves, a craft knife with a long blade, and something safe to kneel on across the joists.

Step by step

1. Inspect the loft and measure what is there

   Go up with a torch in daylight and kneel only on joists or boards, never on the ceiling plasterboard between them. Push a ruler down into the existing insulation at several points and write down the depth. Current guidance from bodies such as the Energy Saving Trust recommends around 270mm of mineral wool, but check their current figure before you buy. Stop and seek advice if you see loose grey-brown or gold granular insulation, as older vermiculite can contain asbestos and must not be disturbed.