Insulating a loft

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One of the ways to make substantial savings on your home heating bills is to insulate the loft. Not only can you save money on your heating bills, you may be eligible for a grant to carry out the work. Your local council or Citizens Advice Bureau will be able to provide you with the relevant information.

Insulating materials for insulating a loft
The two most common forms of loft insulation are blanket insulation and loose-fill insulation. Blanket insulation is made from glass fibre, mineral fibre or rock fibre and is sold in large rolls. All three materials are non-flammable and will have been treated against vermin, damp and rot. The rolls of insulating material are usually 6 - 8m long (20 - 25ft) and up to 400mm wide (16in). The thickness of the material can be 100, 150 or 200mm (4, 6 or 8in), but the thicker the insulation the less heat will be lost.


Blanket insulation
The rolls of insulating material are usually unbacked but can come with a paper backing to prevent tearing of the fibre or a foil backing. Rolls of blanket insulation with a foil backing are used when a vapour barrier is required.
Warm moist air from heated rooms will travel to cold unheated areas such as lofts, producing condensation. Over time this will reduce the effectiveness of the insulation and may even cause dry rot in the roof beams. A vapour barrier is used to prevent this.
The foil backing laid against the warm side of the insulation creates a barrier preventing the warm moist air passing into the loft. Rolls of polythene backed insulation material are also available and will serve the same purpose.


Loose-fill insulation
The most common forms of loose-fill insulation are exfoliated vermiculite and mineral fibre. Loose-fill insulation material is supplied in bags, which will cover an area of