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The Savings

Simply by insulating your loft to the recommended 270mm depth you could save you as much as 30% a year on your heating bills and nearly 1 tonne of CO₂ per year.

If every household insulated their loft just to the recommended minimum it is estimated that the savings would be enough to pay the annual fuel bills of millions of families.

Methods of Loft Insulation

There are a number of different methods of loft insulation and these are summarised as follows:

• Blanket Insulation

  Glass fibre, foil-backed felt, rock fibre or mineral fibre blanket insulation is available by roll. These rolls fit snugly between the joists. This is probably the most common type of insulation. Rolls are available in 75mm (3inches) and 100mm (4 inches) thickness.The width of rolls range from 300mm (1 foot) to 1200mm (4 feet).The lengths of the rolls range from 5m (16 feet) to 9.4m (30 feet).

• Granular Loose fill Insulation

  Cork granules, exfoliated vermiculite, mineral wool or cellulose fibre are all forms of loose fill insulation. This may not be the best method to use in a very draughty loft space, as the draught can cause the fibre to blow about in high winds. However it is easy to apply and is especially useful for areas where joists are irregularly spaced and where pipes or other obstructions make it difficult to lay a blanket insulator

• Sheet insulation

  materials include polystyrene, polyurethane and polyisocyanurate boards. Many of these were until recently, or still are, blown with gases which deplete the ozone layer. Some are now available which are Zero ODP (Ozone Depletion Potential), which means that the blowing gases won′t damage the ozone layer. All of these boards will need to be Zero ODP by 2004.These insulation materials have the best insulation value of any commonly available insulation material, but they do require large amounts of energy to produce, and consequently have high ′embodied energy′.In general these insulation are best used, where no easy alternative is available for vertical applications, masonry cavities and lining attic roofslopes.Blown Fibre Insulation:A professional contractor can be employed to blow fibrous inter joist insulation, via a hose. This may not be the best method to use in a very draughty loft space, as the draught can cause the fibre to blow about in high winds. The contractor should be able to advise you.

• Natural Insulation

  Options: There are a number of natural insulation options. Two examples are Warmcel100 and Thermafleece.Warmcel 100 Warmcel 100 is a ready-to-lay cellulose fibre loft insulation, which is very safe and easy to lay, and helps protect the environment.It is an excellent alternative to glass and mineral fibre insulation quilts in your loft, and is suitable for full insulation or just to top up your existing insulation. It is only recommended where the roof is ′felted′, i.e. has roofing felt or membrane laid under the slates or tiles, as a secondary protection against water ingress.Warmcel 100 is manufactured from fire-retarded recycled newspaper. It is designed, and only really suitable for, loose filling lofts where it offers a real cost-effective alternative to mineral fibre insulation. This product puts to good use paper which would otherwise go to landfill. When, eventually, it is removed from a building, it can be recycled again or disposed of safely, without creating toxic waste or biodegrade-ability problems.Thermafleece is manufactured from pure British sheep wool. It is suitable for sloping ceilings and roof slope insulation, as well as stud walls and dry lining. It is more expensive than mineral fibre insulation or Warmcel 100.Thermafleece uses blended sheep wool from British hill sheep. This wool is often of low economic value, so the production of Thermafleece is renewable, recyclable and is promoting the economies of some of the poorest rural areas in the UK.Installation.