Insulation

FOCUS ON

Adequate insulation is an essential component of an energy-efficient property. It limits the amount of heat lost through a building’s floor, walls and roof, helping to maintain a comfortable temperature all year round and keep heating bills to a minimum. Though a single upgrade will result in better efficiency, a whole-house approach has the greatest effect.

ON A ROLL

Often used for covering the floors of lofts, blanket insulation is also suitable for lining the underside of a pitched roof, internal stud walls and suspended timber floors. It comes in rolls of material including mineral, sheep’s, fibreglass, wood-fibre, plant-fibre and recycled plastic wool, and it’s flexible and easy to cut and fit, making it suitable for competent DIY-ers to install themselves. Prices start from around £5 per sqm for fibreglass.

When insulating a loft floor, the material is usually laid between and over the joists, avoiding air vents, grilles and bricks. If the space has no ventilation, you may need an airbrick or similar to prevent a rise in humidity and damp problems. Water tanks, pipework and loft hatches should be insulated too. When fitting blanket insulation in an existing loft, there is no requirement to apply for Building Regulation approval unless you are also changing the roof covering, in which case current standards must be met. Follow the product manufacturer’s installation guidance.

A HARD CHOICE

Rigid insulation board comes in a choice of panel sizes and materials with products suitable for interior and exterior applications to the roof, floor and walls.

Options include wood fibre, cork and plastics. ‘Wood fibre is breathable and lets moisture pass through it, reducing condensation risks in older buildings,’ says architect Ben Ridley from Architecture for London (architectureforl