Insulation

• Loft insulation
• Cavity wall insulation
• What if you have solid walls?
• Draught proofing
• Hot water cylinder jacket
• Ground floor insulation
• Double glazing

The average home wastes energy through the building fabric. This is energy that you pay for and which is heating the air outside your home! In general, newer homes waste less energy than older ones, and flats lose less energy than houses. For a typical semi-detached house:

• 35 per cent of energy is lost through walls
• 30 per cent through the roof
• 20 per cent through windows
• 15 per cent through doors and floors

These figures are a guide and will vary depending on the type of property. Clearly, it is very important to insulate the roof and walls, as this is where most heat is lost.

There are a number of ways in which you can improve the energy efficiency of a home. Energy efficiency improvements will pay for themselves in time, because they save money on your heating bill. The time taken to pay for themselves is known as the 'payback period'. The following are the main energy efficiency improvements, with the approximate payback period for each:

• Cavity wall insulation - payback in less than two years
• Loft insulation - payback in around one year
• Draught proofing doors and windows - payback in around four years
• Hot water cylinder jacket - payback in around six months
• Ground floor insulation - payback in less than three years

Loft insulation

Loft insulation is the most cost-effective energy efficiency measure. The most common form of loft insulation is a mineral wool quilt which comes in roll form. Everyone in Plymouth is entitled to a discounted rate for professionally installed loft insulation – it may even be free! Ring 0800 512 012 to find out what discounts you can qualify for.

Current Building Regulations require a depth of 250mm to 300mm of insulation. If you already have loft insulation of 50mm or less you should consider topping it up.

Cavity wall insulation

Cavity wall insulation is the second most cost-effective energy efficiency measure. If your home has cavity walls it is wise to install cavity wall insulation. In general, homes built since about 1930 have cavity walls. The insulation is installed by drilling holes into the mortar between bricks in the outer skin of the wall and pumping or blowing the insulating material into the cavity. The installer will fill holes with mortar that matches the existing colour as far as possible. Everyone in Plymouth is entitled to a discounted rate for professionally installed cavity wall insulation - it may even be free! Ring 0800 512 012 to find out what discounts you can qualify for.

What if you have solid walls?

Most homes built before 1930 have solid walls and are often referred to as 'hard to treat'. This is because the only means of insulating the walls are very expensive and disruptive. The most common forms of solid wall insulation are internal, such as dry-lining, and external, such as thermal render. 'Period' homes can be particularly difficult to insulate if they have features - like dado/picture rails or a particular external appearance.

Draught proofing

Draught proofing doors and windows will cost from about £80, and can improve comfort as well as reduce energy bills because draughts are reduced. Various types of seals and brushes are available for doors and windows. Letter box covers are easily fitted.

Hot water cylinder jacket

If you have a hot water cylinder and it is fairly new it will have 50mm to 80mm of factory-applied sprayfoam insulation. Older cylinders will require insulation with a jacket, which should be about 80mm thick. It will cost about £10 to £20.

Ground floor insulation

Common forms of floor insulation are mineral wool quilts, rigid insulation boards or blown insulation. Installing insulation - below floorboards for example - can be disruptive. It is best done when running heating pipes under the floor or rewiring, when floorboards might need to be lifted anyway. Moving into a home is also a good opportunity. Floor insulation is particularly beneficial in detached houses, where heat loss through the floor perimeter is highest. Materials will cost from about £100.

Double glazing

Double glazing will improve the energy efficiency of your home. However, you would not replace windows to improve energy efficiency; you would replace them because they are beyond economic repair. It is not therefore strictly an energy efficiency measure, mainly because it is extremely expensive and will never pay for itself in reduced heating bills. Because of this, grants such as Warm Front are not available for double glazing.

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