Energy bills are set to rise by as much as 40% this winter. This will take the average household bill for gas and electricity for customers on standard plans to over £1,800 for the year. With many consumer organisations and action groups forecasting a steep rise in the number of people who will have difficulty paying their bills, it is a good time to look at ways to reduce energy and heating costs.
There are a number of relatively easy and inexpensive measures that people can employ to keep fuel and energy costs down. Additionally, grants are available from a wide variety of agencies to improve the energy efficiency of your home.
Insulating the loft
Insulation is the first line of defence in the fight against high energy bills, for around half the heat lost in a typical home escapes through the walls and the roof. It is estimated that around 25% of heat is lost through an un-insulated loft, costing the average household £155 per year. And although the sparrows perched on your roof will have warm feet, they won’t be contributing towards your heating bills.
Fortunately, a number of easy to install loft insulation materials are available to remedy this problem. These will either come in the form of rolls of blanket insulation or in bags of loose-fill insulation, both of which are laid between the joists.
Blanket insulation is made from mineral wool and is available in large rolls. Although an effective insulation material it can cause skin irritation and care should be taken when laying this material. Today there are a number of alternatives to mineral wool including sheep’s wool and recycled plastic bottles. This highlights the growing demand for building materials that are ecologically friendly as well as providing a cost effective solution.
Loose fill insulation comes in bags and is poured between the ceiling joists. The most common type of loose-fill insulation is vermiculite granules (a crushed igneous rock); other materials used for this form of insulation are cork granules, mineral wool and cellulose fibre.
Whatever insulation material you choose it is crucial to lay it at the correct thickness to achieve maximum thermal efficiency. The Energy Saving Trust – a non-profit organisation set up to promote the efficient use of energy – recommends a thickness of 270mm for all loft insulation.
Many homeowners already with loft insulation may find it has been laid at a thickness well short of this figure. One reason for this is that in the past it was considered adequate to install insulation to the top of the ceiling joists, which would achieve a thickness of 100mm to 150mm.
If the blanket insulation in your loft is not the correct thickness, simply add another layer or layers of insulation until the recommended thickness of 270mm is achieved. Shallow ceiling joists, however, present a different problem if loose fill insulation has not been installed to the correct depth. To create the required depth of 270mm it will be necessary to fix lengths of timber to the top of the joists. Once again this is not a difficult job and well within the capabilities of anyone with even limited DIY experience.
Cavity wall insulation
In homes without insulation it is estimated that a third of all heat lost escapes through the walls. Many houses built since1920 are constructed with exterior walls made up of two skins – an outer wall built from brick and an inner wall built from block – with a narrow gap of about 50mm between them. To dramatically reduce heat loss the cavity between double-skinned walls can be filled with an insulating material.
Holes of about 25mm diameter are drilled through the mortar of the outer wall and then the insulation is injected into the cavity from outside. It is mess free and quick to install; the whole process taking around two to three hours for an average sized property. Once the installation is completed the contractor will plug all the injection holes with mortar, matching it as closely as possible to the colour of the existing mortar.
But first it needs to be established whether your property is suitable for this type of insulation. If you have a traditional brick built property there is a simple test you can carry out to see if it has been built with cavity walls. This involves checking that no brick ends (headers) appear in the wall, for this is an indication of a solid wall construction. Other influencing factors include:
- Living in an upper story flat. The insulation material fills the cavity from ground level, therefore if your neighbours below are not in agreement, the process can’t be carried out.
- The cavity has already been filled. Since 1982 most houses have been built with cavity wall insulation.
- The property has a problem with damp. This must be remedied before cavity wall insulation is installed.
- Structural problems such as cracking and flaking brickwork or the erosion of the pointing also need to be made good. These problems are often indicators of damp.
- Rubble or other debris at the bottom of the cavity and mortar on the wall ties can also be a problem, for it creates a bridge allowing damp to penetrate from the exterior wall to the interior.
- A cavity width of less than 50mm is unsuitable for this form of insulation.
Cavity wall insulation is suitable for terraced and semi-detached houses even if the neighbours don’t wish their property insulated, as the contractor can install a cavity barrierat the party wall between two properties.
Three types of insulating material are used in cavity wall insulation: mineral wool, polystyrene beads and Urea Formaldehyde (UF) foam. Tests have shown all three materials share a similar insulation value.
Although a relatively simple operation, cavity wall insulation is specialist work that needs to be carried out by trained technicians with the expertise and equipment to ensure the insulation is filled to the correct density. Look for a contractor whose work is covered by CIGA (Cavity Insulation Guarantee Agency), as the work will be guaranteed for 25 years.
Draught proofing
Draughts caused by the gaps between the floorboards, the letterbox, unused open chimneys, and ill-fitting windows and doors can account for 20% of heat loss. Fortunately, problems of this nature are easily resolved with simple, inexpensive forms of draught proofing.
- Block that undercurrent of cold air coming from between the floorboards by filling the gaps with acrylic sealant.
- Fit draught excluder strips that come in the form of small bristles around the letterbox.
- Stop heat disappearing up an unused open chimney with an inflatable chimney balloon. Available in different sizes, the chimney balloon is placed about 300mm up the chimney and inflated by mouth through an inflation tube supplied with the balloon.
- Repair or replace ill-fitting doors and windows and fit door strips to the bottom of doors. Easy to fit adhesive draught excluder comes in rolls and is available from most DIY stores. Gaps under and around doors can result in 11% of the heat escaping from your home.
Keep the warmth inside and reduce your heating bills by turning your home into a draught exclusion zone.
Lagging
Lagging is the term used for insulating hot water pipes, radiators and hot water tanks. It involves using a non-conductive material to prevent heat loss.
Foam tubes are used to lag hot water pipes and are available in a range of pipe diameters. Foam lagging tubes usually have a cut running along their length to facilitate fitting them onto the pipes. Some foam lagging tubes have a silver foil lining to reflect heat back into the pipe.
If your hot water tank is not pre-insulated you should fit the tank (sometimes called a cylinder) with a cylinder jacket. A cylinder jacket comprises of a number of plastic segments containing mineral-fibre insulation and will cut heat loss by 80%. The jackets come in a range of sizes and are held in place by metal straps.
Radiators positioned against an outside wall can lose up to 25% of their heat to the wall behind it. This is a serious waste of energy and money. Fitting a foil-faced expanded polystyrene lining behind the radiator can save up to half the heat which would otherwise be lost.
The best time to do this is when you are decorating and have removed the radiators to paint or wallpaper behind them. But waiting to redecorate before carrying out this task is not always convenient. Fortunately, the foil-faced expanded polystyrene lining can be fitted without removing the radiator.
All these lagging materials are available from most DIY stores.
Secondary glazing
Double-glazing is an excellent way of reducing the estimated 20% of heat lost through the windows of an average sized property. But the cost of double-glazing can be prohibitive for some homeowners or may not be permitted if the property is situated in a conservation area.
If this is the case an effective alternative is secondary glazing. Secondary glazing involves fitting another window in the recess of the existing window. As well as providing thermal insulation secondary glazing can lessen noise pollution and reduce condensation. There is a range of systems available for different budgets and styles of window.
Although inexpensive products using clear acrylic sheets fitted to UPVC or plastic frames are popular, their effectiveness can be short lived (about a year). The best option employs an aluminium glazing system anchored in a hardwood sub-frame.
Some manufacturers offer installation as part of their service, but installing secondary glazing can be carried out by anyone with relatively little DIY experience. The sub-frames are usually pre-drilled so only need fixing in the recess of the window. The tools needed to carry out the job are a spirit level, tape measure, power drill and screwdriver or cordless screwdriver. If you plan to fit the secondary glazing yourself, the main points to remember are:
- The existing or primary window should be made draught proof before fitting secondary glazing.
- For optimum noise reduction the gap between the panes should be about 100mm. But remember if the gap is much greater than 100mm, there will be room between the panes for thermal currents, which decrease the insulation value.
- Follow the manufacturer’s instructions for taking accurate measurements of your window.
- Use a spirit level to ensure the frame is perfectly vertical.
Energy saving appliances and lighting
In the average household lighting contributes to about 15% of the electricity bill. Replacing standard light bulbs with energy saving bulbs can reduce the amount of electricity consumed by one fifth. Although a little more expensive, energy saving bulbs on average last ten times longer than conventional bulbs.
Homeowners with a central heating system can make further savings by fitting thermostatic radiator valves. This type of valve controls the flow of hot water to the radiator and as the heat level reaches the pre-set temperature the flow is reduced; as the room temperature falls the hot water flow is increased and more heat is generated.
Thermostatic radiator valves allow different temperatures to be set in different rooms. So in cold weather the rooms used more frequently can be heated at a higher temperature than rooms that are unoccupied or rarely used, making the central heating system far more energy efficient.
If buying new electric appliances look for those that have an Energy Saving Recommended label. These appliances have been independently tested and found to be more energy efficient without impairing performance. Domestic appliances tested under the scheme include fridges, washing machines, dishwashers etc.
The energy consumed by televisions, DVD players and hi-fi systems left on standby makes up a staggering 8% of an average household electricity bill. So when not using these appliances – switch them off.
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