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Q. Is it true it costs more to switch lights off and then on again, than it does just to leave them switched on?
A. It's a myth that it costs more to switch your lights on and off than to leave them running.
Old-fashioned incandescent bulbs - the kind with a filament in them - don't draw any more power than normal when they're first turned on - if a bulb says 60W on it, it will draw 60W of power from the instant it's switched on.
With low energy-saving bulbs, it's again cheaper to switch lights off when you leave a room than to leave them switched on.
While low energy bulbs do draw more power in the first few minutes of being switched on than they do when they are running normally, the energy used by them starting up is only the equivalent of leaving them running for a few minutes.
Q. Is it cheaper to leave the central heating on at a low temperature rather than switch it on and off as needed?
A. It's a common misconception that it's cheaper to leave your heating on all the time.
Boilers use more power initially to heat radiators from cold. However, the cost of doing this is greatly exceeded by the cost of keeping the boiler running all of the time - even if you set the temperature of the central heating down low.
You should set your heating to come on shortly before you are going to need it - for example, before you get up in the morning or before you come in from work - and to go off again at a time when you leave the house.
Q. Are there energy-saving light bulbs which don't take ages to reach their full brightness?
A. Some energy-saving bulbs can take a little longer than normal bulbs to reach full brightness. This is a result of the technology they use, which is also what makes them so much more efficient than traditional incandescent bulbs.
Many modern energy-saving bulbs take little more than a few seconds to warm up to full brightness. You should look for the Energy Saving Recommended label when choosing your energy-saving bulbs, as these have to pass certain criteria on maximum warm-up time.
You can also get energy-saving bulbs which are designed to be fast-start bulbs, meaning that they do not have a warm-up period. Look for bulbs labelled 'fast-start' or 'quick-start' when you are buying new ones.
Q. How do I know if my walls already have cavity insulation?
A. If you want to find out whether or not your home has cavity wall insulation, you can request a free survey from any cavity wall insulation installer registered with CIGA (the Cavity Insulation Guarantee Agency).
Go to the CIGA website or ring them on 01525 853300 for a list of registered installers in your area.
Q. What are the minimum insulation standards that landlords of residential property are legally required to fulfil?
A. Currently, landlords are not legally required to install insulation in residential properties.
However, landlords can claim a tax allowance, known as the Landlords Energy Saving Allowance (LESA); this allows them to claim on their tax return against the cost of buying and installing energy-saving items, including draught proofing, loft insulation, floor insulation, cavity or solid wall insulation, and insulation for hot water systems. The tax relief is for up to £1,500 each tax year per property.
To find out more about LESA, contact your accountant or tax advisor, visit Directgov or call the Energy Saving Trust on 0800 512 012.
Q. Will I save money by turning radiators off in individual rooms?
A. You will almost certainly be able to save money by turning your radiators off in individual rooms when they're not in use. It's a waste of money and energy to be heating a space when it is not needed.
Also, close the doors to any unheated rooms where you have turned off the radiators to help stop the warm air from the heated rooms or spaces escaping into the colder ones.
If you have gas central heating, the one room where you should not turn off, or turn down, a radiator is the room where your thermostat is fitted. This is because it can interfere with the temperature regulation of the central heating.
Q. Is it better to just use the gas fire in my living room to keep my house warm or to heat up the whole house with the gas central heating?
A. Gas central heating is usually more efficient at providing heating compared with a gas fire. It's able to produce more heat per unit of gas used, as a lot of the heat produced by living flame gas fires may escape up the chimney.
Which works out more cheaply for you will probably depend on how many rooms you have or want to heat, and whether you can control the individual radiators in the different parts of your house.
If you cannot turn off or turn down the radiators in the other rooms in your house, you will be better off using your gas fire, as by using the central heating you will be wasting money heating unused rooms.
Q. What's the most effective way of heating my all-glass conservatory?
A. The first thing to consider is whether your conservatory has double-glazed, or triple-glazed glass, or whether it's made of single-glazed panes. If it's single-glazed, it may be difficult to keep it heated to a comfortable level in cold weather. In this case, you could use heaters such as halogen heaters or fan heaters.
If you have double or triple glazing, then the conservatory will be better at holding in heat. In this case you can consider fitting a radiator of the type you have in the rest of your house.
Finally, building regulations may require that any heat source in a conservatory is controlled independently of the heating in the rest of the house. This means that anything you install must have a thermostat built into it, and/or allow you to switch it off at its source. It's always best to check with the planning department of your local authority for further advice on this matter.