How to boost gas and wood fire heating efficiency

How do you heat your home? Both gas and wood-burning heating can be effective, but they need to be used with safety in mind. Here are a few pointers to help you boost your gas or wood heater's efficiency.

Burning gas produces carbon monoxide, carbon dioxide, nitric oxide and nitrogen dioxide, as well as small amounts of formaldehyde and sulphur dioxide. This process also creates water vapour, which can in turn increase levels of condensation and mould.

• For cleaner air, choose a flued heater, that will channel toxic fumes outdoors via a pipe or chimney.
• Unflued heaters are generally less expensive and less energy efficient than flued heaters (to compare gas heaters, check their Energy Rating labels). If you do choose an unflued heater, make sure the room you use it in is well ventilated. If there are no air vents, or they are blocked, open a window or door regularly to let pollutants out.
• Don't leave an unflued gas heater on overnight or use one in a bedroom or bathroom.
• To monitor oxygen levels in a heated room, choose a heater with an oxygen depletion indicator. It will let you know when the oxygen level is low. Overheating indicators are also a sensible safety precaution.
• Choose a gas heater with electronic ignition rather than a pilot light that burns constantly. If you have a heater with a pilot light, turn the pilot light off in summer when you are not using the heater.
• To help make running your gas heater even more safely, make sure you have carbon monoxide detectors installed your home and in working order.

Burning wood can be a positive choice from an environmental point of view as it has minimal greenhouse impact if the wood is obtained from a sustainable source and not transported far. Overall, however, it is an inefficient form of heating because so much of the heat from a wood fire is lost as it circulates around your home.

• Make sure your wood comes from a sustainable source such as a timber plantation.
• Make sure you use clean, high-quality wood that has been dried, or 'seasoned', for at least a year. This will help minimize air pollution.
• Do not collect firewood from parks as it provides vital habitat and nesting material for animals.
• Do not use wood that has been coated with varnish, paint or other chemicals as it could emit toxic fumes. Driftwood may contain chemicals as well as salt that can erode or rust a fireplace.
• Don't let logs smoulder for long periods, such as overnight, as this increases the output of pollutants.
• Have your chimney checked and cleaned once a year to make sure it is working efficiently.
• Add wood ash to your compost – it's an excellent source of potassium, which promotes healthy plant growth.
• To improve the efficiency of an open fire, install a fireplace insert. This is a metal frame that allows air to circulate around the fire in the fireplace, pick up heat and then flow back into the room. One of these inserts can raise the efficiency of an open fire by up to 35 per cent.
• Fit a fan to your wood heater. It will help circulate warm air and can raise your heater's efficiency by up to eight per cent.
• If burning wood will be your main heat source, install a slow-combustion heater. These are cheap to run, emit minimal pollutants, and operate at up to 70 per cent efficiency, compared with 10 per cent for an open fire.
• About 90 per cent of the heat from an open fire goes straight up the chimney.
• To help make running your wood heater even more safely, make sure you have carbon monoxide detectors installed and in working order.

If you're trying to decide between gas and wood heating, keep these points in mind to help you make the best choice for your home.