Draught Proofing

A simple inexpensive way to reduce the heat loss from your house is to draughtproof the windows and doors. Draughts are caused by cold air forcing its way into the house through gaps in the roof, up through floors, through vents or cracks around windows and doors and then forcing its way out through other gaps. Draughts may also occur when air is sucked in from outside to replace air used by boilers and fires.

If you block the gaps where the air is coming in you will stop the draught. Although the house will be more comfortable if you prevent streams of cold air moving through it, you must have controlled ventilation to keep the air fresh and remove excessive moisture.

Fires and boilers need air to burn efficiently and safely. Vents should be as close as possible to the appliance so that air passing to it does not cause a draught. They must never be blocked off or fumes may be sucked down a chimney, with possible lethal results. If the air has to pass across a room, fit the vent above a door or high in a wall so that air entering is mixed with the warmed air in the room before it moves to the fire.

Never block out the draught designed to pass under the house dry rot may develop if the timber is not well ventilated. You can keep cold air out of the house by draughtproofing the floor from inside. Smilarly, there must be some form of ventilation in the loft to prevent condensation.


Heating bills can be reduced by 60c on every euro by installing draughtproofing and insulation. But how much you actually save depends on the cost of the work compared to the saving in fuel. For example, the estimated heat loss through windows can be reduced by half if you install draughtproofing and double glazing. It might take 40 years to recover the cost of custom-made double glazing but only two or three years for a DIY system.

Insulating the loft and draughtproofing doors, windows and floors are the most cost-effective forms of insulation. Similarly, it is worth paying for cavity wall insulation as the cost will soon be recovered from savings in fuel.

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