Most draughts are caused by the pressure of the wind against the face of a house, seeking out gaps and cracks. Seal all window and door frames with draught strip, and fit covers to keyholes and letterboxes.
Another form of draught is caused by the convection of air over a cold window pane. Warm air coming into contact with the glass is cooled and falls towards the floor to be replaced by more warm air above, causing draughts. Cure this by fitting double-glazing and well fitting curtains.
Draughts are also caused by the pull of a flue when a solid fuel fire is used in a fireplace. Very considerable amounts of air are required for efficient burning, and this may be pulled across the room from beneath a door. To prevent these draughts, give the fire its own air supply by fitting vents either side of the hearth. Or fit a modern fire grate which has its own underfloor air supply.
You can kill the draught from under a door by fitting a threshold draught excluder to its base, then cutting a slot in the top of the door. This ensures that air enters at ceiling level, where it will be warmed and no longer felt as a draught.
An unused flue maybe pulling up more air than necessary, causing draughts. Block off the flue with a sheet of fire resistant board, but fit a small ventilator in the board so that there is enough air movement to keep the flue ventilated. Failure to do this is often the cause of damp patches on chimney breasts.
Draughts coming up between floorboards can be reduced by laying building paper under a carpet underlay and carpet. On an exposed timber floor, seal gaps between boards with papier mache pressed between the boards and allowed to dry. Then sand and stain to match the floor.
Never block off external air bricks to reduce draughts. They prevent the flooring timbers from developing dry rot.
