Draught proofing quite simply involves sealing any gaps through which cold air is entering your home. Commonly these gaps appear around doors, windows, the loft hatch and chimneys. Draught proofing is a relatively simple measure with potentially very low cost that should improve your thermal comfort.
Ventilation: When reducing draughts and improving air tightness of your home, ventilation needs to be considered. Wet rooms such as kitchens and bathrooms need ventilation to reduce the build-up of moisture in the home. A build-up of moisture can lead to damp and mould. If adequate ventilation is not already in place, consideration should be given to upgrading ventilation in these rooms by the inclusion of extract fans or, where possible, passive stack ventilation. Draught stripping of internal doors can reduce over-ventilation of the rest of the house and lead to significant improvements in comfort.
Background ventilation can be provided by window trickle vents. These vents are often present in new windows and can be fitted to some existing windows. It is important to ensure that existing or proposed combustion devices are not starved of air (i.e. is there suitable provision for an independent supply of combustion air). Any room with an open fire (solid fuel or gas) or a boiler with an open flue will normally require an airbrick as trickle vents will not provide adequate ventilation.
Areas for attention: Draughts from below suspended floors can be much worse than those from windows and doors, so consideration should be given to sealing the floor. Hardboard fixed to wooden floors can be effective. Sealing around the junction between the floor boards and the skirting, and on top of the skirting where it meets the wall is recommended. The use of polythene sheet to draught proof floors is not recommended, particularly in wet areas. Other areas that should be sealed against draughts include the loft hatch and any point where pipes or cables penetrate the internal walls, floors or ceilings.
Draught stripping single glazed windows can lead to higher levels of condensation on the window-panes. Good secondary glazing can be a very effective draught seal that will also reduce condensation. If secondary glazing is installed the original window should not be draught proofed, as this could lead to a build-up of condensation between the secondary and original glazing. If secondary glazing is installed consideration needs to be given to exit options in emergencies such as fire. Gaps below or above external doors and around letterboxes can also be a source of draught and can be sealed using brushes.