Draught Proofing a Sash Window
Here we look at how installing draught proofing improves a sliding sash window
Anyone that has lived in a home with original sash windows knows only too well the usual problems. The sashes rattle in the slightest hint of wind, they are difficult to slide up and down, one sash may be seized part open and cold winter draughts find their way in around the edges of the sashes. After all original sash windows are designed with gaps so that they are able to slide.
Having them overhauled and draught sealed is a straight forward process which will deliver huge benefits.
The key components are the staff and parting beads, these form the channels along which the sashes slide. Often they are over-painted so the sashes bind. In addition the cord(s) may have broken so the sashes hang at an angle and will not sit flush with the frame. The tenon joints become loose and the frame can twist. All resulting in poor operation and more gaps.
Once the operational problems are sorted out then new parting and staff beads can be fitted. Today these can be fitted with a brush seal, available in different heights to suit the gap in the sashes. Fitting the brush seals will stop air leaking through and also give the sashes something smooth to slide along rather than wood sliding on wood.
Then where the two sashes meet (called the mid-rail) further brush seals can be installed to seal that gap as well.
The difference will be remarkable. The sashes will operate as their original design, reduction in draughts will improve the energy efficiency considerably and external sound would be reduced by up to half.
If you are considering double glazing the existing sashes then always make sure draught seals are fitted, if not then the double glazing will be rendered largely ineffective.