Sash and case windows in Edinburgh: repair, draught-proof or replace?

Most sash windows are repairable — that is the point of them

A sash and case window is a repairable object by design. The sashes come out, the cords are replaced, decayed sections of the bottom rail or cill are cut out and spliced, and the whole thing goes back. Failure is almost always local: a snapped cord, a rotten sill end, paint that has bound the sash into the frame, putty that has given up.

That matters in Edinburgh because a large share of the housing stock is pre-1919 and much of it is in a conservation area or listed. In those cases replacement in a different material or profile can need consent, while a careful repair generally does not — so repair is often both the cheaper and the simpler route.

• Snapped cords and sticking sashes are routine repairs, not a reason to replace.
• Localised rot in the bottom rail or cill can usually be spliced out.
• Draught-proofing brushes and a service typically stop the rattle and the worst of the cold draught.
• Secondary glazing is often more acceptable than replacement on a listed or conservation-area building.

What draught-proofing does and does not do

Draught-proofing a sash window means routing discreet brush seals into the sashes and staff beads, easing the sashes so they run properly, and renewing the cords while they are out. It stops rattle and cuts the cold air moving through the gaps, which is what most people actually feel on a windy night on a Marchmont top floor.

It does not turn single glazing into double glazing. Glass is still glass, so the heat loss through the pane remains. If the cold surface is the problem rather than the draught, the honest options are heavy curtains or secondary glazing rather than a brush seal.

When replacement genuinely is the answer

Sometimes the frame itself has gone — widespread rot through the case, boxes that have been butchered by previous work, or a window that was already replaced badly in the 1980s in a material that will never match. In those cases replacement is reasonable, and on a listed building or in a conservation area the specification matters: profile, glazing bar sizes, materials and opening pattern are all things the council may look at.

The order to keep in mind is straightforward — survey first, then decide. Anyone quoting for replacement windows without having looked at whether the existing ones can be repaired is quoting for what they sell, not for what your building needs.