Sash window restoration cost varies significantly depending on the condition of the window, the extent of timber decay, whether cords and mechanisms need replacing, and whether you're upgrading glazing at the same time. A window needing a cord replacement and a service is a very different job to one needing significant timber splicing or partial rebuilding, which is why a proper on site assessment, rather than a generic estimate, is the only reliable way to get an accurate figure.
The main variables are the extent of timber decay (a simple cord replacement costs far less than splicing in new timber sections), whether the sash needs to be removed to a workshop for more extensive repair versus fixed in place, whether draught proofing is included, and whether you're adding slimline double glazing or secondary glazing alongside the structural repair.
In most cases, yes, per window, restoration costs less than a full replacement window and frame, particularly once you factor in that replacement on a listed building or in many conservation areas typically requires planning permission or listed building consent, adding both time and cost that restoration usually avoids entirely.
For multiple windows, a phased approach is often more practical than tackling every window at once, both for cost spreading and to avoid being without windows in several rooms simultaneously. We typically survey the whole property first, prioritise by condition, and sequence the work accordingly, so you have a realistic overall figure and timeline before committing to the first phase.
Be wary of a quote that hasn't included an actual inspection of each window's condition, since the biggest cost variable, the extent of timber decay, can't be accurately assessed without one. A quote based purely on a phone description or photos is likely to be a rough estimate rather than a reliable figure.
The most reliable approach is a proper site survey assessing each window individually, since even windows of the same age and style in the same property can be in quite different condition depending on their orientation, exposure to weather, and maintenance history.
Not directly in terms of the restoration work itself, but if consent is needed for any aspect of the work (typically only relevant if you're changing the glazing type, not for straightforward repair and draught proofing), the time and, occasionally, cost of the consent process is worth factoring into your overall project timeline and budget, even if it doesn't change the trade cost of the restoration itself.
Yes. Draught proofing alone, without any structural repair, is a relatively low cost way to improve comfort immediately, and can be a sensible first step if a fuller restoration needs to be phased over time for budget reasons. It's not a substitute for addressing genuine timber decay, which will still need attention eventually, but it's a reasonable way to sequence spending if the whole job isn't affordable at once.
