How much does sash window repair cost?
Most of our sash window repairs cost £240 to £380 per window. A full restoration, with the sashes taken out, repaired, draught proofed and re-hung, generally starts from £900 per window, depending on size and condition. Below are our 2026 prices for a standard box sash window.
| Job | Price per window |
|---|---|
| Free stuck sashes and service the window (£120 for a single sash) | £240 |
| Replace the sash cords and service both sashes | £260 |
| Draught proofing and service | £380 |
| Rot repairs to sills and rails | Priced after a survey |
| Full restoration | From £900, priced after a survey |
What affects the price
The biggest factor is the condition of the timber, and we can't always be certain until the sash is out. That is why we give an estimate from photos and an initial survey, then confirm the price once the sashes are out. For windows that are painted shut or hard to reach, we confirm it after a closer survey.
- Window size and type. Large sashes take longer to handle. Bay windows mean three separate windows, often with awkward access.
- Condition of the timber. Sound wood just needs sanding and paint. Exposed areas such as sills and bottom rails often need new timber spliced in or sometimes full replacement.
- Layers of paint. Sashes painted shut for decades take longer to free without damaging the beads and frame.
- Access. Upper-floor windows that can't be reached safely from inside may need a tower or scaffold.
- Glass. Original glass often needs to be retained in conservation area properties. Replacing a pane like for like costs more than standard float glass.
Typical jobs and what they cost
Replacing sash cords: £260 per window
A snapped cord is the most common reason a sash won't stay up. We take out the staff beads, lift the sash out, open the weight pockets and fit new waxed cotton cord to both sides. We always replace both cords. More about sash window repairs.
Freeing a stuck or painted-shut window: £120 per sash, £240 for both
We cut through the paint line, ease the sash free and clean back the runners so it slides again. If it's stuck because the frame has swollen or moved, the job may require a bespoke price for larger remedial joinery work.
Draught proofing: £380 per window
We fit brush seals into the meeting rail of the bottom sash and replace the parting and staff beads with draught-proofed ones. This seals the windows from draughts while eliminating rattling and improving the smooth operation of the sashes. More about draught proofing.
Rot repairs: priced after a survey
Rot usually starts in the sill and the bottom rail of the lower sash. We remove the problem wood and splice in new timber, rather than replacing the whole window. Where possible we strive to use locally sourced wood such as Douglas fir.
Full restoration: from £900 per window
Everything above in one go: the sashes out, cords, repairs, draught proofing, re-hung and ready to paint. Prices for painting can be provided separately upon request. More about full restoration.
Repair or replace?
For most period windows, repair costs less than replacement and preserves the original glass and timber.
Replacement makes sense when most of the frame is rotten, or when the window isn't original and was poorly made.
Poor replacement windows are often a false economy as poorer quality timber rots more easily and can necessitate further repairs or replacement within the next 10 to 20 years.
Listed buildings and conservation areas
Like-for-like repairs don't usually need permission, even on a listed building. Replacing windows often does, and doing it without consent on a listed building is a criminal offence.
- Listed buildings. Repairs that match the original materials and methods generally don't need listed building consent. Replacing a window, or changing its design or glass, usually does.
- Conservation areas. Some streets have an Article 4 direction, which removes householders' usual rights to change windows without planning permission. Swapping timber sashes for uPVC or a different design is likely to need permission there.
- Building regulations. Replacement windows come under the Building Regulations. A FENSA-registered installer can self-certify the work; otherwise it needs building control approval.
If you're not sure, ask your council's conservation officer before any work starts. Cadw's guide to listed building consent and Cardiff Council's Window Repair & Replacement in Conservation Areas explain the rules in more detail.
Getting an accurate quote
Send us a couple of photos of each window, inside and out, and tell us where you are. From that we can usually give you a price range straight away, then confirm it once we've seen the windows.
Useful photos show:
- the whole window from inside, with the sashes closed
- the sill and the bottom of the lower sash, close up
- anything that's broken, stuck or rotten
Please get in touch to discuss your project requirements.
Common questions
Can you repair just one window?
Yes.
How long does a full restoration take?
Around two days per window.
Will the windows be out overnight?
If the windows are being painted, we generally work on them at our workshop. The window boxes are boarded securely while we work on the windows.
Would you like a ballpark price for your windows?
Send us a few photos and your postcode. We'll tell you whether they can be saved and what it will cost.