What a sash window costs in 2026
A sliding sash window is the classic vertical-opening window of Victorian, Georgian and Edwardian homes, with one or two panels (the sashes) that slide up and down. It is more expensive than a casement because there is far more to it: two moving sashes, a balance mechanism, deeper boxes and a lot more joinery. In the calculator above, switch the style to Sash and you will see the per-window figure jump accordingly. A uPVC sliding sash costs £700 to £1,500 fully fitted in 2026, with a typical figure around £1,050. A timber heritage sash, the kind specified for period and conservation work, runs to roughly £1,950 fitted per window.
The material decision matters more for sashes than for any other style, because the look is the whole point. uPVC sash windows are now made to mimic the slim profiles, run-through horns and glazing bars of a real box sash, at around half the price of timber and with no painting to do. Timber, on the other hand, is the only option many planning authorities will accept on a listed building. If you are weighing up the styles before you price them, our guide to sash windows explained covers the box sash, spiral balance and spring balance options in full.
| Sash window | Low | Typical | High |
|---|---|---|---|
| uPVC sliding sash | £700 | £1,050 | £1,500 |
| Timber sash (heritage) | – | ~£1,950 | – |
Source: DGCC 2026 consensus (uPVC sash, Checkatrade) and Best Buys list (timber heritage sash ~£1,950). uPVC sash is the value pick where planning allows it.
uPVC sash or timber sash
For most homes outside a conservation area, a uPVC sliding sash is the sensible choice. At £700 to £1,500 it costs roughly half what timber does, it needs no repainting, and a good one is hard to tell from the real thing at street level. It also lasts 20 to 25 years with no upkeep beyond the odd seal check.
Timber earns its premium only where the look or the rules demand it. A heritage timber sash at around £1,950 can last 60 years if it is maintained, but that maintenance means repainting every 8 to 10 years. If your home is listed or sits in a strict conservation area, timber may be the only option you are allowed, so check before you fall in love with the cheaper quote. If you want to price a like-for-like timber figure, the timber window calculator runs the same sums on a timber frame, and the uPVC window calculator does the same for the value option. For the simplest hinged alternative on a non-period home, see the aluminium window calculator too.
The verdict on sash windows
Sash windows cost more than casements whichever material you pick, so the honest answer depends entirely on your home. A uPVC sash is a clear Best Buy where planning allows it. A timber heritage sash is only worth the extra on a period or conservation property where nothing else will do.
It depends Sash windows: it depends. uPVC sash is the value pick; timber heritage sash is for period homes only.
I fit a lot of uPVC sashes in Victorian terraces where the council is relaxed, and honestly, once they are in, neighbours cannot tell. Save the timber budget for the front elevation of a listed house, where you have no choice. Paying £1,950 a window for the back of the house, where nobody looks, is money you will not get back.
Tom Bradley, FENSA-registered installer
Frequently asked questions
A uPVC sliding sash window costs £700 to £1,500 fully fitted in 2026, with a typical figure around £1,050. A timber heritage sash for a period or conservation-area home runs higher, at roughly £1,950 fitted per window.
A sash window has two moving panels, a balance mechanism and far more joinery than a simple casement, so it costs more to make and takes longer to fit. That is why a uPVC sash at £700 to £1,500 sits well above a uPVC casement at £400 to £1,000.
Yes. Modern uPVC sliding sash windows are made to mimic the slim profiles, run-through horns and astragal bars of a traditional box sash, at roughly half the cost of timber. They are a sensible choice anywhere that is not a listed building or strict conservation area.
Often not. Listed buildings and many conservation areas require timber sashes to preserve the original appearance, so always check with your local planning authority before ordering. Where uPVC is allowed, it is the cheaper and lower-maintenance option.