Letchworth Garden City · Hertfordshire
Sash Windows in Letchworth Garden City
Homeowners and landlords in Letchworth Garden City can get a written sash window quote that fixes the price for the joinery, glass, colour and hardware shown.
- SG6
- SG5
- SG15
- Guide from £1,495
About uPVC sliding sash windows in Letchworth Garden City
Sash window prices depend on size, timber or uPVC, whether you replace the whole frame or just the sashes, the glazing bar pattern, horns and mouldings, glass type and the paint colour. Listed or conservation work that needs matching details costs more. See the guide prices for typical ranges.
In England, Approved Document L allows an alternative where a window must keep a building's character: a centre-pane U-value no worse than 1.2 W/m²K, or single glazing supplemented by low-E secondary glazing. Otherwise a replacement should meet 1.4 W/m²K or Window Energy Rating band B.
Timber sash windows are usually made from engineered softwood or durable hardwoods, factory primed and finished with microporous paint that lets moisture escape. Factory finishing gives a more even coat than painting on site, but timber still needs periodic redecoration, and the interval depends on exposure and colour.
A sliding sash only opens to about half its frame height, which can make an escape window harder to achieve. In England, Approved Document B guidance calls for at least 0.33 m² clear opening, 450mm high and wide, so tilt-in or side-hung escape sashes are sometimes specified for upper floors.
Included as standard
- Removal of old sashes or frames and disposal
- Double glazed units, with safety glass where required
- Survey recording mouldings, horns, bars and box condition
- Sealing, finishing and written guarantee terms

Local details for Letchworth Garden City
- Postcodes covered
- SG6, SG5, SG15 and the surrounding area, including Hitchin, Stevenage and Luton
- Coast
- Letchworth Garden City is well inland, around 70 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Letchworth Garden City the midwinter sun reaches about 15° above the horizon at noon, with roughly 7.5 hours of daylight, rising to about 62° and 16.5 hours in midsummer. Glazing bars and deep frames reduce daylight, so slimmer bars and high light-transmission low-E glass help north-facing rooms. Tall south-facing sashes can let in strong summer sun; the top sash can be lowered to vent warm air out at high level.
- Access and setting
- Older rural houses often have sash openings that are out of square, with soft stone or lime plaster around them, so each window is measured individually and fitted gently. Exposed sites benefit from draught seals and robust weatherboards on the bottom sash.
- Rules in England
- Approved Document K requires safety glass in critical locations in England: glazing in doors and in side panels within 300 mm of a door, up to 1500 mm above floor level, and any glazing in walls or partitions up to 800 mm above floor level.
Guide prices in Letchworth Garden City
| Typical job | Guide price inc VAT |
|---|---|
| uPVC sliding sash, 900 × 1500 mm | £1,495 – £1,995 |
| Timber-effect uPVC sash, 900 × 1500 mm | £1,795 – £2,295 |
| Painted timber sash, 900 × 1500 mm | £2,595 – £3,295 |
Get a guide price for your size
Listed buildings in England need listed building consent for most changes to historic windows or glass, and conservation areas can restrict changes visible from the street. Speak to the council's conservation officer before ordering.
Specification choices
Heritage glass options
Slim double glazing, low-E coatings and textured glass that looks like old cylinder glass for sensitive elevations.
Spring-balanced timber sash
Timber sashes running on concealed spring balances, giving a slimmer frame where weight pockets are not needed or space is tight.
Timber box sash
Traditional weights, cords and pulleys in a box frame, made in engineered softwood or hardwood and factory painted to your colour.
Sash Windows in Letchworth Garden City: questions
What guarantee comes with new sash windows?
Manufacturer guarantees apply to the joinery, finish, sealed units and hardware, and the terms are confirmed in writing. Cover on the paint finish often depends on regular maintenance, so check the conditions. Guarantee terms for the installation are set out in writing with your quote, so you know what is covered before agreeing to go ahead.
How long does it take to replace sash windows?
Fitting a single sash window usually takes most of a day, longer where the box frame is removed or plaster disturbed. A whole house typically takes several days on site. The windows are made to order first, and timber sashes with special details take longer to manufacture; the lead time is confirmed in writing with your quote.
How much do sash windows cost?
The cost of sash windows depends on size, material, whether you replace the whole frame or only the sashes, the glazing bar pattern, the glass and the finishing details such as horns and mouldings. Timber usually costs more than uPVC, and listed building work costs more again. See the guide prices for typical ranges; the written quote fixes your price.
Are uPVC sash windows allowed in conservation areas?
It depends on the council. Some conservation areas and Article 4 directions require timber on front elevations, while others accept well-detailed uPVC sashes with sculpted profiles and run-through horns. Listed buildings almost always need timber. Check your council's guidance or ask the planning department before choosing uPVC, because removing unauthorised windows later is costly.
Do you cover Letchworth Garden City for sash windows?
Yes. We can quote for sash windows across Letchworth Garden City and the surrounding Hertfordshire area, including postcode districts SG6, SG5 and SG15, and nearby Hitchin, Stevenage and Luton. Start with your postcode on the quote form and a glazier will arrange a free survey before giving you a written quote.
More glazing in Letchworth Garden City
Get a written quote in Letchworth Garden City
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.