Kettering · Northamptonshire
Sash Windows in Kettering
Our glaziers survey sash windows across Kettering, recording mouldings, horns and glazing bars so the new windows suit the house and any conservation requirements.
- NN15
- NN16
- Guide from £1,495
About double glazed sash windows in Kettering
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.
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.
Many Victorian and Georgian sashes reach low to the floor. In England, Approved Document K treats glazing within 800mm of floor level as a critical location, so the lower panes of tall sash windows usually need toughened or laminated safety glass, which should be permanently marked.
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.
What's included
- Double glazed units, with safety glass where required
- Survey recording mouldings, horns, bars and box condition
- Made-to-measure timber or uPVC sash windows
- Sealing, finishing and written guarantee terms

About Kettering for this job
- Postcodes covered
- NN15, NN16 and the surrounding area, including Wellingborough, Corby and Rushden
- Coast
- Kettering is well inland, around 76 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Kettering the midwinter sun reaches about 14° above the horizon at noon, with roughly 7.4 hours of daylight, rising to about 61° and 16.6 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 Kettering
| 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
In England, replacing a whole window, roof window or glazed external door is building work. It has to be notified to building control, either by an installer registered with a competent person scheme such as FENSA or Certass, or through a building notice to the council. Replacing only the glass in an existing frame is a repair and is not notifiable.
Choosing your sash windows
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.
Glazing bar patterns
Two over two, six over six or other bar layouts, as true divisions or bars bonded to the glass faces.
uPVC sliding sash
Low-maintenance uPVC frames with sculpted profiles and optional woodgrain foils, suited to homes where planning rules allow uPVC.
Sash Windows in Kettering: questions
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.
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.
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.
Can I have double glazed sash windows in a listed building?
Sometimes, but listed building consent is needed for significant works, and some councils will only accept repair of the original windows or slim double glazing with matching details. Secondary glazing is often accepted where new windows are not. Speak to your council's conservation officer before ordering; we can provide drawings and specifications to support an application.
Do you cover Kettering for sash windows?
Yes. We can quote for sash windows across Kettering and the surrounding Northamptonshire area, including postcode districts NN15 and NN16, and nearby Wellingborough, Corby and Rushden. Start with your postcode on the quote form and a glazier will arrange a free survey before giving you a written quote.
Get a written quote in Kettering
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.