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Sash windows · England

Triple glazed sash windows in Northamptonshire

Triple glazed sash windows across Northamptonshire: free survey, written fixed quote, and fitting by installation teams working for us. Towns we cover include Northampton, Corby and Daventry.

6Towns with local pages
EnglandRules applied
1.4U-value limit (W/m²K)
6 to 10 weeksTypical lead time
White vertical sliding sash windows on a Victorian London terrace

Victorian and Georgian looks with modern glass and locks. A sash window has one or two sashes that slide up and down in a box frame.

Guide prices across Northamptonshire

Small window

about 600 x 1000 mm (bathroom, landing)

£1,295 – £1,595inc VAT · £1,080 – £1,330 ex VAT

  • uPVC frame, triple glazed, warm-edge spacers
  • Removal and disposal of the old window
  • Fitted, sealed and made good inside and out
Typical size

Medium window

about 1200 x 1200 mm (bedroom)

£1,695 – £2,095inc VAT · £1,410 – £1,745 ex VAT

  • uPVC frame, triple glazed, warm-edge spacers
  • Removal and disposal of the old window
  • Fitted, sealed and made good inside and out

Large window

about 1800 x 1200 mm (lounge)

£2,595 – £3,195inc VAT · £2,160 – £2,660 ex VAT

  • uPVC frame, triple glazed, warm-edge spacers
  • Removal and disposal of the old window
  • Fitted, sealed and made good inside and out

Guide prices, supply and fit. The written quote after your survey fixes the price for the specification shown; anything extra is agreed with you first.

Towns in Northamptonshire

Rules in England

The rules for replacement windows in England are set by Approved Document L (2021 edition, with 2023 amendments): 1.4 W/m²K, or a Window Energy Rating of band B or better. Replacement windows are a controlled fitting. A competent person scheme installer (such as FENSA or Certass) self-certifies the work and notifies the council within 30 days; otherwise a building control body approves it.

Planning: Replacing windows on a house is normally permitted development if the new ones look similar. New upper-floor windows in a side wall must be obscure glazed and fixed, or open only above 1.7 m. Flats and maisonettes have no householder permitted development rights, so a change that alters their appearance needs planning permission. An Article 4 direction in a conservation area may mean permission is needed, and listed buildings need listed building consent.

How it works

The surveyor measures every opening, checks ventilation, escape windows and safety-glass zones, and talks through styles. Your written quote lists each item with its glass build-up and U-value, and the price is fixed for that specification.

  • Guide prices published, not hidden
  • No pressure: the quote is yours to keep
  • Frames, glass and fitting in one contract
  • Advice on planning and consents before you order

Questions

How much do triple glazed sash windows cost?

Our guide starts at £1,295 for a small uPVC sash, fitted and inc VAT. Timber sashes cost more; UK quotes for timber triple sashes run past £3,000 each.

Will triple glazing make my sashes heavy to lift?

The balances are sized for the sash weight, so they should slide smoothly. Heavier sashes use stronger balances or weights.

Can I keep my original sash boxes?

Sometimes. A timber specialist can fit new sashes into sound original boxes, but the glass thickness is limited by the sash depth.

Do you cover all of Northamptonshire?

We arrange surveys and fitting across Northamptonshire.

Do I need permission for triple glazed sash windows in England?

In England, like-for-like replacements on a house are normally permitted development; flats need permission if the change alters their appearance, Article 4 areas may need permission, and listed buildings need listed building consent.

Sash windows in nearby areas of England

Other products in Northamptonshire

Sash windows across Northamptonshire

Written quote fixed for the specification, after a free survey. Building Regulations sign-off by a competent person scheme installer or building control, as the law requires in England.

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