Casement windows · Hertfordshire
Triple glazed casement windows in Stevenage
Looking at triple glazed casement windows for a home in Stevenage? We survey, quote and fit across Hertfordshire, and the SG1 postcode district is part of that.

Side- and top-hung sashes with hinges sized for heavier glass. A casement window has sashes hinged at the side or top that open outwards, the most common window style in UK homes.
Winter light and glass choice in Stevenage
On the shortest day, Stevenage gets about 7 h 46 min of daylight and the midday sun reaches only about 15° above the horizon. Low winter sun means north-facing rooms here gain little solar heat, which is where triple glazing’s lower heat loss helps most.
Guide prices in Stevenage
| Guide | Supply and fit, inc VAT |
|---|---|
| Small window about 600 x 1000 mm (bathroom, landing) | £695 – £845 |
| Medium window about 1200 x 1200 mm (bedroom) | £895 – £1,095 |
| Large window about 1800 x 1200 mm (lounge) | £1,395 – £1,695 |
Guide prices. Your written quote after the free survey fixes the price for the specification shown.
Rules for casement windows in England
In England, replacement windows must meet 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.
Before ordering: 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
After the free survey you get a written quote naming the frame system, the glass build-up and the whole-window U-value for every item. Windows are made to order, then fitted, sealed and made good, one opening at a time.
- 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 from Stevenage
Can my existing casement layout stay the same?
Yes. We match the existing layout unless you ask for a change, which can matter for planning in conservation areas.
Are triple glazed casements harder to open?
They are a little heavier, but with correctly sized hinges they open and close smoothly.
Do you fit triple glazed casement windows in Stevenage?
Yes. We arrange surveys and fitting in Stevenage and across Hertfordshire. Send your postcode and the windows or doors you want replaced, and we will book a free survey.
Do I need permission for triple glazed casement windows in Stevenage?
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. Check whether your street is in a conservation area or covered by an Article 4 direction before changing the style.
Nearby
Nearby towns on our list include Hitchin (8 km), Letchworth Garden City (9 km), Welwyn Garden City (11 km) and Harpenden (14 km).
Other products in Stevenage
- uPVC windows
- Aluminium windows
- Timber windows
- Alu-clad timber windows
- Flush casement windows
- Tilt and turn windows
- Sash windows
- Bay and bow windows
- Fixed and picture windows
- Composite front doors
- French doors
- Sliding patio doors
- Bifold doors
- Glass-only replacement
- Acoustic triple glazing
- Security glazing
- Whole-house replacement
- New builds and self-builds
- Period homes and conservation areas
- Flats and apartments
- Passivhaus and EnerPHit
Casement windows in Stevenage: book your free survey
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.
