Casement windows · Northumberland
Triple glazed casement windows in Alnwick
Triple glazed casement windows for homes in Alnwick: measured on a free survey, made to order and fitted by installation teams working for us across Northumberland.

Like-for-like replacement for most post-war homes. 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 Alnwick
By midsummer Alnwick has about 17 h 28 min of daylight, but in December only around 7 h 05 min, with the noon sun at about 11°. Triple glazing keeps more heat in during those long, dark months; big south and west windows may suit solar-control glass for summer.
Guide prices in Alnwick
| 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
England requires replacement windows to achieve 1.4 W/m²K, or a Window Energy Rating of band B or better, which good triple glazing passes comfortably. 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
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 Alnwick
Do casement windows need trickle vents?
If the old windows had them, yes, and at least as large. If not, ventilation must be no worse than before. We size this on survey.
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.
Do you fit triple glazed casement windows in Alnwick?
Yes. We arrange surveys and fitting in Alnwick and across Northumberland. 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 Alnwick?
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
Also near Alnwick: Morpeth (27 km), Ashington (28 km), Bedlington (32 km) and Blyth (34 km).
Other products in Alnwick
- 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 Alnwick: 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.
