How Much Does Double Glazing Cost in the UK?

Average Double Glazing Cost UK 2026

A standard double-glazed casement window costs £400–£900 supplied and fitted. A full house of 10 windows costs £4,000–£9,000. uPVC is the most affordable, aluminium and timber more expensive. Triple glazing costs 20–40% more than double.

Cost by Window Type

Standard casement window: £400–£900. Bay window: £1,200–£3,500. Sash window: £800–£1,800. Roof window (Velux style): £600–£1,200. Tilt and turn: £500–£1,000. French doors (pair): £1,500–£3,000. Bifold doors (3 panels): £3,000–£6,000. Composite front door: £1,000–£2,500.

uPVC vs Aluminium vs Timber

uPVC: most affordable, low maintenance, wide colour range, good energy efficiency. Aluminium: slimmer profiles, more contemporary look, 30–50% more expensive than uPVC. Timber: traditional look, most expensive to buy and maintain, preferred for period properties and conservation areas.

What Affects the Price

Frame material (uPVC/aluminium/timber), glass specification (double vs triple, glass type), window style and size, number of windows, installation complexity, and company. Always get at least 3 quotes — double glazing prices vary enormously between companies.

Energy Ratings and Savings

Windows are rated A++ to E for energy efficiency. A-rated or above windows are recommended for maximum energy savings. Upgrading from single glazed to A-rated double glazing saves approximately £110–£170 per year on energy bills for a typical semi-detached house.

Getting the Best Deal

Get at least 3 quotes. Be wary of inflated 'original prices' and huge discounts — this is a common sales tactic. Ask for the WER (Window Energy Rating) of the glass specification. Look for FENSA-registered companies as they self-certify building regulations compliance.