Windows & Glazing
Why are windows and doors so expensive?
A typical uPVC window costs £350–£700 installed due to Building Regulations Part L. See what drives the price and how to cut costs.
Windows & Glazing
Expert guides on double glazing, triple glazing, window types, costs, and energy ratings for UK homeowners. Find out which windows save the most energy and money.
452 articles
Latest Windows & Glazing Articles
Windows & Glazing
Why are my double glazed windows covered in condensation?
A failed edge seal lets damp air into the insulated gap, causing mist you cannot wipe away. Replacement costs £150–£300 per window in 2026.
Windows & Glazing
Why are double glazed windows wet on outside?
External condensation on double glazing means your windows are working efficiently, cutting heat loss by 50%. Learn what causes it and when to worry.
Windows & Glazing
Why are double glazed windows good insulators?
Double glazed windows cut heat loss by up to 50% vs single glazing. Argon gas fills and low-E coatings bring U-values down to 1.4 W/m²K in UK homes.
Windows & Glazing
Why are double glazed windows filled with argon?
Double glazed windows are filled with argon to reduce heat loss by roughly 30%. Learn how this inert gas improves thermal efficiency and lowers energy bills.
Windows & Glazing
Why aluminium windows and doors?
Aluminium windows and doors last 45+ years, achieve U-values of 1.2 W/m²K, and outperform uPVC and timber for UK homes. Here is what the data shows.
Windows & Glazing
Who makes doors and windows?
Everest, Anglian and Safestyle make most UK uPVC and aluminium frames. Find out which brands lead the market and when to use a local joinery workshop instead.
Windows & Glazing
Which double glazing company is best UK?
Everest scored 89% in a 2026 Which? survey of 3,000 homeowners. Compare FENSA-registered quotes from top UK double glazing companies to cut costs.
Windows & Glazing
Which double glazing company?
No single installer suits every home. Compare FENSA and TrustMark registered double glazing companies to stay compliant and get the best price from three quotes.
Windows & Glazing
Which double glazed windows are the best?
A-rated double glazed windows with a U-value below 1.2 W/m²K cut bills by £195 a year in a semi-detached home. Compare frame types and costs here.
Windows & Glazing
Where can I buy windows and doors?
FENSA-registered installers must meet 2026 Building Regulations. National brands cost £3,500–£6,000 for three windows; local firms charge 20–30% less.
Windows & Glazing
When was double glazing invented?
The first sealed double-glazing patent was filed in 1865 by Thomas Stetson, with UK installation following in the 1870s. Here is the full history.
Windows & Glazing
When was double glazing?
Double glazing arrived commercially in the UK in the 1970s, with mass adoption from the 1980s. By 2026, 90% of UK homes have it fitted.
Windows & Glazing
When should windows and doors be replaced?
Replace windows and doors when they are over 20 years old, draughty, or show condensation. Upgrading can cut heat loss by up to 40%. Check your options now.
Windows & Glazing
When did double glazed windows come out?
Double glazing first sold commercially in the UK around 1974, but only 5% of homes had it by the late 1970s. Here's the full timeline to widespread adoption.
Windows & Glazing
What windows and doors qualify for tax credit?
Glazing is standard-rated for VAT at 20%. The zero rate for energy-saving materials covers insulation, heat pumps and solar panels; HMRC names secondary and double glazing as excluded (VAT Notice…
Windows & Glazing
What thickness is double glazed windows?
Most UK double glazed units are 24–28 mm thick, using two 4 mm panes and a 12–16 mm cavity. Find out how to measure yours before ordering replacements.
Windows & Glazing
What is the windows and doors scheme?
The UK Windows and Doors Scheme offers up to £7,500 to replace single glazing in EPC-rated D–G homes. See if you qualify for a free installation in 2026.
Windows & Glazing
What is the gap between double glazing?
The gap between double glazing is typically 16mm, achieving a U-value of 1.2 W/m²K and saving homeowners £195 a year on heating bills.
Windows & Glazing
What is mi windows and doors?
MI Windows and Doors are UK-made uPVC and aluminium units meeting 2026 Part L. A-rated models can cut heating bills by up to £165 a year.
Windows & Glazing
What is double glazing glass?
Double glazing uses two glass panes with an argon gap to cut heat loss. The Energy Saving Trust says it saves £195/year on energy bills for a semi-detached home.
Windows & Glazing
What is double glazed glass windows?
Double glazed windows use two glass panes filled with argon gas to cut heat loss by 50%. Typical UK savings reach £195 a year on energy bills.
Windows & Glazing
What is double glazed aluminium windows?
Double glazed aluminium windows use a thermal break frame and two glass panes to cut heating bills by up to £195 a year. Here is how they work and what…
Windows & Glazing
What industry is windows and doors?
Windows and doors belong to the fenestration industry, worth £8 billion a year in the UK and employing over 200,000 people. Here is what that means for you.
Windows & Glazing Glossary
Windows & Glazing FAQ
A full house of uPVC double glazed windows typically costs between 4,000 and 8,000 pounds for a three-bedroom semi-detached house. Individual windows range from 300 to 800 pounds depending on size and opening style. Prices include supply, fitting, and building regulations certification.
Triple glazing costs around 20 to 30 percent more than double glazing but delivers a U-value of around 0.8 compared to 1.2 for standard double glazing. The energy savings are modest for most UK homes, making it most worthwhile for north-facing rooms, noisy locations, or new builds where the price premium is smaller.
Most window replacements fall under permitted development and do not need planning permission. However, if your home is a listed building or in a conservation area, you will likely need consent. The installer must be FENSA registered or you will need separate building control sign-off.
Modern double glazed sealed units typically last 20 to 25 years. uPVC frames can last 25 to 35 years with minimal maintenance. Signs that replacement is needed include misting between panes, draughts around seals, difficulty opening or closing, and visible frame deterioration.
No UK scheme funds replacement windows on their own. The Great British Insulation Scheme closed on 31 March 2026 and only ever covered insulation, never glazing. ECO4 runs to 31 December 2026 in Great Britain only and targets insulation and heating for households on qualifying benefits; glazing is included only where it forms part of a wider whole-house retrofit. Glazing is also standard-rated for VAT at 20%, as HMRC lists double and secondary glazing as excluded from the energy-saving materials zero rate.
You may also like
Windows & Glazing
Triple glazing vs double glazing UK (2026)
Triple glazing achieves U-values of 0.8 W/m²K compared to 1.4 W/m²K for double glazing, saving UK homeowners an additional £30-50 per year in heating costs while providing superior noise reduction…
Windows & Glazing
New windows cost UK (2026)
New windows in the UK cost £300-£1,200 per window depending on material and specification. A full house replacement for a three-bedroom semi ranges from £3,500 to £7,500 for uPVC double…
Windows & Glazing
Is Secondary Glazing Worth It for a Victorian Terraced House?
Secondary glazing is generally worth it for a Victorian terraced house, particularly where conservation area rules prevent sash window replacement. Fitted internally without altering the building's exterior, it can reduce…
Windows & Glazing
Low E glass windows UK – are they worth it (2026)
Low E glass windows are worth it for UK homeowners because the invisible metallic coating significantly reduces heat loss through the glass, helping homes meet Building Regulations under Part L…
Windows & Glazing
Window security ratings for UK homes
Window security ratings in the UK are primarily defined by PAS 24, a British Standards Institution specification requiring windows to pass independent forced-entry testing, and Secured by Design, a police-backed…
Windows & Glazing
Double glazed windows misting up inside, causes and fixes
Double glazed windows mist up inside when the hermetic seal around the unit fails, allowing humid air to enter the gap between the panes where it condenses. This is a…