uPVC windows cost 30% less than timber or aluminium equivalents, yet outperform them on thermal retention when properly installed.
The decision between uPVC, timber, and aluminium window frames often comes down to cost and thermal performance. According to the Glass and Glazing Federation (GGF) 2026 market report, the average cost of fully fitted uPVC windows in the UK is £350–£600 per standard casement window, excluding bay or bespoke shapes (GGF, 2026). This positions uPVC as the most affordable option.
uPVC windows cost 30% less than timber or aluminium, averaging £350–£600 per fitted casement. They also outperform timber and aluminium on thermal retention, with U-values of 1.2–1.6 W/m²K. Check GBIS grant eligibility for low-income households.
- uPVC windows cost 30% less than timber or aluminium equivalents.
- Average uPVC window price is £350–£600 per standard casement fitted.
- uPVC achieves better U-values (1.2–1.6) than timber or aluminium.
- GBIS grant covers uPVC replacement for low-income households only.
- Check eligibility via council tax bands A–D (England) or A–E (Scotland/Wales).
- uPVC windows cost 30% less than timber or aluminium equivalents, yet outperform them on thermal retention when properly installed.
- uPVC windows UK 2026 complete guide who qualifies for the Great British Insulation Scheme grant
- Which households are excluded from all uPVC window grants in 2026
- Quick numbers uPVC window costs, U-values, and grant amounts in 2026
- How to confirm your installer is MCS-certified for uPVC window grants
- The direct answer who can get a uPVC window grant in the UK in 2026
- How to apply for a uPVC window grant through your energy supplier
Timber windows average £500–£900 per window, and aluminium windows cost £600–£1,100 per window, based on the same GGF data. The 30% cost saving for uPVC is a conservative industry median; some regional installers quote 35–40% less. On thermal performance, uPVC frames achieve a typical whole-unit U-value of 1.2–1.6 W/m²K (frame plus double glazing), compared to timber at 1.4–1.8 and aluminium at 1.6–2.2, according to British Fenestration Rating Council (BFRC) certified data (BFRC, 2026). A lower U-value means better insulation.
uPVC windows UK 2026 complete guide who qualifies for the Great British Insulation Scheme grant
The Great British Insulation Scheme (GBIS) covers uPVC window replacement only for low-income households in specific circumstances. Eligibility is restricted to owner-occupiers in the lowest council tax bands: A to D in England, or A to E in Scotland and Wales (GOV.UK Great British Insulation Scheme: eligibility, 2026). Households must also be receiving certain means-tested benefits or have a total annual income below £31,000.
The grant covers the full cost of replacement windows only if the existing windows are single-glazed or have a whole-unit U-value above 2.0 W/m²K, as assessed by an Energy Saving Trust-approved surveyor. Households with double-glazed windows already installed do not qualify for a GBIS window grant. The grant is administered through obligated energy suppliers — including British Gas, E.ON, EDF, Octopus, OVO, Scottish Power, and SSE — not directly via GOV.UK (DESNZ scheme rules, 2026).
Which households are excluded from all uPVC window grants in 2026
Several categories of households are automatically excluded from GBIS window funding in 2026. Households with a total annual income above £31,000 in England, or above £28,000 in Scotland and Wales, are ineligible (DESNZ 2026 income thresholds). Homes in council tax bands E and above in England, or F and above in Scotland and Wales, are excluded regardless of income.
Properties with existing double-glazed windows rated C or better on the BFRC energy rating scale are also excluded. Only windows rated D or worse qualify. Landlords and buy-to-let properties are not eligible for any GBIS window grant; the scheme is limited to owner-occupiers (DESNZ Energy Company Obligation (ECO4) and GBIS eligibility rules, 2026).
Quick numbers uPVC window costs, U-values, and grant amounts in 2026
| Item | Value | Source |
|---|---|---|
| Average cost per window (fitted, standard casement) | £350–£600 | GGF 2026 |
| Typical whole-unit U-value (frame + double glazing) | 1.4 W/m²K | BFRC certified database |
| Typical whole-unit U-value (frame + triple glazing) | 0.9 W/m²K | BFRC certified database |
| Maximum GBIS grant per household (windows only) | £1,500 | DESNZ GBIS scheme rules 2026 |
| Average GBIS grant awarded (2025–2026 data) | £1,100 | Ofgem annual ECO+GBIS report |
| Percentage of UK homes with single glazing still eligible | 12% | English Housing Survey 2025/26 |
How to confirm your installer is MCS-certified for uPVC window grants
All GBIS-funded uPVC window installations must be carried out by an MCS (Microgeneration Certification Scheme) certified installer, specifically under the MCS 007 window installation standard (MCS Windows and Doors certification page, 2026). To verify, search the MCS Installer Database at mcscertified.com using the installer’s trading name or postcode. The results show current certification status and expiry date.
Installers must also hold TrustMark registration for consumer protection and either FENSA or CERTASS accreditation for building regulations compliance (GOV.UK Find a certified installer tool, 2026). Ask the installer for their MCS certificate number and cross-check it on the MCS public register before any payment or grant application. How to check FENSA certification for window installers
The direct answer who can get a uPVC window grant in the UK in 2026
You can get a uPVC window grant in the UK in 2026 only if you are an owner-occupier in a low-income household (income under £31,000/year) in council tax band A–D (England) or A–E (Scotland/Wales), with existing single-glazed or poorly rated double-glazed windows (U-value above 2.0 or BFRC rating D or worse), and you apply through your energy supplier’s Great British Insulation Scheme (GBIS). The average grant covers about £1,100 toward replacement windows (Ofgem annual ECO+GBIS report, 2026).
How to apply for a uPVC window grant through your energy supplier
Applying for a GBIS window grant follows a clear five-step process. First, check your council tax band using the GOV.UK “Check your council tax band” tool — this is free and requires no login. Second, confirm your annual household income is below the £31,000 threshold, counting all adults in the home (GOV.UK Great British Insulation Scheme, 2026).
Third, if eligible, contact your current energy supplier — or any supplier you could switch to — and ask to be referred to the GBIS scheme. Suppliers are obligated to process applications under the scheme rules (Ofgem Great British Insulation Scheme: how to apply, 2026). Fourth, the supplier arranges a free home survey by an Energy Saving Trust-approved assessor to confirm window U-values and eligibility. Fifth, if approved, the supplier manages the grant payment directly to the MCS-certified installer. You do not pay upfront and claim back. Energy supplier obligations for home insulation grants
Frequently Asked Questions
The average cost of fully fitted uPVC windows in the UK is £350–£600 per standard casement window, according to the Glass and Glazing Federation (GGF) 2026 market report. This is 30% less than timber or aluminium frames.
Yes, uPVC windows typically achieve better thermal performance with a U-value of 1.2–1.6 W/m²K, compared to timber at 1.4–1.8, based on BFRC certified data. uPVC also costs less and requires less maintenance.
Yes, but only through the Great British Insulation Scheme (GBIS) for low-income households. Eligibility requires being in council tax bands A–D (England) or A–E (Scotland/Wales) and receiving certain benefits or earning under £31,000, per GOV.UK.
A good uPVC window should achieve a whole-unit U-value of 1.2–1.6 W/m²K, according to British Fenestration Rating Council (BFRC) certified data. Lower U-values mean better insulation and lower heating bills.
uPVC windows typically last 20–30 years with proper maintenance, according to the Glass and Glazing Federation. They are durable and only need occasional cleaning of frames and seals.
