Energy prices have stayed stubbornly high through 2025 and 2026, making energy-efficient glazing one of the strongest home investments available. But how much will you actually save? It depends on your starting point, your home, and your specification.
Starting points
From single glazing to A-rated double glazing: typical heat loss through windows drops by 70-80%, saving £350-£600 per year on a typical 3-bed semi at 2026 energy prices. From 1990s-era D/E-rated double glazing to A++ rated: drop of 35-50%, saving £180-£320 per year. From A-rated to A++ rated or triple glazed: drop of 15-25%, saving £80-£150 per year.
The role of frame material
Frame material matters as much as glass. Whole-window U-value (including frame and seals) is what counts. Modern uPVC frames typically add 0.2-0.4 to the glass U-value; aluminium thermally-broken frames add 0.3-0.5; timber frames add 0.2-0.3. Always look at whole-window U-values, not just centre-of-glass figures.
Payback periods
Full-house re-glazing typically costs £6,000-£12,000 for a 3-bed semi. At current energy savings of £400-£600 per year, payback comes in 10-15 years. Properties with high heating bills (Victorian terraces, large detached houses, electrically heated flats) see payback in as little as 7-9 years.
Non-energy benefits
Energy savings alone don't justify the investment for many households — but combined with reduced noise, eliminated condensation, improved security, and a £4,000-£8,000 boost to property value, the case becomes much stronger.
Get a free energy assessment
We provide free U-value assessments and energy-saving projections for any UK property. Call 0800 088 6341 or request a survey online.
Need help with your glazing project? S&K Glazing offers free surveys and fixed-price quotes across the UK. Call 0800 088 6341, message us on WhatsApp at 07830 175306, or request a quote online.