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You could be losing up to a quarter of your heating costs—literally—through outdated windows.
For years, replacing windows has often felt like a “luxury” home improvement to tackle later. But research shows that old glazing could quietly be costing you hundreds of pounds every year.
With energy prices still unpredictable, delaying upgrades may end up being far more expensive in the long term.
Homeowners Are Shifting Priorities
The latest annual survey from the National Self Build & Renovation Centre (NSBRC) highlights a major change in what homeowners are focusing on:
- 92% are budgeting for higher levels of insulation
- 71% have set aside funds specifically for triple glazing
Energy efficiency isn’t just a “nice to have” anymore—it’s becoming essential.
How Much Are Outdated Windows Costing You?
Calculations show just how much households could be losing due to inefficient windows:
| Property Type | Avg. Annual Energy Bill¹ | Est. Heat Loss via Windows² | Annual Window Waste (£)² | Modern Upgrade Saving³ |
| Flat / Apartment | £1,250 | 18% | £225 | £135/yr |
| Semi-Detached | £1,758 | 20% | £351 | £192/yr |
| Detached House | £2,450 | 25% | £612 | £435/yr |
If you live in a detached house, you could be losing up to 25% of your home’s heat, which adds up to over £600 a year. Upgrading to modern windows could save £435 annually.
Even if you live in a flat or apartment, nearly a fifth of your heat (18%) could be slipping away. Over a decade, that could mean thousands of pounds disappearing through old glazing.
Why Waiting Could Cost More
Even with the energy price cap set to fall next quarter, it’s not worth putting off improvements.
Jo Trotman, Sales and Marketing Manager, explains:
“Upgrading your windows will always save money in the long run. While the cap may decrease next quarter, there’s no guarantee prices will continue to fall.
It’s staggering how much heat—and therefore money—is lost through windows that don’t meet modern standards. Upgrading doesn’t just reduce monthly bills; it also future-proofs your home and can make it more attractive if you decide to sell.”
If you’re planning home renovations, upgrading your windows should be near the top of the list. Modern windows don’t just cut energy bills—they protect your property value, reduce exposure to future price hikes, and can pay for themselves over time.
@residencecollection
