Will Secondary Glazing Actually Pay for Itself?
Let's do the maths on energy savings, payback time, and whether it's actually worth doing
The Bottom Line
Energy Savings
£200-£400
Annual heating bill reduction
Payback Period
10-14 years
Time to break even
Property Value
+1-3%
Average increase
Let's Break It Down Properly
Typical 3-Bedroom House (10 Windows)
Initial Investment
Secondary glazing installation (10 windows)£3,500
Annual Benefits
Energy bill savings (25% reduction)+£300
Reduced condensation (less maintenance)+£50
Total Annual Savings£350
Payback Calculation
£3,500 ÷ £350 per year10 years
Property Value Increase
Average UK house value: £280,000
2% increase from improved EPC rating+£5,600
20-Year Total Return
Energy savings (20 years × £350)£7,000
Property value increase£5,600
Total Value Created£12,600
Net Profit (minus £3,500 cost)£9,100
What'll Make It More (or Less) Worth It
You'll Save More If:
- • You've still got single glazing (common in older homes)
- • Your walls and roof could do with more insulation too
- • You're on expensive heating (oil or electric especially)
- • You've got big windows or high ceilings (heat just flies out)
- • You live in a listed building (not many other options)
Maybe Not So Worth It If:
- • You've already got decent double glazing
- • Everything else is well-insulated already
- • You don't use much heating anyway
- • Small windows (less surface area = less benefit)
Calculate Your Personal ROI
Use our cost calculator to see exact savings for your home
Start Calculating