Retrofit Savings Estimator
Estimate the combined savings from multiple energy efficiency improvements (insulation, windows, heating, etc).
Retrofit Savings Estimator
Current Annual Cost
£1800.00
Total Investment
£34800.00
Annual Saving
£2304.00
Payback Period
15.1
years
EPC Rating
Quick Win (3 measures)
Loft Insulation to 270mm
highLay 270mm mineral wool in loft
Cost
£500.00
Annual Saving
£216.00
Payback
5 yrs
EPC Gain
+12
ROI
43%
Cavity Wall Insulation
highFill cavity walls with foam or mineral wool
Cost
£1200.00
Annual Saving
£270.00
Payback
8 yrs
EPC Gain
+15
ROI
23%
Smart Heating Controls
mediumInstall smart thermostat with TRVs on all radiators
Cost
£600.00
Annual Saving
£108.00
Payback
10 yrs
EPC Gain
+5
ROI
18%
Major Upgrade (2 measures)
Air Source Heat Pump
very-highReplace boiler with ASHP (COP 3.2). Needs BUS grant consideration.
Cost
£10000.00
Annual Saving
£720.00
Payback
25 yrs
EPC Gain
+25
ROI
7%
5kW Solar Panel System
very-highInstall 5kW solar PV system with grid export
Cost
£10000.00
Annual Saving
£630.00
Payback
29 yrs
EPC Gain
+15
ROI
6%
Medium Investment (2 measures)
High-Efficiency Gas Boiler
mediumReplace old boiler with modern condensing boiler (90%+ efficiency)
Cost
£2500.00
Annual Saving
£144.00
Payback
31 yrs
EPC Gain
+8
ROI
6%
Double Glazing Upgrade
mediumReplace single/old double glazing with modern double glazing
Cost
£5000.00
Annual Saving
£126.00
Payback
71 yrs
EPC Gain
+10
ROI
3%
Premium Addition (1 measures)
5kWh Battery Storage
lowAdds to solar: increases self-consumption, enables backup power
Cost
£5000.00
Annual Saving
£90.00
Payback
100 yrs
EPC Gain
+0
ROI
2%
Do These First
- ▸Loft Insulation to 270mm
5 yr payback, £216.00/yr saving - ▸Cavity Wall Insulation
8 yr payback, £270.00/yr saving - ▸Smart Heating Controls
10 yr payback, £108.00/yr saving
Medium-Term
- ▪Air Source Heat Pump
25 yr payback, £720.00/yr saving - ▪5kW Solar Panel System
29 yr payback, £630.00/yr saving - ▪High-Efficiency Gas Boiler
31 yr payback, £144.00/yr saving
Long-Term Investment
- ●Double Glazing Upgrade
71 yr payback, £126.00/yr saving - ●5kWh Battery Storage
100 yr payback, £90.00/yr saving
EPC Rating Impact
Current Rating
39
out of 100
After All Upgrades
100
+90 points
💡 Retrofit Strategy
- Start with quick wins: Loft insulation, cavity fill, controls have best payback
- Apply for grants: Check BUS grant (£7,500 for heat pump), ECO grants, council funding
- Combine measures: Installing together is cheaper and more effective
- Improve insulation first: Before installing heat pump or solar
- Phase the work: Don't need to do everything at once
- Get professional advice: EPC assessor can prioritize for your property
- Plan for the future: Gas boilers will be phased out by 2035
- Consider package financing: Many installers offer payment plans
Ranked by Return on Investment (ROI)
Loft Insulation to 270mm
£500.00 cost, £216.00/year saving
43% ROI
5 yr payback
Cavity Wall Insulation
£1200.00 cost, £270.00/year saving
23% ROI
8 yr payback
Smart Heating Controls
£600.00 cost, £108.00/year saving
18% ROI
10 yr payback
Air Source Heat Pump
£10000.00 cost, £720.00/year saving
7% ROI
25 yr payback
5kW Solar Panel System
£10000.00 cost, £630.00/year saving
6% ROI
29 yr payback
High-Efficiency Gas Boiler
£2500.00 cost, £144.00/year saving
6% ROI
31 yr payback
Related Tools
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EPC Improvement Checker
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Insulation Savings Calculator
🏠 Home & PropertyCalculate how much you'll save by adding loft insulation, wall insulation, or pipe insulation to your home.
Double Glazing Payback Calculator
🏠 Home & PropertyFind out if upgrading to triple glazing or replacing single glazing with double glazing will pay for itself.