Insulation Savings Calculator
See how much each type of insulation could save you based on your home type and current insulation levels.
Select your house type and tick the insulation measures you already have. The calculator will show the cost, annual savings, and payback period for each missing measure — plus which ones qualify for government grants.
What do you already have?
Potential annual saving
£835
Estimated total cost
£8,550
Grants available for
2 measures
Top up or install loft insulation to the recommended 270mm depth
Install cost
£400 – £700
Annual saving
£200 – £300
Payback
~2.2 yrs
ECO4 / GBIS may fully fund loft insulation
Fill the gap in cavity walls to stop heat escaping through the walls
Install cost
£600 – £1,000
Annual saving
£250 – £400
Payback
~2.5 yrs
ECO4 / GBIS may cover full cost if eligible
Replace single-glazed windows with double or triple glazing
Install cost
£4,000 – £9,000
Annual saving
£140 – £220
Payback
~36.1 yrs
Insulate suspended timber floors to reduce draughts and heat loss
Install cost
£500 – £900
Annual saving
£60 – £100
Payback
~8.8 yrs
* Savings based on Energy Saving Trust data at current Ofgem price cap rates. Costs are typical UK market rates — get 3 quotes for accurate pricing. Payback uses mid-range estimates.