Level of disruption*
Low
Medium
High
Retrofit costs
£15,000
Air source heat pump
External wall insulation
10,000
Double
glazing
With £7,500
government
grant
Internal wall
insulation
5,000
Draught proofing
Floor insulation
Cavity wall insulation
Annual CO2
savings
Loft insulation
0
0kg
1,000
2,000
3,000
Level of disruption*
Low
Medium
High
Retrofit costs
£15,000
Air source heat pump
External wall insulation
10,000
Double glazing
Internal wall insulation
With £7,500
government grant
5,000
Floor insulation
Cavity wall insulation
Draught proofing
Loft insulation
Annual CO2 savings
0
0kg
500
1,000
1,500
2,000
2,500
3,000