Solar panels, heat pumps and insulation in Bradford on Avon No 1 conservation area
In the Bradford on Avon No 1 conservation area (Wiltshire), external wall insulation needs planning permission, and so does an air source heat pump on a wall or roof facing the road; one at the back or side, internal and loft insulation and solar panels on a roof slope normally do not. The area has 300 listed buildings; on a listed building solar panels and heat pumps are not permitted development at all and need planning permission and listed building consent. 1,156 homes inside the boundary have an energy certificate: 48.7% are solid-wall homes with no wall insulation, 70.5% heat with a gas boiler and 57.7% are rated D–G; 96 have a heat pump. EPC register November 2026; rules as at 21 October 2026.
Data: EPC register November 2026 (latest certificate per home), conservation area boundaries 3 November 2026, permitted development rules as at 21 October 2026 · calculated 5 November 2026 · Methodology and sources
1,156homes with an energy certificate
48.7%solid walls, no insulation
70.5%heated by a gas boiler
96heat pumps
Article 4: Wiltshire publishes its Article 4 areas on planning.data.gov.uk and none overlaps this area; a direction can still exist on paper, so check with the council.
What needs planning permission in Bradford on Avon No 1
Work (house, not listed)
In a conservation area
Rule
Air source heat pump on a wall or roof facing the road, or nearer the road than the house
Planning permission needed
Part 14 Class G, G.1(j)
Air source heat pump at the back or side (outdoor unit up to 1.5 m³, MCS Planning Standards, one per house — two on a detached house)
No permission needed (permitted development)
Part 14 Class G
Solar panels on a pitched roof (up to 0.2 m proud, not above the ridge)
No permission needed (permitted development)
Part 14 Class A, A.2(c)
Solar panels on a wall, balcony or roof enclosure facing the road
Planning permission needed
Part 14 Class A, A.2(e)
Solar panels on a flat roof (up to 0.6 m above the roof)
Replacement windows and doors of similar appearance
No permission needed (permitted development)
Part 1 Class A, A.3(a)
Listed buildings: 300 in the area (grade I: 7, II*: 28). The table is for houses that are not listed: on a listed building, solar panels and air source heat pumps are not permitted development at all (they need planning permission), and any of these works needs listed building consent.
Flats: 39% of the certified homes here are flats or maisonettes. Homes in a block of flats have no householder rights for alterations; heat pumps and solar have their own, tighter rules for blocks of flats.
The homes in the area (latest certificate per home, n = 1,156)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
563
48.7%
Cavity wall, insulated (as built or unspecified)
240
20.8%
Modern wall (U-value from the design)
180
15.6%
Solid wall, insulated
49
4.2%
Cavity wall, filled
39
3.4%
Timber frame
31
2.7%
Solid wall, internal insulation
23
2.0%
Cavity wall, unfilled
16
1.4%
Cavity wall, partly insulated
10
0.9%
Solid wall, partly insulated
5
0.4%
Heating
Homes
Share
Gas boiler
815
70.5%
Electric (storage heaters, panels, boiler)
237
20.5%
Heat pump
96
8.3%
Communal heating
2
0.2%
LPG
2
0.2%
Oil
2
0.2%
Solid fuel (wood, coal)
2
0.2%
Loft / roof insulation
Homes
Share
No insulation
129
11.2%
Under 200 mm
213
18.4%
200 mm or more
238
20.6%
Insulated (depth not recorded)
198
17.1%
Flat or other home above
256
22.1%
Other
122
10.6%
Windows
Homes
Share
Double glazed
869
75.2%
Single glazed
191
16.5%
Secondary glazing
83
7.2%
Triple glazed
13
1.1%
BCDE
Energy rating: A 1 (0.1%) · B 175 (15.1%) · C 313 (27.1%) · D 410 (35.5%) · E 199 (17.2%) · F 51 (4.4%) · G 7 (0.6%). Houses and bungalows: 61% of the homes; solar panels on 0.4% of the certificates. Most common build period on the certificates: before 1900. Designated: 1 January 1969.
Compared with Wiltshire and England
Share of homes
Bradford on Avon No 1
All 244 areas in Wiltshire
England
Solid walls, no insulation
48.7%
42.5%
48.7%
Gas boiler
70.5%
45.5%
66.4%
Rated D–G
57.7%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 48% of these are from 2020 or later (latest 27 October 2026). “No insulation (assumed)” is the assessor's default for older walls.
The rules are England's national permitted development rules (General Permitted Development Order 2015, Schedule 2, as at 21 October 2026). They do not cover building regulations or a council's own conditions. This is not a planning decision: ask Wiltshire if in doubt.
Boundary: Wiltshire Council via planning.data.gov.uk (entity 44015331, reference CA/W/31, 89.4 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.