Solar panels, heat pumps and insulation in Sherborne 1 conservation area
In the Sherborne 1 conservation area (Dorset), 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. An Article 4 direction published by Dorset covers part of this area (about 2% of it), but the published data does not say which rights it removes — check the direction before any work. The area has 341 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. 771 homes inside the boundary have an energy certificate: 50.7% are solid-wall homes with no wall insulation, 82.4% heat with a gas boiler and 64.7% are rated D–G; 0 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
771homes with an energy certificate
50.7%solid walls, no insulation
82.4%heated by a gas boiler
0heat pumps
Article 4: An Article 4 direction published by Dorset covers part of this area (about 2% of it), but the published data does not say which rights it removes — check the direction before any work. (Sherbourne Area 2)
What needs planning permission in Sherborne 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), unless an Article 4 direction removes it — check with the council
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), unless an Article 4 direction removes it — check with the council
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)
Prior approval of appearance from the council, unless an Article 4 direction removes it — check with the council
Replacement windows and doors of similar appearance
No permission needed (permitted development), unless an Article 4 direction removes it — check with the council
Part 1 Class A, A.3(a)
Listed buildings: 341 in the area (grade I: 12, II*: 14). 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: 29% 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 = 771)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
391
50.7%
Cavity wall, insulated (as built or unspecified)
142
18.4%
Cavity wall, filled
82
10.6%
Modern wall (U-value from the design)
54
7.0%
Cavity wall, unfilled
39
5.1%
Solid wall, insulated
24
3.1%
Timber frame
14
1.8%
Solid wall, internal insulation
12
1.6%
Cavity wall, partly insulated
10
1.3%
Solid wall, partly insulated
3
0.4%
Heating
Homes
Share
Gas boiler
635
82.4%
Electric (storage heaters, panels, boiler)
131
17.0%
Oil
2
0.3%
Solid fuel (wood, coal)
2
0.3%
Communal heating
1
0.1%
Loft / roof insulation
Homes
Share
No insulation
88
11.4%
Under 200 mm
192
24.9%
200 mm or more
234
30.4%
Insulated (depth not recorded)
110
14.3%
Flat or other home above
97
12.6%
Other
50
6.5%
Windows
Homes
Share
Double glazed
542
70.3%
Single glazed
153
19.8%
Secondary glazing
75
9.7%
Triple glazed
1
0.1%
CDE
Energy rating: B 29 (3.8%) · C 243 (31.5%) · D 317 (41.1%) · E 157 (20.4%) · F 19 (2.5%) · G 6 (0.8%). Houses and bungalows: 71% of the homes; solar panels on 0.3% of the certificates. Most common build period on the certificates: before 1900. Designated: 29 April 1970.
Compared with Dorset and England
Share of homes
Sherborne 1
All 311 areas in Dorset
England
Solid walls, no insulation
50.7%
37.3%
48.7%
Gas boiler
82.4%
60.1%
66.4%
Rated D–G
64.7%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 51% of these are from 2020 or later (latest 28 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 Dorset if in doubt.
Boundary: Dorset Council via planning.data.gov.uk (entity 44013875, reference SHER1, 55.4 ha). Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.