Solar panels, heat pumps and insulation in Honiton conservation area
In the Honiton conservation area (East Devon), 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 86 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. 640 homes inside the boundary have an energy certificate: 40.6% are solid-wall homes with no wall insulation, 64.4% heat with a gas boiler and 53.6% are rated D–G; 3 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
640homes with an energy certificate
40.6%solid walls, no insulation
64.4%heated by a gas boiler
3heat pumps
Article 4: East Devon does not publish Article 4 areas on planning.data.gov.uk — check with the council.
What needs planning permission in Honiton
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: 86 in the area (grade I: 0, II*: 4). 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: 48% 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 = 640)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
260
40.6%
Cavity wall, insulated (as built or unspecified)
140
21.9%
Cavity wall, filled
66
10.3%
Modern wall (U-value from the design)
53
8.3%
Cavity wall, unfilled
36
5.6%
Timber frame
26
4.1%
Solid wall, insulated
24
3.8%
Cavity wall, partly insulated
18
2.8%
Solid wall, internal insulation
13
2.0%
Solid wall, external insulation
2
0.3%
Solid wall, partly insulated
2
0.3%
Heating
Homes
Share
Gas boiler
412
64.4%
Electric (storage heaters, panels, boiler)
213
33.3%
Communal heating
11
1.7%
Heat pump
3
0.5%
Solid fuel (wood, coal)
1
0.2%
Loft / roof insulation
Homes
Share
No insulation
63
9.8%
Under 200 mm
166
25.9%
200 mm or more
176
27.5%
Insulated (depth not recorded)
58
9.1%
Flat or other home above
130
20.3%
Other
47
7.3%
Windows
Homes
Share
Double glazed
562
87.8%
Single glazed
57
8.9%
Secondary glazing
19
3.0%
Triple glazed
2
0.3%
CDE
Energy rating: A 1 (0.2%) · B 38 (5.9%) · C 258 (40.3%) · D 226 (35.3%) · E 87 (13.6%) · F 24 (3.8%) · G 6 (0.9%). Houses and bungalows: 52% of the homes; solar panels on 0.3% of the certificates. Most common build period on the certificates: before 1900. Designated: 1 May 1972.
Compared with East Devon and England
Share of homes
Honiton
All 32 areas in East Devon
England
Solid walls, no insulation
40.6%
49.6%
48.7%
Gas boiler
64.4%
68.4%
66.4%
Rated D–G
53.6%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 55% 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 East Devon if in doubt.
Boundary: East Devon District Council via planning.data.gov.uk (entity 44012462, reference 9357, 21.1 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.