Solar panels, heat pumps and insulation in Topsham conservation area
In the Topsham conservation area (Exeter), 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 Exeter covers part of this area (about 1% of it), but the published data does not say which rights it removes — check the direction before any work. The area has 217 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. 916 homes inside the boundary have an energy certificate: 38.6% are solid-wall homes with no wall insulation, 83.6% heat with a gas boiler and 63.4% are rated D–G; 11 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
916homes with an energy certificate
38.6%solid walls, no insulation
83.6%heated by a gas boiler
11heat pumps
Article 4: An Article 4 direction published by Exeter covers part of this area (about 1% of it), but the published data does not say which rights it removes — check the direction before any work. (Land at the Strand, Topsham)
What needs planning permission in Topsham
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: 217 in the area (grade I: 0, II*: 16). 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: 35% 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 = 916)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
354
38.6%
Cavity wall, unfilled
195
21.3%
Cavity wall, filled
130
14.2%
Cavity wall, insulated (as built or unspecified)
123
13.4%
Modern wall (U-value from the design)
35
3.8%
Timber frame
31
3.4%
Cavity wall, partly insulated
19
2.1%
Solid wall, insulated
12
1.3%
Solid wall, internal insulation
7
0.8%
Solid wall, partly insulated
6
0.7%
Cavity wall, internal or external insulation
2
0.2%
Other or not known
2
0.2%
Heating
Homes
Share
Gas boiler
766
83.6%
Electric (storage heaters, panels, boiler)
121
13.2%
Heat pump
11
1.2%
Communal heating
9
1.0%
Oil
6
0.7%
Solid fuel (wood, coal)
3
0.3%
Loft / roof insulation
Homes
Share
No insulation
126
13.8%
Under 200 mm
254
27.7%
200 mm or more
222
24.2%
Insulated (depth not recorded)
129
14.1%
Flat or other home above
149
16.3%
Other
36
3.9%
Windows
Homes
Share
Double glazed
749
81.8%
Single glazed
103
11.2%
Secondary glazing
63
6.9%
Triple glazed
1
0.1%
CDE
Energy rating: A 9 (1.0%) · B 36 (3.9%) · C 290 (31.7%) · D 375 (40.9%) · E 178 (19.4%) · F 23 (2.5%) · G 5 (0.5%). Houses and bungalows: 65% of the homes; solar panels on 0.5% of the certificates. Most common build period on the certificates: before 1900. Designated: 14 December 1967.
Compared with Exeter and England
Share of homes
Topsham
All 20 areas in Exeter
England
Solid walls, no insulation
38.6%
35.2%
48.7%
Gas boiler
83.6%
69.4%
66.4%
Rated D–G
63.4%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 55% of these are from 2020 or later (latest 20 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 Exeter if in doubt.
Boundary: Exeter City Council via planning.data.gov.uk (entity 44015010, reference CA20, 72.3 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.