Solar panels, heat pumps and insulation in Wymondham (12/00046/CONARA) conservation area
In the Wymondham conservation area (South Norfolk), 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 South Norfolk covers part of this area (about 4% of it), but the published data does not say which rights it removes — check the direction before any work. The area has 136 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. 496 homes inside the boundary have an energy certificate: 51.0% are solid-wall homes with no wall insulation, 76.6% heat with a gas boiler and 60.7% are rated D–G; 2 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
496homes with an energy certificate
51.0%solid walls, no insulation
76.6%heated by a gas boiler
2heat pumps
Article 4: An Article 4 direction published by South Norfolk covers part of this area (about 4% of it), but the published data does not say which rights it removes — check the direction before any work. (9-23 (odds) and 10 Church Street; Becketswell Road; Friarscroft Terrace, 25-35 Friarscroft Lane)
What needs planning permission in Wymondham
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: 136 in the area (grade I: 3, 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: 34% 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 = 496)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
253
51.0%
Cavity wall, insulated (as built or unspecified)
93
18.8%
Cavity wall, filled
57
11.5%
Modern wall (U-value from the design)
28
5.6%
Timber frame
20
4.0%
Cavity wall, unfilled
14
2.8%
Solid wall, internal insulation
13
2.6%
Solid wall, insulated
8
1.6%
Cavity wall, partly insulated
7
1.4%
Other or not known
2
0.4%
Solid wall, partly insulated
1
0.2%
Heating
Homes
Share
Gas boiler
380
76.6%
Electric (storage heaters, panels, boiler)
103
20.8%
Communal heating
6
1.2%
Solid fuel (wood, coal)
3
0.6%
Heat pump
2
0.4%
Oil
2
0.4%
Loft / roof insulation
Homes
Share
No insulation
51
10.3%
Under 200 mm
146
29.4%
200 mm or more
149
30.0%
Insulated (depth not recorded)
57
11.5%
Flat or other home above
65
13.1%
Other
28
5.6%
Windows
Homes
Share
Double glazed
407
82.1%
Single glazed
64
12.9%
Secondary glazing
24
4.8%
Triple glazed
1
0.2%
CDE
Energy rating: A 2 (0.4%) · B 30 (6.0%) · C 163 (32.9%) · D 197 (39.7%) · E 87 (17.5%) · F 14 (2.8%) · G 3 (0.6%). Houses and bungalows: 66% of the homes; solar panels on 0.2% of the certificates. Most common build period on the certificates: before 1900. Designated: 1 January 1974.
Compared with South Norfolk and England
Share of homes
Wymondham
All 84 areas in South Norfolk
England
Solid walls, no insulation
51.0%
41.0%
48.7%
Gas boiler
76.6%
47.8%
66.4%
Rated D–G
60.7%
—
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 South Norfolk if in doubt.
Boundary: South Norfolk District Council via planning.data.gov.uk (entity 44013418, reference 12/00046/CONARA, 34.0 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.