Solar panels, heat pumps and insulation in Walworth Road conservation area
In the Walworth Road conservation area (Southwark), 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 Southwark covers this area, but the published data does not say which rights it removes — check the direction before any work. The area has 6 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. 763 homes inside the boundary have an energy certificate: 54.3% are solid-wall homes with no wall insulation, 64.0% heat with a gas boiler and 38.3% 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
763homes with an energy certificate
54.3%solid walls, no insulation
64.0%heated by a gas boiler
3heat pumps
Article 4: An Article 4 direction published by Southwark covers this area, but the published data does not say which rights it removes — check the direction before any work. (Central Activities Zone; Elephant and Castle Major Town Centre; Liam Ogs; Protected shopping frontage SF23: Walworth Road, East Street and Camberwell Road; Protected shopping frontage SF2: Walworth Road; RED LION)
What needs planning permission in Walworth Road
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: 6 in the area. 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: 97% 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 = 763)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
414
54.3%
Modern wall (U-value from the design)
162
21.2%
Cavity wall, insulated (as built or unspecified)
68
8.9%
Timber frame
30
3.9%
Solid wall, internal insulation
26
3.4%
Cavity wall, unfilled
20
2.6%
Cavity wall, partly insulated
13
1.7%
Cavity wall, filled
12
1.6%
Solid wall, insulated
9
1.2%
Solid wall, partly insulated
4
0.5%
Other or not known
3
0.4%
Cavity wall, internal or external insulation
2
0.3%
Heating
Homes
Share
Gas boiler
488
64.0%
Electric (storage heaters, panels, boiler)
180
23.6%
Communal heating
92
12.1%
Heat pump
3
0.4%
Loft / roof insulation
Homes
Share
No insulation
129
16.9%
Under 200 mm
31
4.1%
200 mm or more
27
3.5%
Insulated (depth not recorded)
64
8.4%
Flat or other home above
421
55.2%
Other
91
11.9%
Windows
Homes
Share
Double glazed
709
92.9%
Single glazed
46
6.0%
Secondary glazing
8
1.0%
BCDE
Energy rating: A 2 (0.3%) · B 140 (18.3%) · C 329 (43.1%) · D 203 (26.6%) · E 72 (9.4%) · F 12 (1.6%) · G 5 (0.7%). Houses and bungalows: 3% of the homes; solar panels on 0.0% of the certificates. Most common build period on the certificates: 1900-1929. Designated: 22 March 2016.
Compared with Southwark and England
Share of homes
Walworth Road
All 56 areas in Southwark
England
Solid walls, no insulation
54.3%
56.7%
48.7%
Gas boiler
64.0%
71.3%
66.4%
Rated D–G
38.3%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 56% of these are from 2020 or later (latest 30 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 Southwark if in doubt.
Boundary: London Borough of Southwark via planning.data.gov.uk (entity 44010264, reference 48, 12.4 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.