Solar panels, heat pumps and insulation in Stockwell Park conservation area
In the Stockwell Park conservation area (Lambeth), 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 Lambeth covers part of this area (about 13% of it), but the published data does not say which rights it removes — check the direction before any work. The area has 63 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. 944 homes inside the boundary have an energy certificate: 43.6% are solid-wall homes with no wall insulation, 60.1% heat with a gas boiler and 36.7% 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
944homes with an energy certificate
43.6%solid walls, no insulation
60.1%heated by a gas boiler
0heat pumps
Article 4: An Article 4 direction published by Lambeth covers part of this area (about 13% of it), but the published data does not say which rights it removes — check the direction before any work. (STOCKWELL PARK)
What needs planning permission in Stockwell Park
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: 63 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: 81% 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 = 944)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
412
43.6%
Modern wall (U-value from the design)
216
22.9%
Cavity wall, insulated (as built or unspecified)
129
13.7%
Other or not known
115
12.2%
Timber frame
23
2.4%
Solid wall, insulated
21
2.2%
Solid wall, internal insulation
11
1.2%
Cavity wall, unfilled
8
0.8%
Solid wall, partly insulated
4
0.4%
Cavity wall, partly insulated
3
0.3%
Cavity wall, filled
2
0.2%
Heating
Homes
Share
Gas boiler
567
60.1%
Communal heating
346
36.7%
Electric (storage heaters, panels, boiler)
31
3.3%
Loft / roof insulation
Homes
Share
No insulation
102
10.8%
Under 200 mm
78
8.3%
200 mm or more
35
3.7%
Insulated (depth not recorded)
112
11.9%
Flat or other home above
538
57.0%
Other
79
8.4%
Windows
Homes
Share
Double glazed
638
67.6%
Single glazed
255
27.0%
Triple glazed
36
3.8%
Secondary glazing
15
1.6%
BCDE
Energy rating: B 260 (27.5%) · C 338 (35.8%) · D 246 (26.1%) · E 84 (8.9%) · F 12 (1.3%) · G 4 (0.4%). Houses and bungalows: 19% of the homes; solar panels on 0.0% of the certificates. Most common build period on the certificates: before 1900. Designated: 20 June 1968.
Compared with Lambeth and England
Share of homes
Stockwell Park
All 65 areas in Lambeth
England
Solid walls, no insulation
43.6%
64.5%
48.7%
Gas boiler
60.1%
73.7%
66.4%
Rated D–G
36.7%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 53% of these are from 2020 or later (latest 26 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 Lambeth if in doubt.
Boundary: London Borough of Lambeth via planning.data.gov.uk (entity 44000897, reference CA5, 20.5 ha). Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.