Solar panels, heat pumps and insulation in Clapham conservation area
In the Clapham 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 3% of it), but the published data does not say which rights it removes — check the direction before any work. The area has 83 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. 2,351 homes inside the boundary have an energy certificate: 50.8% are solid-wall homes with no wall insulation, 67.8% heat with a gas boiler and 39.1% are rated D–G; 50 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
2,351homes with an energy certificate
50.8%solid walls, no insulation
67.8%heated by a gas boiler
50heat pumps
Article 4: An Article 4 direction published by Lambeth covers part of this area (about 3% of it), but the published data does not say which rights it removes — check the direction before any work. (Modified Direction 3 - Town Centres)
What needs planning permission in Clapham
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: 83 in the area (grade I: 0, II*: 8). 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: 80% 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 = 2,351)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
1,195
50.8%
Modern wall (U-value from the design)
409
17.4%
Cavity wall, insulated (as built or unspecified)
353
15.0%
Timber frame
84
3.6%
Other or not known
73
3.1%
Solid wall, internal insulation
57
2.4%
Cavity wall, partly insulated
55
2.3%
Cavity wall, unfilled
45
1.9%
Solid wall, insulated
44
1.9%
Cavity wall, filled
26
1.1%
Solid wall, partly insulated
6
0.3%
Cavity wall, internal or external insulation
2
0.1%
Solid wall, external insulation
2
0.1%
Heating
Homes
Share
Gas boiler
1,595
67.8%
Communal heating
425
18.1%
Electric (storage heaters, panels, boiler)
277
11.8%
Heat pump
50
2.1%
LPG
3
0.1%
Solid fuel (wood, coal)
1
0.0%
Loft / roof insulation
Homes
Share
No insulation
292
12.4%
Under 200 mm
196
8.3%
200 mm or more
80
3.4%
Insulated (depth not recorded)
331
14.1%
Flat or other home above
1,259
53.6%
Other
193
8.2%
Windows
Homes
Share
Double glazed
1,878
79.9%
Single glazed
380
16.2%
Secondary glazing
85
3.6%
Triple glazed
7
0.3%
BCDE
Energy rating: A 1 (0.0%) · B 290 (12.3%) · C 1,140 (48.5%) · D 689 (29.3%) · E 193 (8.2%) · F 27 (1.1%) · G 11 (0.5%). Houses and bungalows: 20% of the homes; solar panels on 0.2% of the certificates. Most common build period on the certificates: before 1900. Designated: 20 June 1968.
Compared with Lambeth and England
Share of homes
Clapham
All 65 areas in Lambeth
England
Solid walls, no insulation
50.8%
64.5%
48.7%
Gas boiler
67.8%
73.7%
66.4%
Rated D–G
39.1%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 58% 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 Lambeth if in doubt.
Boundary: London Borough of Lambeth via planning.data.gov.uk (entity 44008585, reference CA1, 83.1 ha). Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.