Solar panels, heat pumps and insulation in Streatham Park & Garrads Road conservation area
In the Streatham Park & Garrads Road 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. The area has 1 listed building; on a listed building solar panels and heat pumps are not permitted development at all and need planning permission and listed building consent. 622 homes inside the boundary have an energy certificate: 65.0% are solid-wall homes with no wall insulation, 85.2% heat with a gas boiler and 54.5% are rated D–G; 1 has 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
622homes with an energy certificate
65.0%solid walls, no insulation
85.2%heated by a gas boiler
1heat pumps
Article 4: Lambeth publishes its Article 4 areas on planning.data.gov.uk and none overlaps this area; a direction can still exist on paper, so check with the council.
What needs planning permission in Streatham Park & Garrads 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)
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)
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)
Replacement windows and doors of similar appearance
No permission needed (permitted development)
Part 1 Class A, A.3(a)
Listed buildings: 1 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 = 622)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
404
65.0%
Cavity wall, insulated (as built or unspecified)
47
7.6%
Timber frame
42
6.8%
Modern wall (U-value from the design)
40
6.4%
Cavity wall, partly insulated
37
5.9%
Cavity wall, unfilled
20
3.2%
Solid wall, internal insulation
11
1.8%
Other or not known
8
1.3%
Solid wall, insulated
6
1.0%
Cavity wall, filled
4
0.6%
Cavity wall, internal or external insulation
1
0.2%
Solid wall, external insulation
1
0.2%
Solid wall, partly insulated
1
0.2%
Heating
Homes
Share
Gas boiler
530
85.2%
Electric (storage heaters, panels, boiler)
65
10.5%
Communal heating
24
3.9%
LPG
2
0.3%
Heat pump
1
0.2%
Loft / roof insulation
Homes
Share
No insulation
85
13.7%
Under 200 mm
62
10.0%
200 mm or more
29
4.7%
Insulated (depth not recorded)
80
12.9%
Flat or other home above
332
53.5%
Other
33
5.3%
Windows
Homes
Share
Double glazed
482
77.5%
Single glazed
128
20.6%
Secondary glazing
10
1.6%
Triple glazed
2
0.3%
CDE
Energy rating: B 25 (4.0%) · C 258 (41.5%) · D 225 (36.2%) · E 91 (14.6%) · F 20 (3.2%) · G 3 (0.5%). Houses and bungalows: 19% of the homes; solar panels on 0.3% of the certificates. Most common build period on the certificates: 1900-1929. Designated: 31 March 1969.
Compared with Lambeth and England
Share of homes
Streatham Park & Garrads Road
All 65 areas in Lambeth
England
Solid walls, no insulation
65.0%
64.5%
48.7%
Gas boiler
85.2%
73.7%
66.4%
Rated D–G
54.5%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 57% 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 44000880, reference CA12, 18.5 ha). Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.