Solar panels, heat pumps and insulation in Sydenham Park conservation area
In the Sydenham Park conservation area (Lewisham), 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 Lewisham covers this area, but the published data does not say which rights it removes — check the direction before any work. 209 homes inside the boundary have an energy certificate: 55.0% are solid-wall homes with no wall insulation, 87.1% heat with a gas boiler and 58.9% 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
209homes with an energy certificate
55.0%solid walls, no insulation
87.1%heated by a gas boiler
0heat pumps
Article 4: An Article 4 direction published by Lewisham covers this area, but the published data does not say which rights it removes — check the direction before any work. (Small HMO Northern Extension; Sydenham Park Article 4 Direction)
What needs planning permission in Sydenham 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: none recorded inside the boundary; on a listed building, solar panels and heat pumps are not permitted development and need listed building consent.
Flats: 85% 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 = 209)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
115
55.0%
Cavity wall, filled
28
13.4%
Cavity wall, insulated (as built or unspecified)
23
11.0%
Cavity wall, unfilled
19
9.1%
Solid wall, insulated
10
4.8%
Modern wall (U-value from the design)
6
2.9%
Timber frame
3
1.4%
Cavity wall, partly insulated
2
1.0%
Solid wall, partly insulated
2
1.0%
Solid wall, internal insulation
1
0.5%
Heating
Homes
Share
Gas boiler
182
87.1%
Communal heating
20
9.6%
Electric (storage heaters, panels, boiler)
7
3.3%
Loft / roof insulation
Homes
Share
No insulation
21
10.0%
Under 200 mm
25
12.0%
200 mm or more
13
6.2%
Insulated (depth not recorded)
30
14.4%
Flat or other home above
115
55.0%
Other
5
2.4%
Windows
Homes
Share
Double glazed
127
60.8%
Single glazed
80
38.3%
Secondary glazing
2
1.0%
CD
Energy rating: B 1 (0.5%) · C 85 (40.7%) · D 104 (49.8%) · E 14 (6.7%) · F 4 (1.9%) · G 1 (0.5%). Houses and bungalows: 15% of the homes; solar panels on 0.0% of the certificates. Most common build period on the certificates: before 1900. Designated: 1 January 1973.
Compared with Lewisham and England
Share of homes
Sydenham Park
All 31 areas in Lewisham
England
Solid walls, no insulation
55.0%
69.0%
48.7%
Gas boiler
87.1%
85.5%
66.4%
Rated D–G
58.9%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 40% of these are from 2020 or later (latest 8 July 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 Lewisham if in doubt.
Boundary: London Borough of Lewisham via planning.data.gov.uk (entity 44014970, reference LEWCA6, 5.4 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.