Solar panels, heat pumps and insulation in Stratford Place conservation area
In the Stratford Place conservation area (Westminster), 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 Westminster covers this area and removes permitted development rights for replacement windows and doors, and other alterations to the house, so there these need planning permission too. The area has 11 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. 187 homes inside the boundary have an energy certificate: 42.2% are solid-wall homes with no wall insulation, 35.8% heat with a gas boiler and 33.7% are rated D–G; 43 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
187homes with an energy certificate
42.2%solid walls, no insulation
35.8%heated by a gas boiler
43heat pumps
Article 4: An Article 4 direction published by Westminster covers this area and removes permitted development rights for replacement windows and doors, and other alterations to the house, so there these need planning permission too. (Article 4 Basement Development Permitted Rights Removed; Article 4 Direction Class E To C3 In Central Activities Zone)
What needs planning permission in Stratford Place
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
Planning permission needed (an Article 4 direction here removes this right)
Part 1 Class A, A.3(a)
Listed buildings: 11 in the area (grade I: 1, II*: 1). 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: 99% 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 = 187)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
79
42.2%
Modern wall (U-value from the design)
31
16.6%
Cavity wall, insulated (as built or unspecified)
16
8.6%
Solid wall, internal insulation
16
8.6%
Other or not known
14
7.5%
Solid wall, insulated
11
5.9%
Cavity wall, unfilled
10
5.3%
Timber frame
8
4.3%
Cavity wall, partly insulated
1
0.5%
Solid wall, partly insulated
1
0.5%
Heating
Homes
Share
Gas boiler
67
35.8%
Electric (storage heaters, panels, boiler)
49
26.2%
Heat pump
43
23.0%
Communal heating
27
14.4%
LPG
1
0.5%
Loft / roof insulation
Homes
Share
No insulation
13
7.0%
Under 200 mm
4
2.1%
200 mm or more
3
1.6%
Insulated (depth not recorded)
22
11.8%
Flat or other home above
136
72.7%
Other
9
4.8%
Windows
Homes
Share
Double glazed
138
73.8%
Secondary glazing
33
17.6%
Single glazed
16
8.6%
BCD
Energy rating: B 38 (20.3%) · C 86 (46.0%) · D 48 (25.7%) · E 12 (6.4%) · F 1 (0.5%) · G 2 (1.1%). Houses and bungalows: 1% of the homes; solar panels on 0.0% of the certificates. Most common build period on the certificates: before 1900. Designated: 20 November 1990.
Compared with Westminster and England
Share of homes
Stratford Place
All 56 areas in Westminster
England
Solid walls, no insulation
42.2%
66.4%
48.7%
Gas boiler
35.8%
59.2%
66.4%
Rated D–G
33.7%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 42% of these are from 2020 or later (latest 19 May 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 Westminster if in doubt.
Boundary: City of Westminster via planning.data.gov.uk (entity 44002866, reference CONARA/1250, 3.8 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.