Solar panels, heat pumps and insulation in Kew Gardens conservation area
In the Kew Gardens conservation area (Richmond upon Thames), 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 3 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. 786 homes inside the boundary have an energy certificate: 58.5% are solid-wall homes with no wall insulation, 85.2% heat with a gas boiler and 67.4% are rated D–G; 3 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
786homes with an energy certificate
58.5%solid walls, no insulation
85.2%heated by a gas boiler
3heat pumps
Article 4: Richmond upon Thames does not publish Article 4 areas on planning.data.gov.uk — check with the council.
What needs planning permission in Kew Gardens
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: 3 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: 63% 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 = 786)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
460
58.5%
Cavity wall, unfilled
121
15.4%
Cavity wall, insulated (as built or unspecified)
70
8.9%
Timber frame
37
4.7%
Cavity wall, filled
26
3.3%
Modern wall (U-value from the design)
23
2.9%
Solid wall, internal insulation
18
2.3%
Cavity wall, partly insulated
14
1.8%
Other or not known
9
1.1%
Solid wall, insulated
6
0.8%
Cavity wall, internal or external insulation
1
0.1%
Solid wall, partly insulated
1
0.1%
Heating
Homes
Share
Gas boiler
670
85.2%
Electric (storage heaters, panels, boiler)
100
12.7%
Communal heating
11
1.4%
Heat pump
3
0.4%
LPG
2
0.3%
Loft / roof insulation
Homes
Share
No insulation
156
19.8%
Under 200 mm
114
14.5%
200 mm or more
42
5.3%
Insulated (depth not recorded)
169
21.5%
Flat or other home above
284
36.1%
Other
21
2.7%
Windows
Homes
Share
Double glazed
633
80.5%
Single glazed
110
14.0%
Secondary glazing
41
5.2%
Triple glazed
2
0.3%
CDE
Energy rating: B 15 (1.9%) · C 241 (30.7%) · D 301 (38.3%) · E 186 (23.7%) · F 39 (5.0%) · G 4 (0.5%). Houses and bungalows: 37% of the homes; solar panels on 0.1% of the certificates. Most common build period on the certificates: 1900-1929. Designated: 27 April 2004.
Compared with Richmond upon Thames and England
Share of homes
Kew Gardens
All 85 areas in Richmond upon Thames
England
Solid walls, no insulation
58.5%
63.5%
48.7%
Gas boiler
85.2%
83.6%
66.4%
Rated D–G
67.4%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 50% of these are from 2020 or later (latest 25 September 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 Richmond upon Thames if in doubt.
Boundary: London Borough of Richmond upon Thames via planning.data.gov.uk (entity 44009083, reference 7360, 31.9 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.