Solar panels, heat pumps and insulation in Oakhill (a) conservation area
In the Oakhill (a) conservation area (Kingston 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. An Article 4 direction published by Kingston upon Thames covers part of this area (about 10% of it) but deals with other things (such as changes of use); it does not change the rules below. The area has 9 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. 517 homes inside the boundary have an energy certificate: 48.2% are solid-wall homes with no wall insulation, 79.1% heat with a gas boiler and 50.5% 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
517homes with an energy certificate
48.2%solid walls, no insulation
79.1%heated by a gas boiler
1heat pumps
Article 4: An Article 4 direction published by Kingston upon Thames covers part of this area (about 10% of it) but deals with other things (such as changes of use); it does not change the rules below. (Ewell Road North)
What needs planning permission in Oakhill (a)
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: 9 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: 95% 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 = 517)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
249
48.2%
Modern wall (U-value from the design)
89
17.2%
Cavity wall, filled
50
9.7%
Cavity wall, unfilled
41
7.9%
Cavity wall, insulated (as built or unspecified)
36
7.0%
Solid wall, insulated
17
3.3%
Solid wall, internal insulation
13
2.5%
Timber frame
12
2.3%
Cavity wall, partly insulated
4
0.8%
Solid wall, partly insulated
3
0.6%
Other or not known
2
0.4%
Cavity wall, internal or external insulation
1
0.2%
Heating
Homes
Share
Gas boiler
409
79.1%
Electric (storage heaters, panels, boiler)
102
19.7%
Communal heating
5
1.0%
Heat pump
1
0.2%
Loft / roof insulation
Homes
Share
No insulation
58
11.2%
Under 200 mm
55
10.6%
200 mm or more
31
6.0%
Insulated (depth not recorded)
25
4.8%
Flat or other home above
299
57.8%
Other
49
9.5%
Windows
Homes
Share
Double glazed
441
85.3%
Single glazed
61
11.8%
Secondary glazing
15
2.9%
BCDE
Energy rating: B 62 (12.0%) · C 194 (37.5%) · D 195 (37.7%) · E 56 (10.8%) · F 8 (1.5%) · G 2 (0.4%). Houses and bungalows: 5% of the homes; solar panels on 0.0% of the certificates. Most common build period on the certificates: 1900-1929.
Compared with Kingston upon Thames and England
Share of homes
Oakhill (a)
All 28 areas in Kingston upon Thames
England
Solid walls, no insulation
48.2%
57.0%
48.7%
Gas boiler
79.1%
81.2%
66.4%
Rated D–G
50.5%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 56% of these are from 2020 or later (latest 29 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 Kingston upon Thames if in doubt.
Boundary: Royal Borough of Kingston upon Thames via planning.data.gov.uk (entity 44016354, reference 12, 15.5 ha). Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.