Solar panels, heat pumps and insulation in St John's Grove conservation area
In the St John's Grove conservation area (Islington), 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 2 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. 1,011 homes inside the boundary have an energy certificate: 79.6% are solid-wall homes with no wall insulation, 90.9% heat with a gas boiler and 40.3% are rated D–G; 2 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
1,011homes with an energy certificate
79.6%solid walls, no insulation
90.9%heated by a gas boiler
2heat pumps
Article 4: Islington does not publish Article 4 areas on planning.data.gov.uk — check with the council.
What needs planning permission in St John's Grove
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: 2 in the area (grade I: 0, 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: 89% 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 = 1,011)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
805
79.6%
Cavity wall, unfilled
39
3.9%
Timber frame
28
2.8%
Modern wall (U-value from the design)
26
2.6%
Cavity wall, filled
24
2.4%
Cavity wall, insulated (as built or unspecified)
24
2.4%
Solid wall, internal insulation
21
2.1%
Cavity wall, partly insulated
17
1.7%
Solid wall, insulated
9
0.9%
Other or not known
6
0.6%
Solid wall, external insulation
6
0.6%
Solid wall, partly insulated
6
0.6%
Heating
Homes
Share
Gas boiler
919
90.9%
Electric (storage heaters, panels, boiler)
69
6.8%
Communal heating
19
1.9%
Heat pump
2
0.2%
LPG
2
0.2%
Loft / roof insulation
Homes
Share
No insulation
125
12.4%
Under 200 mm
110
10.9%
200 mm or more
69
6.8%
Insulated (depth not recorded)
86
8.5%
Flat or other home above
600
59.4%
Other
20
2.0%
Windows
Homes
Share
Double glazed
668
66.1%
Single glazed
313
31.0%
Secondary glazing
22
2.2%
Triple glazed
8
0.8%
CD
Energy rating: A 2 (0.2%) · B 28 (2.8%) · C 574 (56.8%) · D 329 (32.5%) · E 65 (6.4%) · F 10 (1.0%) · G 3 (0.3%). Houses and bungalows: 11% of the homes; solar panels on 0.1% of the certificates. Most common build period on the certificates: 1900-1929.
Compared with Islington and England
Share of homes
St John's Grove
All 41 areas in Islington
England
Solid walls, no insulation
79.6%
67.1%
48.7%
Gas boiler
90.9%
79.1%
66.4%
Rated D–G
40.3%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 68% of these are from 2020 or later (latest 28 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 Islington if in doubt.
Boundary: London Borough of Islington via planning.data.gov.uk (entity 44008989, reference 181_ISL_CA28, 19.6 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.