Solar panels, heat pumps and insulation in Brompton Lines conservation area
In the Brompton Lines conservation area (Medway), 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 Medway covers this area, but the published data does not say which rights it removes — check the direction before any work. The area has 66 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. 1,636 homes inside the boundary have an energy certificate: 20.1% are solid-wall homes with no wall insulation, 64.7% heat with a gas boiler and 35.0% are rated D–G; 15 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
1,636homes with an energy certificate
20.1%solid walls, no insulation
64.7%heated by a gas boiler
15heat pumps
Article 4: An Article 4 direction published by Medway covers this area, but the published data does not say which rights it removes — check the direction before any work. (Brompton Lines(1); Brompton Lines(2); Chatham Central & Brompton; Gillingham North; Gillingham South)
What needs planning permission in Brompton Lines
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: 66 in the area (grade I: 1, II*: 7). 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: 49% 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 = 1,636)
Walls
Homes
Share
Modern wall (U-value from the design)
418
25.6%
Cavity wall, filled
383
23.4%
Solid wall (brick or stone), no insulation
329
20.1%
Cavity wall, insulated (as built or unspecified)
191
11.7%
Cavity wall, unfilled
130
7.9%
Cavity wall, partly insulated
59
3.6%
Other or not known
45
2.8%
Timber frame
35
2.1%
Solid wall, internal insulation
24
1.5%
Solid wall, insulated
16
1.0%
Cavity wall, internal or external insulation
5
0.3%
Solid wall, external insulation
1
0.1%
Heating
Homes
Share
Gas boiler
1,058
64.7%
Electric (storage heaters, panels, boiler)
476
29.1%
Communal heating
87
5.3%
Heat pump
15
0.9%
Loft / roof insulation
Homes
Share
No insulation
115
7.0%
Under 200 mm
245
15.0%
200 mm or more
395
24.1%
Insulated (depth not recorded)
112
6.8%
Flat or other home above
558
34.1%
Other
211
12.9%
Windows
Homes
Share
Double glazed
1,588
97.1%
Single glazed
36
2.2%
Secondary glazing
9
0.6%
Triple glazed
3
0.2%
BCD
Energy rating: A 2 (0.1%) · B 415 (25.4%) · C 646 (39.5%) · D 468 (28.6%) · E 96 (5.9%) · F 8 (0.5%) · G 1 (0.1%). Houses and bungalows: 51% of the homes; solar panels on 0.1% of the certificates. Most common build period on the certificates: 1950-1966. Designated: 3 February 1981.
Compared with Medway and England
Share of homes
Brompton Lines
All 24 areas in Medway
England
Solid walls, no insulation
20.1%
35.9%
48.7%
Gas boiler
64.7%
69.7%
66.4%
Rated D–G
35.0%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 69% 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 Medway if in doubt.
Boundary: Medway Council via planning.data.gov.uk (entity 44009805, reference 7, 173.4 ha). Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.