Solar panels, heat pumps and insulation in Thatcham conservation area
In the Thatcham conservation area (West Berkshire), 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 23 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. 114 homes inside the boundary have an energy certificate: 20.2% are solid-wall homes with no wall insulation, 45.6% heat with a gas boiler and 51.8% 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
114homes with an energy certificate
20.2%solid walls, no insulation
45.6%heated by a gas boiler
3heat pumps
Article 4: West Berkshire publishes its Article 4 areas on planning.data.gov.uk and none overlaps this area; a direction can still exist on paper, so check with the council.
What needs planning permission in Thatcham
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: 23 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: 80% 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 = 114)
Walls
Homes
Share
Modern wall (U-value from the design)
27
23.7%
Cavity wall, insulated (as built or unspecified)
24
21.1%
Solid wall (brick or stone), no insulation
23
20.2%
Timber frame
14
12.3%
Cavity wall, unfilled
13
11.4%
Cavity wall, filled
6
5.3%
Solid wall, internal insulation
4
3.5%
Cavity wall, partly insulated
2
1.8%
Other or not known
1
0.9%
Heating
Homes
Share
Gas boiler
52
45.6%
Electric (storage heaters, panels, boiler)
47
41.2%
Communal heating
11
9.6%
Heat pump
3
2.6%
Solid fuel (wood, coal)
1
0.9%
Loft / roof insulation
Homes
Share
No insulation
7
6.1%
Under 200 mm
19
16.7%
200 mm or more
25
21.9%
Insulated (depth not recorded)
17
14.9%
Flat or other home above
21
18.4%
Other
25
21.9%
Windows
Homes
Share
Double glazed
107
93.9%
Secondary glazing
4
3.5%
Single glazed
3
2.6%
BCDE
Energy rating: B 14 (12.3%) · C 41 (36.0%) · D 28 (24.6%) · E 25 (21.9%) · F 3 (2.6%) · G 3 (2.6%). Houses and bungalows: 20% of the homes; solar panels on 0.0% of the certificates. Most common build period on the certificates: before 1900. Designated: 13 June 1980.
Compared with West Berkshire and England
Share of homes
Thatcham
All 51 areas in West Berkshire
England
Solid walls, no insulation
20.2%
30.0%
48.7%
Gas boiler
45.6%
39.9%
66.4%
Rated D–G
51.8%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 53% of these are from 2020 or later (latest 21 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 West Berkshire if in doubt.
Boundary: West Berkshire Council via planning.data.gov.uk (entity 44010139, reference 23/00152/CONARA, 7.0 ha). Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.