Solar panels, heat pumps and insulation in Stony Stratford conservation area
In the Stony Stratford conservation area (Milton Keynes), 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 Milton Keynes covers this area, but the published data does not say which rights it removes — check the direction before any work. The area has 140 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. 359 homes inside the boundary have an energy certificate: 70.8% are solid-wall homes with no wall insulation, 82.5% heat with a gas boiler and 79.4% 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
359homes with an energy certificate
70.8%solid walls, no insulation
82.5%heated by a gas boiler
1heat pumps
Article 4: An Article 4 direction published by Milton Keynes covers this area, but the published data does not say which rights it removes — check the direction before any work. (Article 4 Direction relating to Houses in Multiple Occupation (HIMO) - Immediate direction; Article 4 Direction relating to Houses in Multiple Occupation (HIMO) - Non immediate direction)
What needs planning permission in Stony Stratford
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: 140 in the area (grade I: 0, II*: 9). 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: 23% 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 = 359)
Walls
Homes
Share
Solid wall (brick or stone), no insulation
254
70.8%
Modern wall (U-value from the design)
29
8.1%
Cavity wall, insulated (as built or unspecified)
22
6.1%
Solid wall, insulated
14
3.9%
Solid wall, internal insulation
10
2.8%
Cavity wall, partly insulated
8
2.2%
Cavity wall, unfilled
7
1.9%
Cavity wall, filled
6
1.7%
Timber frame
5
1.4%
Other or not known
3
0.8%
Solid wall, external insulation
1
0.3%
Heating
Homes
Share
Gas boiler
296
82.5%
Electric (storage heaters, panels, boiler)
52
14.5%
Communal heating
7
1.9%
Oil
3
0.8%
Heat pump
1
0.3%
Loft / roof insulation
Homes
Share
No insulation
85
23.7%
Under 200 mm
111
31.0%
200 mm or more
63
17.6%
Insulated (depth not recorded)
49
13.7%
Flat or other home above
23
6.4%
Other
27
7.5%
Windows
Homes
Share
Double glazed
263
73.3%
Single glazed
68
18.9%
Secondary glazing
27
7.5%
Triple glazed
1
0.3%
CDE
Energy rating: B 14 (3.9%) · C 60 (16.7%) · D 147 (40.9%) · E 115 (32.0%) · F 17 (4.7%) · G 6 (1.7%). Houses and bungalows: 77% of the homes; solar panels on 0.3% of the certificates. Most common build period on the certificates: before 1900. Designated: 24 March 2020.
Compared with Milton Keynes and England
Share of homes
Stony Stratford
All 27 areas in Milton Keynes
England
Solid walls, no insulation
70.8%
62.6%
48.7%
Gas boiler
82.5%
79.6%
66.4%
Rated D–G
79.4%
—
56.5%
Caveats
Certificates describe a home when it was assessed; 54% of these are from 2020 or later (latest 10 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 Milton Keynes if in doubt.
Boundary: Milton Keynes City Council via planning.data.gov.uk (entity 44014138, reference CA16, 27.2 ha); the council's appraisal or map. Homes are placed by the coordinates of their UPRN (OS Open UPRN); addresses are not shown.