About the Osterley Park Conservation Area
The Osterley Park Conservation Area covers about 285 hectares and was designated by London Borough of Hounslow in 1988. Inside the boundary are 15 listed buildings (4 Grade I, 1 Grade II*, 10 Grade II). The most significant is Aviary Or Little Orangerey in Osterley Park, Grade I. Part of the area lies in flood zone 3, so an extension may need a flood risk assessment.
What changes inside the conservation area
Conservation areas are “Article 2(3) land”. You keep most permitted development rights, but these are removed or tightened.
- Rear extensionElsewhere: 3 m · 6 m with PANo 6 m / 8 m prior approval
- Two-storey extensionElsewhere: 3 mNeeds planning permission
- Side extensionElsewhere: Half the widthNeeds planning permission
- Loft conversionElsewhere: 50 m³Needs planning permission
- Garden roomElsewhere: 2.5 m high by boundariesNot beside the house
- PorchElsewhere: 3 m²Same limits
- Solar panelsElsewhere: 0.2 m projectionSame limits
- Air source heat pumpElsewhere: 1 unitNot facing the road
- Fences, walls and gatesElsewhere: 2 m · 1 m by a roadSame limits
- External claddingElsewhere: Matching materialsNeeds planning permission
- Tree workElsewhere: No notice6 weeks’ notice to the council
- Demolition (over 115 m³)Elsewhere: AllowedNeeds planning permission
Limits for a semi-detached house under the GPDO 2015. An Article 4 direction can remove more.
Article 4 directions here
These overlap the conservation area. Householder directions remove more of the rights above; change-of-use ones don’t affect extending a house.
- Dwellinghouses (C3) to small HMOs (C4) - borough-wide Article 4 DirectionChange of use
- Change of use or development that would result in new dwellings (Class MA/ZA)Change of use
Listed buildings in the conservation area
Any work affecting these needs listed building consent, inside or out. Each links to its entry on the National Heritage List.
- Aviary Or Little Orangerey in Osterley ParkGrade I
- Osterley HouseGrade I
- Osterley House StablesGrade I
- The Temple in Osterley ParkGrade I
- Roman BridgeGrade II*
- 133, Jersey RoadGrade II
- 135, Jersey RoadGrade II
- Bridge Within Osterley ParkGrade II
- Entrance Lodges to Osterley ParkGrade II
- Garden Walls to North of Osterley Park FarmhouseGrade II
- Garden Walls to South of Osterley Park FarmhouseGrade II
- Gate Piers Within Osterley ParkGrade II
- Osterley Park FarmhouseGrade II
- Pavilion and ClubhouseGrade II
- Wyke Gardens, Wyke GreenGrade II
Streets in the conservation area
Streets with listed buildings inside the boundary. Boundaries often split a street — check your exact address.
The council’s appraisal
WEBOsterley Park Conservation Area AppraisalLondon Borough of Hounslow’s description of the area’s character — what planners look at when you apply.Open on council site ↗Nearby conservation areas
Boundary and listed buildings from London Borough of Hounslow and Historic England via planning.data.gov.uk (OGL). Guidance only — not an official council check.