About the Coppermill Lock Conservation Area
The Coppermill Lock Conservation Area covers about 9.9 hectares within London Borough of Hillingdon’s area. Inside the boundary are 3 listed buildings, all Grade II. 4 Article 4 directions over the area remove further householder rights, on top of the conservation area limits below. 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.
- Changes of use from commercial, business and service uses to dwellinghousesChange of use
- Residential extensionsHouseholder works
- Construction of new dwellinghouses in employment areasHouseholder works
- Construction of new dwellinghouses in employment areasHouseholder works
- Construction of new dwellinghouses in employment areasHouseholder works
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.
- Premises of Harefield Rubber Company Central BuildingGrade II
- The Red Cottage the Red HouseGrade II
- West Factory Block on Premises of Harefield Rubber CompanyGrade II
Nearby conservation areas
Boundary and listed buildings from London Borough of Hillingdon and Historic England via planning.data.gov.uk (OGL). Guidance only — not an official council check.