Loft conversions in Greenwich depend on the house. Typical homes here: Georgian and early Victorian terraces and villas in West Greenwich, Blackheath and Greenwich town centre; Victorian terraces in Charlton, Plumstead, Westcombe Park and Woolwich. Designations to check first: Conservation areas; Article 4 directions; Thames flood risk. Applications are decided by Royal Borough of Greenwich and the Royal Greenwich Local Plan: Core Strategy with Detailed Policies (2014).
The permitted development rules for loft conversions
A loft conversion with a rear dormer is permitted development on a house if the added roof volume is no more than 40 m³ on a terraced house or 50 m³ on a semi-detached or detached house, the dormer sits at least 200 mm back from the eaves and no higher than the ridge, there is no dormer on the roof slope facing the road, materials are similar in appearance, and side windows are obscure-glazed.
Flats and maisonettes have no permitted development rights, so a loft to a top-floor flat always needs planning permission. Full-width box dormers that reach the ridge, and hip-to-gable conversions on semis whose volume exceeds 50 m³, also fall outside the allowance.
What changes in Greenwich
Roof extensions are not permitted development in a conservation area, so a dormer or hip-to-gable there needs a householder planning application designed to the area's appraisal.
The local constraints that most often decide the route in Greenwich are listed below, taken from our Greenwich area page. Each one is a reason to confirm the address on Greenwich's constraints map before relying on permitted development.
- Conservation areas. Royal Greenwich has numerous conservation areas, including West Greenwich, Blackheath, Blackheath Park, Westcombe Park, Charlton Village, Eltham Palace, the Progress Estate and Woolwich Common. Source
- Article 4 directions. Several conservation areas, notably the Progress Estate in Eltham and parts of Blackheath, have Article 4 directions removing permitted development for external alterations, so most changes need planning permission. Source
- Thames flood risk. The riverside from Greenwich Peninsula through Charlton, Woolwich and Thamesmead lies in Flood Zones 2 and 3 behind the Thames Barrier and river defences. Source
- Metropolitan Open Land and Royal Parks. Blackheath, Greenwich Park, Woolwich Common, Oxleas Wood and Shooters Hill are Metropolitan Open Land or Royal Park. Source
- Listed buildings. Greenwich town centre, Blackheath and Eltham contain a high concentration of listed buildings. Source
What Greenwich planning officers look for
Common refusal reasons are rear extensions that breach the 45-degree line or exceed the neighbour's depth, roof extensions in conservation areas that break the roofline of a terrace, front dormers, and alterations to Span houses or the Progress Estate that depart from the original detailing. The council offers a paid pre-application service, which we recommend in the World Heritage Site buffer zone and Blackheath. Decisions often run past 8 weeks; allow 10–14 weeks.
Fees and timelines
Greenwich decides a householder application or a Lawful Development Certificate within 8 weeks of validation. The council fee is £528 for a householder application and £264 for a Lawful Development Certificate (England, from 1 April 2025; verify before applying).
Our own fee is fixed once quoted. The quote tool gives an indicative figure in minutes and a written quote follows within 24 hours.
Primary sources
- The Town and Country Planning (General Permitted Development) (England) Order 2015, Schedule 2: the permitted development limits quoted above.
- Planning Portal: do you need permission: the national guidance and the application service every council accepts.
- Royal Borough of Greenwich: planning: the council's own constraints map, validation checklist and pre-application service.

