Lofts in Ealing sit on three different kinds of roof. The Edwardian semis and detached houses of Ealing, Northfields and Pitshanger have deep roof spaces and are the most likely to be near a conservation area. The Victorian terraces of Acton, Hanwell and West Ealing share a roof line with their neighbours, so a rear dormer has to read as part of that run. On the 1930s semis of Greenford, Perivale and Northolt the question is usually the hipped end: whether to square it off into a gable, and what the house next door has done. We settle which of the three applies before any drawing starts.
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 Ealing
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 Ealing are listed below, taken from our Ealing area page. Each one is a reason to confirm the address on Ealing's constraints map before relying on permitted development.
- Conservation areas. Ealing has numerous conservation areas, including Brentham Garden Suburb, Bedford Park (shared with Hounslow), Ealing Common, Ealing Town Centre, Hanger Hill Garden Estate, Haven Green and Hanwell Village Green. Source
- Article 4 directions in garden suburbs and estates. Brentham Garden Suburb, Bedford Park and the Hanger Hill Garden Estate, among others, have Article 4 directions removing permitted development for external alterations, so most changes need planning permission. Source
- Flood risk: River Brent and Grand Union Canal. The River Brent through Hanwell, Perivale and Greenford, and the Grand Union Canal through Southall and Alperton borders, place some streets in Flood Zones 2 and 3. Source
- Green Belt and Metropolitan Open Land. Northolt, Horsenden Hill, Perivale Park and the Brent River Park include Green Belt and Metropolitan Open Land. Source
- HMO Article 4 direction. Ealing may operate an Article 4 direction requiring planning permission to convert a house into a small house in multiple occupation (HMO). Source
What Ealing's roof extension guidance expects of a loft
Ealing's Residential Extensions guidance (SPD 4) is listed on the council's website as interim guidance, kept pending a replacement SPD after the old Unitary Development Plan was superseded in December 2013. The council says such documents do not carry the weight of the development plan but are a material consideration in deciding applications. It is an old document, so we treat it as a guide to what officers look for, not as current policy.
For dormers it asks that they do not look obtrusive or take up the whole of a roof slope, that rear dormers are preferred to side dormers, and that front dormers are rarely acceptable. A dormer should sit at least 0.5 m down from the ridge, 0.5 m in from the edges of the roof and 0.5 m above the eaves, and should not wrap around two roof slopes or rise above the ridge. It also says that mansard roofs which change the slope of the roof will not usually be acceptable, and that rooflights are a lower-impact alternative to a dormer.
On hipped roofs it is blunt: where a semi-detached or terraced house wants to change a hip to a gable and planning permission is needed, permission will normally be refused because it unbalances the pair or terrace. The council's later Housing Design Guidance (November 2022) says something similar in softer words: for a loft on a semi, take account of the neighbouring house and roof line and avoid changing a hip to a gable if the house next door keeps its hip. It also advises avoiding front windows for loft conversions, says rear dormers can provide extra space, and calls its advice principles rather than prescriptive rules.
Conservation areas and Article 4 directions on roofs in Ealing
Ealing's conservation area FAQs list the works that need planning permission in a conservation area for a single dwelling, including raising the ridge or expanding the size of a roof and installing a dormer window. They add that permitted development rights do not apply to flats or houses converted to flats, and that the council encourages a pre-application request before a full application.
Some conservation areas go further. The council's Article 4 page lists directions covering roof works in Bedford Park, in Churchfields (Half Acre Road) and in Ealing Town Centre (The Grove), each of which names the enlargement of a dwelling through an addition or alteration to its roof. In the Hanger Hill Haymills Estate the direction covers alterations to roof slopes, including rooflights. Brentham Garden Estate and the Hanger Hill Garden Estate are covered by directions on the alteration of a dwelling house, including replacement of roof materials. Directions vary from area to area, so check the one for your street before assuming a roof light or tile change is free of control.
What Ealing planning officers look for
Common refusal reasons are two-storey side extensions without a set-back from the front wall, rear extensions that fail the 45-degree test, and roof extensions in conservation areas that do not match the existing pattern. On the 1930s semis of Greenford and Perivale, hip-to-gable lofts and 4–6 m rear extensions are often possible under permitted development, but where planning permission is needed the council's guidance says a hip-to-gable on a semi will normally be refused. The council offers a paid pre-application service, which we recommend for Brentham, Bedford Park and Hanger Hill. Decisions often run past 8 weeks; allow 10–14 weeks.
Fees and timelines
Ealing 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
- Ealing Council: SPD 4 Residential extensions (interim guidance)
- Ealing Council: Supplementary planning guidance and documents, interim guidance
- Ealing Council: Housing Design Guidance (November 2022)
- Ealing Council: Conservation areas FAQs
- Ealing Council: Article 4 Directions in conservation areas
- 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.
- London Borough of Ealing: planning: the council's own constraints map, validation checklist and pre-application service.
