A two-storey extension in Reigate and Banstead usually means one of three houses. On the 1930s semis of Nork, Banstead, Earlswood and Merstham it is a side extension over the garage or a rear extension with a bedroom above. On the Victorian and Edwardian terraces and villas of Reigate and Redhill it is a rear addition that has to answer to the neighbours on both sides. On the large detached houses of Reigate Hill, Kingswood and Chipstead it is a bigger addition on a wooded plot, mostly in the Green Belt. Which of these you own decides how the council's guidance reads.
The permitted development rules for two-storey extensions
A two-storey rear extension is permitted development only within tight limits: no more than 3 m deep, at least 7 m from the rear boundary, no higher than the existing house, eaves matching the existing eaves, materials similar in appearance, and any upper-floor side window obscure-glazed and non-opening below 1.7 m.
Most two-storey extensions exceed one of those limits, most often the 7 m rear boundary rule on London plots, so the usual route is a householder planning application. Flats have no permitted development rights.
What changes in Reigate and Banstead
Extensions of more than one storey are not permitted development in a conservation area, so planning permission is always needed there.
The local constraints that most often decide the route in Reigate and Banstead are listed below, taken from our Reigate and Banstead area page. Each one is a reason to confirm the address on Reigate and Banstead's constraints map before relying on permitted development.
- Green Belt. Most of the borough outside Reigate, Redhill, Banstead and Horley is Green Belt, including land around Kingswood, Chipstead, Merstham, Salfords and the North Downs. Source
- Surrey Hills National Landscape. The North Downs above Reigate, including Reigate Hill, Colley Hill and the scarp towards Merstham, fall within the Surrey Hills National Landscape (formerly the Surrey Hills Area of Outstanding Natural Beauty). Source
- Conservation areas. Reigate town centre, Banstead, Chipstead, Kingswood and Merstham are among the borough's conservation areas. Source
- River Mole and Redhill Brook flood risk. The River Mole and its tributaries run through Horley, Salfords and Sidlow, and the Redhill Brook drains Redhill and Earlswood towards the Mole. Source
- Listed buildings. Reigate town centre, Banstead, Chipstead, Merstham and the villages contain many listed houses, cottages and churches. Source
The council's two-storey side extension rules on a 1930s semi
The council's Householder Extensions and Alterations SPG (March 2004) sets out two approaches for a two-storey side extension. The first sets the extension significantly back from the main front wall with a reduced ridge line, so it reads clearly as subservient; the SPG says this suits all types of property and that materials do not need to match exactly. The second has no set-back, so the extension looks like part of the original house; it is suitable for some detached houses with large gardens, but materials are very hard to match and the extension can fill the plot.
To avoid a terracing effect, the SPG says retaining a one metre gap between the extended house and the boundary will normally be required, and that two-storey front extensions are rarely acceptable. Where plots are large and houses are already separated by gaps, as in Residential Areas of Special Character, it asks for a greater distance than 1 m. It also asks applicants to consider any loss of car parking, and a garage conversion has to include alternative parking.
Rear extensions, and Kingswood and Chipstead-style plots
For a two-storey rear extension the SPG illustrates an unacceptable example by three tests: overshadowing, because it fails the 45-degree test; direct overlooking of the neighbour's principal windows and immediate garden; and a dominant appearance from the neighbour's side. Its acceptable example sits further from the boundary.
The 2021 Local Character and Distinctiveness Design Guide adds guidance for the Residential Areas of Special Character, naming Kingswood among them. There no part of a development should be forward of the front building line, eaves and ridge heights should match appropriate neighbours and are expected to be shown on street scene drawings, and slate is not suitable: plain tiles of local clay, or matching colour, are expected. Roofs should follow the pitch, eaves height and ridge height of the road.
Green Belt houses
Policy NHE5 of the Development Management Plan allows extensions to a Green Belt building where they are not disproportionate to the original building, meaning the house as built or as it stood on 1 July 1948, whichever is later. A second storey adds footprint, floor area, massing and height, all of which the policy weighs, so on a house already extended we establish the original building first.
What Reigate and Banstead planning officers look for
On the 1930s semis in Nork, Banstead, Earlswood and Merstham they tend to look for two-storey side extensions set back from the front wall and below the main ridge, a gap kept to the side boundary so the pair does not read as a terrace, and rear extensions that pass the 45-degree test to the neighbour's nearest habitable window. In the Green Belt officers usually measure the extension against the original dwelling by floorspace or volume and treat outbuildings more strictly. Common refusal reasons are full-width box dormers, side extensions that create a terracing effect, and disproportionate additions in the Green Belt. The council offers a paid pre-application service.
Fees and timelines
Reigate and Banstead 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
- Reigate and Banstead Borough Council: Householder Extensions and Alterations SPG (March 2004)
- Reigate and Banstead Borough Council: Local Character and Distinctiveness Design Guide SPD (June 2021)
- Reigate and Banstead Borough Council: Development Management Plan, Policy NHE5
- 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.
- Reigate and Banstead Borough Council: planning: the council's own constraints map, validation checklist and pre-application service.
