Four homes in ten here are flats
Start with the number that catches people out. The 2021 Census counted 162,300 dwellings in the borough, and 41% of them are flats. Between 2011 and 2021 about 13,000 homes were added, mostly flats.
If you own the top flat, you can't lean on permitted development. The national rules for roof enlargements apply to houses only, and the legal definition of a house leaves out any building containing flats. So a dormer on a converted house in Thornton Heath or South Norwood needs a full planning application, and the freeholder will want a say too. Sort out who owns the roof space before you pay an architect anything.
The rest are houses, 24% semi-detached, 23% terraced and 12% detached. That mix is where most Croydon lofts get built.
Which part of the borough you're in
The north sits on London Clay and has a lot of Victorian and Edwardian terraces. The council's own character study picks out Broad Green and Selhurst, where terraces dominate east of Mitcham Road, and the narrow streets of small houses between East Croydon station and the East India Estate in Addiscombe.
Go south and the houses get bigger and later. Coulsdon has interwar Arts and Crafts detached houses on big plots around Hartley Downs, with planned semi estates near Rickman Hill and Marlpit Lane. New Addington was begun in 1935 as a garden village and had 1,023 houses before the war, mostly semis set out in crescents. On a crescent of matching roofs, one altered hip stands out from the street.
Here is how each type of conversion tends to suit those houses, starting with the semis.
Hip to gable. The obvious move on an interwar semi in Coulsdon or New Addington, where the hipped end leaves little usable space. Inside a conservation area, though, the council's guidance says hip to gable work is unlikely to be approved.
Read our full guide: Hip-to-Gable Loft Conversions: What It Involves and Which Houses It Suits →
Rear dormer. Right for most terraces in Selhurst, Broad Green and Addiscombe. Outside a conservation area it usually goes ahead as permitted development, provided the house is still a single house and not flats.
L-shaped dormer. Victorian terraces with a back addition can take a second dormer over the outrigger. A good way to fit a shower room without losing the bedroom.
Rooflights only. Often the only realistic option on the steep roofs of the Norbury Estate or a big Upper Norwood villa. Croydon's conservation guidance asks for rooflights that sit flush with the slope, and heritage-style ones on older buildings.
Mansard. Nearly always a planning application. It changes the whole roof shape, so it tends to suit a terrace where neighbours have already done the same rather than a street of untouched rooflines.
Extra bedroom. The usual reason for doing it. A third floor means a protected escape route down through the house, so check the quote covers fire doors on every room off the stairs.
En-suite. On a terrace, put it above the existing bathroom if you can, so the soil pipe has a short run. Moving it to the front of the house adds cost quickly.
Home office. Works well in the big detached houses further south, where a gable or rear dormer gives you a proper desk wall. Have the data cable run up while the walls are open.
Read our full guide: Loft Home-Office Conversion: What Works Well Up There and What to Specify →
Planning. In Croydon three questions decide it. Is the house in one of the 21 conservation areas? Is it flats? And, if you're on Chatsworth Road, have you read the Article 4 direction? Get those answered before any drawings.
Cost. No price here, because a 1960s house at Fieldway and a slate Victorian roof in Addiscombe are different jobs.
Chatsworth Road, Norbury and the protected streets
Croydon has 21 conservation areas, from Central Croydon and the Croydon Minster area out to the Webb Estate in Purley, Bradmore Green and Addington Village. In all of them, any dormer or roof enlargement needs planning permission, on the back slope as well as the front. The council's 2013 conservation guidance is blunt. Roof extensions visible from the road are unlikely to be accepted, and hip to gable is unlikely to get permission at all.
Chatsworth Road goes further. Its Article 4 direction, in force since 21 January 2016, removes the right to make any alteration to the roof of a house there. That includes rooflights, which elsewhere you could normally fit without asking.
The Norbury Estate was one of the London County Council's first cottage estates and the first it built outside its own boundary, with 642 homes up by 1920. The terraces have steep slate and clay tile roofs with gables facing the street, and the council's appraisal says dormers on roofs seen from the road will be resisted. Re-roofing has to be natural slate or plain clay tile, not concrete.
Local Heritage Areas, such as Bingham Road or the Portland Road Terraces, are different. They don't remove any permitted development rights. They only count if your plans need permission anyway.
Building control is Croydon Building Control at Bernard Weatherill House on Mint Walk, unless your builder uses an approved inspector. You can search past applications on your street through the council's online planning register.
Where these facts come from
- Croydon Council: conservation areas
- Croydon Council: Conservation Area General Guidance (2013)
- Croydon Council: Chatsworth Road Article 4 confirmation
- Croydon Council: Norbury Estate appraisal
- Croydon Council: Local Heritage Areas
- Croydon Council: Borough Character Appraisal
- Croydon housing needs assessment 2023 (Census 2021 mix)
- Croydon Council: contact building control
- GPDO 2015 article 2 (definition of dwellinghouse)
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Questions people in Croydon ask
I own the top flat in a converted house in South Norwood. Can I go into the loft?
Possibly, but not under permitted development, because those rights don't cover flats. You need planning permission, building regulations approval and, unless you own the freehold, the freeholder's written consent to use the roof space.
We live on Chatsworth Road. Can we at least put in rooflights?
Not without asking. The Article 4 direction there removes the right to make any roof alteration to a house, so rooflights need planning permission like everything else.
Our road is a Local Heritage Area, not a conservation area. Does that stop a rear dormer?
No. Local Heritage Area status doesn't touch permitted development, so a rear dormer that fits within the national limits can still go ahead. If you need a planning application for other reasons, the council will weigh the character of the area.
Can I convert one half of a pair of 1930s semis to a gable end?
Outside a conservation area, usually yes under permitted development. Inside one it needs permission, and the council's guidance says hip to gable work there is unlikely to be approved. Check your street's status first.