Croydon, London
Dormer loft conversion drawings in Croydon
Dormer loft conversion drawings for a Croydon house start at £695 including VAT. Croydon has no measured dormer rule in its published guidance, so the route depends on where you live: the borough has 19 conservation areas, and inside one a dormer needs planning permission.
From £695 (VAT included)
- MCIAT chartered
- £2m PI insured
- LABC Partnered
- Fixed fees, VAT included
Request a fixed quote
How Croydon treats a dormer on a house
We found no council dormer rule with a measured value in Croydon's published planning documents, so we do not quote one. The design is assessed against the Croydon Local Plan 2018 and, where it applies, the Conservation Areas General Guidance SPD.
The conservation area guidance is the one that bites. It is the council's guidance for its designated areas, and a dormer there is judged against the character of the street it sits in. Outside those areas, the national permitted development rules do most of the work.
That puts the weight on the site visit and the street. We look at the roofs along the road, at what the neighbours have already built, and at how visible the rear slope is from the garden and from behind. A dormer that matches what is already there is the easiest to support.
Materials follow the same principle. Under permitted development the exterior finish must be Exterior materials similar in appearance to the existing house, and upper-floor side windows must be Upper-floor side windows obscure-glazed and non-opening below 1.7 m above floor. We choose tile-hanging, zinc or cladding by looking at the house and its neighbours, not by preference.
Local figures for Croydon
| Measure | Value | Period | Source |
|---|---|---|---|
| Conservation areas | 19 named conservation areas published by the council | — | planning.data.gov.uk |
| Listed building entries | 180 list entries (Historic England, within the LPA boundary) | — | planning.data.gov.uk |
| Householder decisions | 786 decisions | 1 July 2025 - 30 June 2026 | assets.publishing.service.gov.uk |
| Householder applications granted | 86.6 % | 1 July 2025 - 30 June 2026 | assets.publishing.service.gov.uk |
| Householder applications decided in time | 94.4 % decided within 8 weeks or an agreed extended period | 1 July 2025 - 30 June 2026 | assets.publishing.service.gov.uk |
| Green Belt share of the council area | 25 % of council area covered by green-belt polygons | — | planning.data.gov.uk |
| Supplementary planning document | Conservation Areas General Guidance SPD | — | croydon.gov.uk |
| GPDO 2015 Sch 2 Pt 1 Class B, para B.1(d) | 40 m³ (terrace house) / 50 m³ (any other house) additional roof volume | — | legislation.gov.uk |
| Class B, para B.1(c) | No enlargement beyond the plane of a roof slope that forms the principal elevation and fronts a highway | — | legislation.gov.uk |
| Class B, para B.1(f) | Class B roof enlargements are not permitted development on article 2(3) land | — | legislation.gov.uk |
A blank value means the figure has not been published, not that there are none. Check your own address with the council.
Householder applications by street in Croydon
| Street | Applications | Approved |
|---|---|---|
| Devonshire Way | 35 | 56% |
| Mount Park Avenue | 30 | 79% |
| Farley Road | 28 | 85% |
| Chaldon Way | 25 | 92% |
| Norbury Hill | 24 | 82% |
| Pollards Hill South | 24 | 63% |
| Bradmore Way | 23 | 87% |
| Woodcote Valley Road | 23 | 76% |
| Littleheath Road | 22 | 64% |
| Valley Road | 22 | 64% |
| Shirley Road | 21 | 74% |
| Upfield | 20 | 65% |
| Arkwright Road | 19 | 83% |
| Georgia Road | 19 | 63% |
| Caterham Drive | 18 | 78% |
Loft enlargement in section: the permitted development limits
A dormer on the rear slope, with the limits that decide whether it needs planning permission.
- A · Extra roof volume allowed
- 40 m³ (terrace house) / 50 m³ (any other house) additional roof volume
- B · Set-back from the eaves
- Original eaves maintained; enlargement set at least 0.2 m from the eaves measured up the roof slope, so far as practicable (not required for hip-to-gable or roofs joining a rear/side extension)
- C · Height limit
- No part higher than the highest part of the existing roof
Conservation areas, green belt and listed houses in Croydon
Croydon has 19 conservation areas, and Historic England records 180 listed entries within the borough. In a conservation area a roof enlargement is not permitted development. A listed house needs listed building consent in addition.
About 25 per cent of the borough is covered by green-belt designation. A house inside it can face limits on later extensions that a house outside would not, so we ask about your wider plans before fixing the size of the dormer.
Away from those designations, the permitted development volume is 40 m³ (terrace house) / 50 m³ (any other house) additional roof volume. The dormer must also keep off any roof slope that fronts a highway.
Croydon householder decisions
Croydon decided 786 householder applications in its latest published year and granted 86.6 per cent. 94.4 per cent were decided within the statutory period or an agreed extension.
Those figures cover every householder project in the borough and do not describe any one roof. We use them to plan the programme, so that a builder is booked after the likely decision date, not before it.
When the design stays inside permitted development, a Lawful Development Certificate gives written confirmation without a full application. We advise which route fits when we know the address. If a listed house or a conservation area is involved, we say so at the quote stage, because the application then needs more drawings and a longer programme than a straightforward householder case.
What our Croydon dormer loft conversion drawings include
The set covers existing and proposed floor plans, the stair, the roof in section with the dormer and its build-up, and every elevation, together with location and block plans.
The stair follows the loft rule in the building regulations: Loft conversions where 2.0 m cannot be achieved: 1.9 m at the centre of the stair, 1.8 m at the side (half width). The new storey needs a protected escape route, which the rule gives as New storey above 4.5 m by loft conversion: protect the full escape route with fire-resisting doors (min E 20) and partitions (min REI 30). The dormer roof has an energy target as well: New elements in existing dwellings, limiting U-values W/(m²·K): roof 0.15, wall 0.18, floor 0.18, windows 1.4 (or WER Band B), doors 1.4.
The price is £695 including VAT, fixed before you commit. A second MCIAT chartered architectural technologist checks the set, and we redraw at no charge if the council asks for changes.
Related drawings in Croydon and the councils nearby
A simpler roof may need only rooflights: see Velux loft conversion drawings in Croydon. The general loft route is on the loft conversion drawings in Croydon page, and a wider form is covered by L-shaped dormer drawings in Croydon.
Neighbouring councils differ: dormer loft conversion drawings in Bromley, in Sutton and in Lambeth. The overview is architectural drawings in Croydon, and the national rules are on the dormer loft conversion drawings hub.
What you receive
Related pages
Other services in Croydon
Questions
Does Croydon have a rule on dormer size?
We found no measured dormer rule in the council's published guidance. The design is judged against the local plan, and in a conservation area against the area's guidance.
Do I need planning permission for a dormer in a Croydon conservation area?
Yes. The permitted development right for roof enlargements does not apply there, and Croydon has 19 conservation areas.
Can I use permitted development for a Croydon dormer?
If the house keeps its rights, the dormer stays off the road-facing slope and the volume allowance is respected, yes. A Lawful Development Certificate can confirm it.
What do dormer loft conversion drawings cost in Croydon?
From £695 including VAT, fixed up front. Council fees are separate.
Sources and dates
- planning.data.gov.uk, retrieved
- planning.data.gov.uk, retrieved
- assets.publishing.service.gov.uk, retrieved
- planning.data.gov.uk, retrieved
- croydon.gov.uk, retrieved
- legislation.gov.uk, retrieved
- croydon.gov.uk, retrieved
- gov.uk, retrieved
- gov.uk, retrieved
- gov.uk, retrieved
- Contains public sector information licensed under the Open Government Licence v3.0.
- Contains OS data © Crown copyright and database right 2026.
- Contains HM Land Registry data © Crown copyright and database right 2026. This data is licensed under the Open Government Licence v3.0.
- Contains Historic England data © Historic England 2026. Contains Ordnance Survey data © Crown copyright and database right 2026.
Tell us about your property.
We check the constraints, then send a fixed fee. Messages before 3pm get a reply the same working day.