Loft conversion in Penge
A loft conversion in Penge is decided by Bromley council, and in the latest four quarters it granted 79% of its householder applications. Whether you need an application at all depends on how much roof space you add. Our drawings for a rear dormer start at £695, and they work for either route.
Fixed fee from £495 drawings + £200 survey (£695 total) · all prices
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Loft conversion, loft extension, loft renovation: what the council sees
People in SE20 search for a loft conversion, a loft extension, a renovation or a dormer, and the council treats them alike. What it assesses is the physical change to the roof: the volume added, where the new walls and windows sit, and what the street will see.
A renovation that only insulates and boards the existing roof space, with no change to the outside, is largely a Building Regulations matter. Add a dormer, a rear gable or a raised ridge and the planning rules apply as well.
When no planning application is needed
Permitted development allows an addition of up to 40 cubic metres to a terrace house, and up to 50 cubic metres to any other house. The first job is to establish whether your house counts as a terrace and what earlier owners have already added.
The addition must be set back not less than 0.2 metres from the eaves, and the other Class B conditions in the General Permitted Development Order apply too. A conservation area, a flat or an Article 4 direction takes the right away.
Our analysis of the MHCLG Planning Data Platform datasets (bulk snapshot retrieved 19 Oct 2026) finds 73 live conservation-area entries on the national register for Bromley. Ask the council's map whether your road is one of them.
Our analysis of the MHCLG Planning Data Platform datasets (bulk snapshot retrieved 19 Oct 2026) finds 73 live conservation-area entries on the national register for Bromley.
Bromley's record on householder cases
In our analysis of MHCLG planning application statistics, table PS2, Bromley made 1,609 householder decisions across the four quarters to 2026 Q2 and granted 79%. Of the applications that were not prior approvals, 90% were decided within 8 weeks.
Householder appeals add another angle. In our analysis of the Planning Inspectorate casework database (release 2609), 563 householder appeals in Bromley were decided between 2021 and 2026, and 37% were allowed. Both sets of figures cover all householder work, not only lofts, and they describe the past.
Bromley also decided 1,030 certificates of lawful development of all kinds across the eight quarters from 2024 Q3 to 2026 Q2, according to our analysis of table PS1. Plenty of owners take that route for a loft that fits the limits.
Pick the roof form before the drawings
A rear dormer is the usual starting point, drawn from £695 as a fixed fee. If you want a side-to-side gain on a hipped roof, look at hip-to-gable loft conversion drawings. Our dormer loft conversion drawings page sets out the rear and L-shaped forms.
For the wider London picture, our loft conversion drawings hub explains the drawings and the routes. Drawings arrive within 7 days and redraws are free until the council or building control is satisfied.
Sources
Every figure on this page, where it comes from and a link to the original.
| Figure | Source | Link |
|---|---|---|
| £695 | DrawingsDirect starting fixed fee for rear dormer loft conversion permitted development drawings, from the published price list | drawingsdirect.co.uk |
| 40 cubic metres | GPDO 2015 Sch 2 Pt 1 Class B.1(d)(i): roof additions may add up to 40 cubic metres to the roof space of a terrace house (source wording: "40 cubic metres in the case of a terrace house") | www.legislation.gov.uk |
| 50 cubic metres | GPDO 2015 Sch 2 Pt 1 Class B.1(d)(ii): roof additions may add up to 50 cubic metres to the roof space of any other house (source wording: "50 cubic metres in any other case") | www.legislation.gov.uk |
| 1,609 | Our analysis of MHCLG planning application statistics, table PS2 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| 79% | Our analysis of MHCLG planning application statistics, table PS2 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| 90% | Our analysis of MHCLG planning application statistics, table PS2 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| 563 | Our analysis of Planning Inspectorate Casework Database (released 1 Oct 2026 (Casework Database 2609)) | www.gov.uk |
| 37% | Our analysis of Planning Inspectorate Casework Database (released 1 Oct 2026 (Casework Database 2609)) | www.gov.uk |
| 73 | Our analysis of MHCLG Planning Data Platform conservation-area and article-4-direction datasets (bulk snapshot retrieved 19 Oct 2026) | www.planning.data.gov.uk |
| 1,030 | Our analysis of MHCLG planning application statistics, table PS1 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
Questions people ask
Do I need planning permission for a loft extension in Penge?
Can I convert a loft in Penge without changing the outside?
Does a dormer loft conversion in Penge cost more to draw?
Photographs: GRALISTAIR (CC BY-SA 4.0); GRALISTAIR (CC BY-SA 4.0).
