House extension drawings in Barnet
A house extension in Barnet takes one of three routes: permitted development, prior approval or a householder planning application. On the last of these the council granted 80% of the 1,361 householder decisions it made in the four quarters to 2026 Q2 (our analysis of MHCLG planning application statistics, table PS2). DrawingsDirect draws rear extensions from £695.
Fixed fee from £495 drawings + £200 survey (£695 total) · all prices
Prefer to talk it through?
Which route fits your Barnet extension: permitted development or a planning application?
Many houses can extend at the back without a planning application, within limits set by the General Permitted Development Order. A single-storey rear extension on a house that is not detached can go back 3 metres. A larger home extension, which needs the council's prior approval, can reach 6 metres on the same type of house (GPDO 2015, Schedule 2, Part 1, Class A, on legislation.gov.uk).
Anything deeper, taller or wider than those limits needs a full householder application. Our permitted development explainer lists what the rules cover, and the prior approval guide walks through the larger-extension route.
What Barnet's own decisions show
Barnet decided 1,361 householder applications in the four quarters to 2026 Q2 and granted 80% of them (our analysis of MHCLG planning application statistics, table PS2).
Larger home extension notifications need reading with care. Over the eight quarters to 2026 Q2 Barnet found prior approval was required on 242 of them and granted 13% of those (our analysis of MHCLG planning application statistics, table PS1). Notifications where the council decided prior approval was not required, which lets the extension go ahead, are a separate outcome and sit outside that 13%.
So the 13% is not the share of all larger extensions that Barnet stops. It does show that when the council takes a closer look at a deep rear extension, refusal is the usual result, so we check the neighbours' side of the scheme before choosing that route. We cannot promise any result.
The government's national planning data register holds 16 conservation-area entries for Barnet (our analysis of the MHCLG Planning Data Platform conservation-area dataset).
Council fees for a Barnet extension
A householder application for alterations or extensions to a single dwellinghouse costs £548 in statutory fee from 1 April 2026. A prior approval for a larger rear extension costs £249. Both are paid to the council when the application goes in.
Our drawings are priced separately: rear extension drawings start from £695. The rear extension cost guide breaks down building costs, and the pricing page lists every fixed fee.
Conservation areas in the borough
The government's national planning data register holds 16 conservation-area entries for Barnet (our analysis of the MHCLG Planning Data Platform conservation-area dataset). Inside one, permitted development rights are narrower and the council looks harder at materials, roofline and street frontage.
Check your road on Barnet Council's conservation area map before you design anything. Our conservation area extension rules guide covers what changes.
Getting drawings started
Tell us the address and the room you want to add. We look at the planning history, advise on the route, and quote a fixed fee. If the house has never been measured we begin with a measured building survey, then draw the existing and proposed plans on the same base. Our rear extension drawings page shows what the set contains.
Sources
Every figure on this page, where it comes from and a link to the original.
| Figure | Source | Link |
|---|---|---|
| 1,361 | Our analysis of MHCLG planning application statistics, table PS2 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| 80% | Our analysis of MHCLG planning application statistics, table PS2 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| 242 | Our analysis of MHCLG planning application statistics, table PS1 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| 13% | Our analysis of MHCLG planning application statistics, table PS1 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| 16 | Our analysis of MHCLG Planning Data Platform conservation-area and article-4-direction datasets (bulk snapshot retrieved 14 Aug 2026) | www.planning.data.gov.uk |
| 3 metres | GPDO 2015 Sch 2 Pt 1 Class A.1(f)(i): single-storey rear extension max depth, house other than detached (source wording: 3 metres) | www.legislation.gov.uk |
| 6 metres | GPDO 2015 Sch 2 Pt 1 Class A.1(g): larger home extension (prior approval, A.4) max depth, house other than detached (source wording: 6 metres) | www.legislation.gov.uk |
| £548 | Statutory fee from 1 April 2026, SI 2012/2920 Sch 1 Pt 2 category 6(1): householder application for alterations or extensions to a single dwellinghouse | assets.publishing.service.gov.uk |
| £249 | Statutory fee from 1 April 2026: prior approval for a householder larger rear extension (GPDO Part 1 Class A) | assets.publishing.service.gov.uk |
| £695 | DrawingsDirect starting fixed fee for rear extension drawings, from the published price list | drawingsdirect.co.uk |
Questions people ask
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Photographs: David Howard (CC BY-SA 2.0); Derek Harper (CC BY-SA 2.0).
