Double storey extension drawings in London
Our double storey extension planning drawings for London homes start from £995, with the measured survey included. A two-storey rear extension under permitted development may not extend beyond the original rear wall by more than 3 metres, and a longer or closer one needs a householder application. London councils granted 86% of householder decisions in the four quarters to 2026 Q2 (our analysis of MHCLG planning application statistics, table PS2).
Fixed fee from £795 drawings + £200 survey (£995 total) · all prices
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What stops a two-storey extension being permitted development
Three limits decide it. An extension of more than one storey must not extend beyond the rear wall of the original house by more than 3 metres, and must not be within 7 metres of any boundary of the curtilage opposite the rear wall. Where any part is within 2 metres of the boundary, its eaves must not exceed 3 metres (General Permitted Development Order, Schedule 2 Part 1).
On article 2(3) land, which includes conservation areas, the same Part does not permit cladding, extensions beyond a side elevation wall, or an extension of more than one storey beyond the rear wall. The permitted development glossary entry and the conservation area extension guide cover what follows.
When a full application is needed
A scheme that breaks any of those limits goes in as a householder application. London councils made 23,967 householder decisions in the four quarters to 2026 Q2 and granted 86% of them, prior approvals included (our analysis of MHCLG planning application statistics, table PS2). Individual boroughs vary, so the council pages for double storey extensions show each borough's own figures.
The council fee for a householder application is £548 from 1 April 2026. Our planning permission guide for double storey extensions walks through the decision.
London councils made 23,967 householder decisions in the four quarters to 2026 Q2 and granted 86% of them, prior approvals included (our analysis of MHCLG planning application statistics, table PS2).
What the drawing set contains
A two-storey extension needs a survey of the house, existing and proposed plans for both floors, elevations, sections and a block plan, and, for Building Regulations, the structural calculations that show how the upper floor is held up. Our fixed fee for double storey extension planning drawings starts at £995. The pricing page lists the other fixed fees, and the two-storey rear extension plans topic and two-storey side extension plans topic cover those two forms.
After planning: the structure and the neighbours
Planning consent does not settle how the extension is built. The extension of a building is building work under regulation 3 of the Building Regulations 2010, and Part A of Schedule 1 requires the building to carry its dead, imposed and wind loads safely to the ground. A second storey adds weight to new foundations and to openings in the old rear wall, which is why the Building Regulations stage needs structural calculations from a named, insured engineer, priced separately.
Building on a shared wall, or digging foundations near next door, also brings in the Party Wall etc. Act 1996. A notice for work on a party structure goes to the neighbour at least two months before that work begins (section 3), and a notice for excavating within 3 metres of their building and below its foundations at least one month before digging starts (section 6). The party wall notices and drawings page explains the procedure.
A sample planning set, sheet by sheet
Sample drawings of an invented house, not a client project: a two-storey side extension to a 1930s-style semi-detached house, drawn in our own Revit model. A real application also needs a location plan on licensed Ordnance Survey mapping, left out here because the house and its street are invented. Open any sheet to see it full size.
PL-01 Existing and proposed block plans The extension against the side boundary, and the side passage left open.
PL-02 Existing ground and first floor plans The house as it stands: the baseline every proposed change is measured against.
PL-03 Existing front and rear elevations The heights and materials the extension has to match.
PL-04 Proposed ground floor plan The new study and kitchen, the steel beam over the new opening, and the passage kept to the garden.
PL-05 Proposed first floor plan The bedroom and en-suite the extension adds upstairs.
PL-06 Existing and proposed roof plans The hipped roof carried over the extension, its ridge kept below the main ridge.
PL-07 Proposed front and rear elevations Matching brick, render and tiles, and the set-back from the front wall that keeps the extension subordinate.
PL-08 Existing and proposed side elevations The flank wall that faces the boundary: no new windows overlooking the neighbour.
PL-09 Proposed section A-A Floor and ceiling levels through the extension, against the house.
PL-10 Proposed section B-B A cut across the house and the extension, where the old flank wall opens under the new beam.
PL-11 Proposed 3D view How the extension reads from the street. Illustrative, not a submission drawing.
Sources
Every figure on this page, where it comes from and a link to the original.
| Figure | Source | Link |
|---|---|---|
| £995 | DrawingsDirect starting fixed fee for a double-storey extension | drawingsdirect.co.uk |
| 3 metres | GPDO 2015 Sch 2 Pt 1 Class A.1(h)(i): an extension of more than one storey must not extend beyond the rear wall of the original house by more than 3 metres (source wording: "by more than 3 metres") | www.legislation.gov.uk |
| 7 metres | GPDO 2015 Sch 2 Pt 1 Class A.1(h)(ii): an extension of more than one storey must not be within 7 metres of any boundary of the curtilage opposite the rear wall (source wording: "be within 7 metres of any boundary of the curtilage") | www.legislation.gov.uk |
| 2 metres | GPDO 2015 Sch 2 Pt 1 Class A.1(i): where the enlarged part is within 2 metres of the curtilage boundary, its eaves must not exceed 3 metres (source wording: 2 metres) | www.legislation.gov.uk |
| article 2(3) land | GPDO 2015 Sch 2 Pt 1 Class A.2: on article 2(3) land (which includes conservation areas) Class A does not permit cladding, extensions beyond a side elevation wall, or an extension of more than one storey beyond the rear wall (source wording: "have more than a single storey and extend beyond the rear wall of the original dwellinghouse") | www.legislation.gov.uk |
| 23,967 | Our analysis of MHCLG planning application statistics, table PS2 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| 86% | Our analysis of MHCLG planning application statistics, table PS2 (district open data table) (released 24 Sep 2026, quarters to 2026 Q2) | www.gov.uk |
| £548 | Fees for planning applications in England from 1 April 2026 (MHCLG, SI 2012/2920 as annually indexed), category 6(1): householder application for the enlargement, improvement or alteration of a single dwellinghouse (source wording: £548) | assets.publishing.service.gov.uk |
| two months | Party Wall etc. Act 1996 s3(2)(a): a party structure notice must be served at least two months before the date on which the proposed work will begin (source wording: "at least two months before") | www.legislation.gov.uk |
| one month | Party Wall etc. Act 1996 s6(5): notice of adjacent excavation must be served at least one month before beginning to excavate (source wording: "at least one month before beginning to excavate") | www.legislation.gov.uk |
Questions people ask
How far can a double storey extension go at the back?
Can I build a double storey extension in a conservation area without an application?
How much do double storey extension drawings cost?
Photographs: Derek Harper (CC BY-SA 2.0).
