
Side Return Extension Drawings in Brook Green W6
Fixed-fee, MCIAT-chartered side return extension drawings for Brook Green (W6) homeowners — London Borough of Hammersmith & Fulham validation and local constraints handled from the start.
Brook Green in W6 is a sought-after enclave of large Victorian terraces and Edwardian mansion blocks in the green space between Hammersmith and Kensington. Families here typically extend at the rear or into the side return, convert generous lofts, or reconfigure mansion flats, so most of our drawings support space-making projects on characterful period homes.
The Brook Green conservation area and neighbouring designations mean roof alterations, front elevations and materials are all assessed against a strikingly consistent streetscape. We detail schemes to sit comfortably within that grain and present them the way Hammersmith and Fulham's officers expect, which keeps sensitive extensions and loft conversions moving smoothly towards approval.


Planning in Brook Green (W6): what to know before you apply
There is no published householder Article 4 direction we depend on for Brook Green, but the Brook Green conservation area constrains permitted development on roofs and principal elevations. Matching red-brick detail, respecting the scale of the terraces, and checking for protected street trees are the usual design limits on rear and roof works.
Typical Brook Green housing stock
Brook Green is a leafy pocket of large Victorian terraces and red-brick Edwardian mansion blocks set between Hammersmith and Kensington. The generous houses lend themselves to full-width rear extensions, side returns and loft conversions, while the mansion blocks generate careful internal reconfigurations and flat conversions that suit family life in W6.
Streets we regularly draw for in Brook Green
Yeldham Road · Winslow Road · Sussex Place · Playfair Street
What W6 is actually built of
Measured from 388 classified residential buildings in W6, not from a description of the area.
Brook Green W6 housing mix
Residential building form across the W6 postcode district, from 388 classified buildings.
| Attached on more than one side | 80% |
|---|---|
| Attached on one side | 17% |
| Detached | 3% |
| Median building footprint | 63 m² |
| Addresses per buildingAbove about 2 means flats and maisonettes dominate | 2.68 |
| Buildings classified | 388 |
Source: Ordnance Survey National Geographic Database (derived statistics). Contains OS data © Crown copyright and database right 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. Extracted 2026-08-17.
Side Return Extension Drawings for Brook Green (W6) homes: the package and the process
A side return is a structural drawing as much as a planning one. Removing the original flank wall to open the kitchen into the infill needs a beam and a padstone detail, and the new roof has to be drawn where it meets both the existing rear elevation and the boundary wall.
The boundary is the sensitive line. The drawings set out where the new wall sits relative to it, how the roof drains without discharging next door, and where rooflights fall so the officer can see the room is lit without overlooking. That detail is also what your party wall surveyor will ask for.
The extension only exists where the alley does. Mid-terrace and end-of-terrace houses with a rear outrigger are the classic case; a semi with a flank path is a different scheme with different boundary questions; and a detached house has no side return to infill at all.
Do I need planning permission for a side return extension in London?
Permitted development rights for side extensions are narrower than for rear extensions: they generally cap the extension at a single storey, restrict its width to no more than half the width of the original house, and limit its height. In practice, a full-depth side return running the length of a Victorian or Edwardian terrace usually exceeds one or more of these limits, so most side return projects are drawn and submitted as a full householder planning application.
Conservation area status and Article 4 directions, common across inner London terraces, remove permitted development rights for side extensions entirely in many streets, reinforcing the need for a planning application. We check your property's status before drawing.
What does a side return extension involve?
A side return infills the alley at ground floor level, structurally opening the original flank wall of the kitchen into the new space so the two areas read as one room. Unlike a rear extension, which is bounded on three sides by your own garden, a side return is bounded on one long side by the neighbouring property, which shapes almost every decision in the design, from where the roof glazing sits to how deep the new foundations need to go.
- New flank wall built out to align with the rear of the house, following the boundary line
- Original external wall between kitchen and alley opened up and supported on a steel or glulam beam
- Roof over the new space either glazed in full, glazed in a strip along the boundary for a 'light well' effect, or pitched and tiled to match the main roof
- Kitchen re-planned across the combined footprint, often incorporating an island once the room widens
Will I need a Party Wall Agreement for a side return extension?
Almost certainly. Because the new side wall is built on or immediately against the boundary with the neighbouring property, the Party Wall etc. Act 1996 applies, and your neighbour must be formally notified before work starts. We prepare the drawings and dimensions your Party Wall surveyor needs, and time the notice period so it runs alongside, rather than after, your planning application.
| Package | What it covers | Typical fee |
|---|---|---|
| Side return, planning only | Full householder planning application drawings for the infill | Full Planning pack ~£1,600–£2,400 |
| Side return, planning + Building Regulations | Adds structural calculations, Party Wall drawings and construction detail | Planning + Building Regs pack ~£2,200–£3,850 |
| Side return + rear extension (wraparound) | Combines both extensions into one L-shaped ground floor | see Wraparound Extension Drawings |
| Measured survey only | A measured existing floor-plan set for your own architect, surveyor or builder | from £450 |

Side Return Extension Drawings in Brook Green W6 — FAQs
How much does a side return extension cost to design in London?+
Can I build a side return under permitted development?+
When do I need to serve Party Wall notice on my neighbour?+
Do I need an architect for a side return extension?+
How long does a side return extension take to design and approve?+
Do I need planning permission for a side-return extension in Hammersmith & Fulham?+
Will I need a Basement Impact Assessment for a basement in Hammersmith & Fulham?+
What is special about the Peterborough Estate 'Lion houses'?+
How long does Hammersmith & Fulham take to decide?+
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