MCIAT chartered drawings · Fixed fees across all 33 London boroughs
[email protected]020 7864 7245WhatsApp

Free 2026 London Planning Report — Side Return Extension Drawings in Herne Hill SE24

Single-storey rear extension behind an Edwardian terrace in Herne Hill SE24, London Borough of Lambeth
Herne Hill · SE24 · Lambeth

Side Return Extension Drawings in Herne Hill SE24

Fixed-fee, MCIAT-chartered side return extension drawings for Herne Hill (SE24) homeowners — London Borough of Lambeth validation and local constraints handled from the start.

Free Herne Hill planning assessment

Tell us your Herne Hill (SE24) address and project. A fixed quote and free planning appraisal land within one working day.

No obligation · No spam · Reply within 1 working day

Herne Hill (SE24) straddles the Lambeth–Southwark boundary around Brockwell Park, with its Lambeth side made up of desirable late-Victorian and Edwardian streets — including the Poets' Corner terraces off Railton Road. Rear and loft projects are the staple here, shaped by the conservation areas that cover much of the neighbourhood. (The Stradella Road conservation area lies just across the boundary in Southwark, so properties there answer to a different council.)

Lambeth's Brockwell Park and Herne Hill conservation areas closely control frontages and rooflines around the park and the Poets' Corner streets, and the low ground near the culverted River Effra brings flood-risk considerations. We check where a Herne Hill property sits relative to those designations — and which side of the borough boundary it falls — before recommending a permitted-development or full-application route.

Single-storey rear extension behind an Edwardian terrace in Herne Hill SE24, London Borough of Lambeth
Isometric illustration of a Herne Hill SE24 home side return extension drawings design
Proposed floor plan
Herne Hill SE24

Planning in Herne Hill (SE24): what to know before you apply

SE24 has no householder Article 4 direction, so many Herne Hill houses retain permitted development rights for rear and loft work — but Lambeth's Brockwell Park and Herne Hill conservation areas are the exceptions, controlling frontages and rooflines around the park and the Poets' Corner streets, and low-lying parts near the old River Effra carry flood-risk considerations. SE24 straddles the Lambeth–Southwark boundary, so we confirm which council a property falls under before advising.

Typical Herne Hill housing stock

Late-Victorian and Edwardian terraces and semi-detached houses on the streets around Brockwell Park, including the well-known Poets' Corner streets off Railton Road, with mansion flats along the main roads.

Streets we regularly draw for in Herne Hill

Half Moon Lane · Norwood Road · Shakespeare Road · Railton Road

What SE24 is actually built of

Measured from 264 classified residential buildings in SE24, not from a description of the area.

Herne Hill SE24 housing mix

Residential building form across the SE24 postcode district, from 264 classified buildings.

Attached on more than one side56%
Attached on one side35%
Detached8%
Median building footprint74 m²
Addresses per buildingAbove about 2 means flats and maisonettes dominate1.58
Buildings classified264

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 Herne Hill (SE24) 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.

Side return project options
PackageWhat it coversTypical fee
Side return, planning onlyFull householder planning application drawings for the infillFull Planning pack ~£1,600–£2,400
Side return, planning + Building RegulationsAdds structural calculations, Party Wall drawings and construction detailPlanning + Building Regs pack ~£2,200–£3,850
Side return + rear extension (wraparound)Combines both extensions into one L-shaped ground floorsee Wraparound Extension Drawings
Measured survey onlyA measured existing floor-plan set for your own architect, surveyor or builderfrom £450
Sheet from a side return extension drawings package drawn for a Herne Hill property in SE24, showing the existing and proposed arrangement at scale
A sheet from the side return extension drawings package we submit to London Borough of Lambeth for Herne Hill (SE24) properties.

Also in Herne Hill SE24

Planning PermissionPlanning DrawingsArchitectural DrawingsBuilding Regulations DrawingsLoft Conversion DrawingsSide Return Extension Drawings across LambethSide Return Extension Drawings across London
FAQ

Side Return Extension Drawings in Herne Hill SE24 — FAQs

How much does a side return extension cost to design in London?+
Side return drawings start from £1,400. The final fee depends on whether you commission planning drawings alone or a combined planning and building regulations package with structural calculations, all fixed and agreed upfront.
Can I build a side return under permitted development?+
Rarely for a full-width, full-depth side return. Permitted development for side extensions is limited on width and storeys, and most Victorian and Edwardian terraces sit in conservation areas that remove these rights anyway, so a full planning application is the usual route. We still check your specific property first, since some semi-detached and detached houses outside conservation areas retain more generous side-extension allowances.
When do I need to serve Party Wall notice on my neighbour?+
Before work starts, and ideally once your drawings and structural design are settled, since the notice needs accurate dimensions. We can prepare the supporting drawings alongside your planning application so both processes run in parallel.
Do I need an architect for a side return extension?+
No. DrawingsDirect is an MCIAT-chartered architectural technologist practice, so you get the same council-accepted drawings as an architect, for a fixed fee typically around 30% lower, with structural calculations produced in-house.
How long does a side return extension take to design and approve?+
Drawings are typically ready around 7 days from survey. A householder planning application then has a statutory 8-week determination period, running alongside your Party Wall notice period.
Do I need planning permission for a side-return extension in Lambeth?+
On many of Lambeth's Victorian and Edwardian terraces in Brixton, Clapham and Streatham, a single-storey side-return or rear extension can fall within permitted development, so a full application isn't always required. Conservation areas such as Clapham Common and Brixton Water Lane can restrict this. We check your street's designation first and can confirm permitted development with a Lawful Development Certificate.
My Lambeth home is a converted flat — does that change things?+
It often does. Many Lambeth houses are converted flats, so ownership, lease and party-wall considerations can matter as much as the planning route, and the freeholder's agreement is usually needed alongside planning. We resolve the ownership and shared-structure context before drawing so the scheme is deliverable, not just consentable.
What does Lambeth's HMO Article 4 direction affect?+
Lambeth applies an Article 4 direction removing permitted development rights for HMO conversions (C3 to C4) in designated parts of the borough, so a change of use to a house in multiple occupation needs a full application there. It doesn't affect a standard family extension, but we confirm whether it applies to your address and use before advising on a route.
How long does Lambeth Council take to decide?+
Lambeth determines most householder applications within the statutory eight-week period once validated. The terraced grids around Clapham and Brixton are party-wall-sensitive with well-established design expectations, so the commonest delay is a drawing query — we prepare submissions to the borough's residential extension guidance to keep them moving.
How much do planning drawings cost in Lambeth?+
We agree a fixed fee before starting, usually around 30% below an architect's fee for the same council-accepted drawings, with free redraws until Lambeth approves. A side-return, a loft and a flat-conversion scheme differ in complexity, so we quote once we understand your street and project rather than charging by the hour.
Free Fixed Quote

Get your free Herne Hill planning assessment

Tell us your Herne Hill (SE24) address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.