Kitchen extension interior in a Hendon NW4 family home, Barnet

Hendon · NW4 · Barnet

Side Return Extension Drawings in Hendon NW4

Fixed-fee, MCIAT-chartered side return extension drawings for Hendon (NW4) homeowners — London Borough of Barnet validation and local constraints handled from the start.

Hendon (NW4) in Barnet ranges from the historic Church End village around St Mary's church to streets of Victorian and interwar houses, and the usual brief is a rear or side extension or a loft conversion to add family space.

The Hendon Church End conservation area protects the medieval church core, its listed buildings and the hilltop views, so if your home sits inside the boundary we check it first and steer massing and materials before deciding between permitted development and a full householder application.

Proposed floor plan

Hendon NW4

Hendon (NW4) — planning at a glance

Council: London Borough of Barnet
Postcode district: NW4
Planning portal: View the Barnet planning portal
Housing stock: A linear historic village around the medieval St Mary's parish church, where over half the buildings are residential, set among Victorian and interwar houses that make up the wider NW4 suburb.
Article 4: No Article 4 direction is confirmed for the Hendon Church End conservation area, so permitted-development rights are not withdrawn — but the designation still controls changes around the historic St Mary's church core and its listed buildings.
Conservation: Hendon Church End Conservation Area
Sample streets: Church Road · Church End · Greyhound Hill · Parson Street
Local constraints: Hendon Church End conservation area (designated 1983) centres on the 13th-century St Mary's church and hilltop views, so additions must protect the low-rise historic settingSeveral buildings in the area are listed or held by neighbouring Middlesex University, tightening control over adjacent worksThe elevated Church End ridge affords long views across the borough, so roof additions are assessed for their impact on the skyline

Planning in Hendon (NW4): what to know before you apply

Across the wider NW4 suburb, rear extensions and loft conversions typically proceed under permitted development or a lawful-development certificate. Inside the Church End conservation area, or near the listed buildings around St Mary's, expect a full householder application with attention to setting and skyline.

Typical Hendon housing stock

A linear historic village around the medieval St Mary's parish church, where over half the buildings are residential, set among Victorian and interwar houses that make up the wider NW4 suburb.

Streets we regularly draw for in Hendon

Church Road · Church End · Greyhound Hill · Parson Street

What NW4 is actually built of

Measured from 377 classified residential buildings in NW4, not from a description of the area.

Hendon NW4 housing mix

Residential building form across the NW4 postcode district, from 377 classified buildings.

Attached on more than one side	30%
Attached on one side	53%
Detached	18%
Median building footprint	83 m²
Addresses per buildingAbove about 2 means flats and maisonettes dominate	2.03
Buildings classified	377

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 Hendon (NW4) 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
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

Sheet from a side return extension drawings package drawn for a Hendon property in NW4, showing the existing and proposed arrangement at scale — A sheet from the side return extension drawings package we submit to London Borough of Barnet for Hendon (NW4) properties.

Also in Hendon NW4

Planning Permission Planning Drawings Architectural Drawings Building Regulations Drawings Loft Conversion Drawings Side Return Extension Drawings across Barnet Side Return Extension Drawings across London

FAQ

Side Return Extension Drawings in Hendon NW4 — 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 loft or extension in Barnet?+

Across Finchley, Edgware and Hendon, Barnet's 1930s semis usually keep permitted development rights for rear extensions and hip-to-gable or dormer lofts, so a full application isn't always needed. The major exception is Hampstead Garden Suburb, where an Article 4 direction removes almost all permitted development rights. We check your address first and confirm permitted development with a Lawful Development Certificate where it applies.

What is different about building in Hampstead Garden Suburb?+

The Suburb has one of the most far-reaching Article 4 directions in London: almost all external alterations need planning permission, and the Hampstead Garden Suburb Trust must also consent to changes in parallel with the council. We handle both tracks — a carefully evidenced planning application to Barnet and the Trust's design requirements — since approval there depends on respecting the Arts-and-Crafts character precisely.

Is a hip-to-gable loft conversion allowed on my Barnet semi?+

Usually, yes. The borough's abundant interwar semis are well suited to hip-to-gable and dormer conversions, which frequently qualify as permitted development on semi-detached homes within the volume limits. Outside conservation areas and the Suburb, this is often the quickest route. We confirm eligibility, then produce the planning and building-regulations drawings.

How long does Barnet take to decide an application?+

Barnet determines most householder applications within the statutory eight-week period once validated; Suburb and conservation cases can involve additional consultation. We prepare Barnet submissions to the validation checklist, with the elevations and materials detail the council expects, to avoid the drawing queries that are the usual cause of delay.

How much do Barnet planning drawings cost?+

We agree a fixed fee before we start, typically around 30% below an architect's fee for the same council-accepted drawings, with free redraws until Barnet approves. A straightforward Finchley loft and a Hampstead Garden Suburb application differ in the evidence required, so we quote once we have seen the project and know which route applies.

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