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Free 2026 London Planning ReportRear Extension Drawings in Southall UB2

Kitchen extension interior in a Southall UB2 Edwardian terraced home
Southall · UB2 · Ealing

Rear Extension Drawings in Southall UB2

Fixed-fee, MCIAT-chartered rear extension drawings for Southall (UB2) homeowners — London Borough of Ealing validation and local constraints handled from the start.

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In Southall (UB2) we produce planning and building-regulation drawings for rear extensions, side-return kitchens and loft conversions on the area's Edwardian and interwar homes.

Where a plot sits within or near the Canalside conservation area we check the boundary and the canal-frontage constraints first, then advise whether the work is permitted development or needs a full planning application.

Kitchen extension interior in a Southall UB2 Edwardian terraced home
Isometric illustration of a Southall UB2 home rear extension drawings design
Proposed floor plan
Southall UB2

Planning in Southall (UB2): what to know before you apply

Most UB2 homes away from the canal retain permitted-development rights for rear extensions and lofts. Plots inside the Canalside conservation area face tighter control on anything visible from the towpath, and the Blue Ribbon/SINC designation adds ecology checks near the water.

Typical Southall housing stock

South Southall (UB2) is largely Edwardian and interwar terraces and semis around Norwood Green and Tentelow Lane, with the Grand Union Canal corridor forming the Canalside conservation area along its southern edge.

Streets we regularly draw for in Southall

Norwood Road · Tentelow Lane · Osterley Park Road · Regina Road

What UB2 is actually built of

Measured from 379 classified residential buildings in UB2, not from a description of the area.

Southall UB2 housing mix

Residential building form across the UB2 postcode district, from 379 classified buildings.

Attached on more than one side50%
Attached on one side45%
Detached5%
Median building footprint65 m²
Addresses per buildingAbove about 2 means flats and maisonettes dominate1.27
Buildings classified379

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.

Rear Extension Drawings for Southall (UB2) homes: the package and the process

Depth is the number the application turns on, and it has to be measured from the original rear wall of the house rather than from whatever is there now. The drawings carry that dimension, the eaves and ridge heights, the position of any rooflight, and the boundary distances on both sides.

Where the scheme goes beyond the standard allowance and relies on the larger home extension route, the drawings serve a second purpose: they are what the council sends to the neighbours during the consultation. A clear, dimensioned proposed elevation answers the objection about overshadowing before it is made.

Depth is limited by the plot as much as by the rules. A long garden behind a terrace can take the full allowance, while a short one runs out before the rules do — and on a semi or detached house the same depth reads very differently from the boundary.

Do I need planning permission for a rear extension in London?

Many single-storey rear extensions qualify as permitted development, meaning no planning application is needed, provided depth, height and materials stay within set limits. That changes if your property sits in a conservation area or is subject to an Article 4 direction, both of which can remove permitted development rights across a street or borough — in that case a full householder planning application is required regardless of size.

Even where an extension qualifies, most homeowners obtain a Lawful Development Certificate to confirm that status in writing before building — useful for mortgage lenders, buyers and Building Control. We check your property against your borough's constraints before recommending a route.

How deep can a single-storey rear extension go?

Depth is the main constraint on a rear extension, and it depends on your house type and whether you use standard permitted development or the larger home extension scheme.

Permitted development

Standard permitted development allows a single-storey rear extension up to 3 metres deep for terraced and semi-detached houses, or 4 metres for detached houses, generally with eaves height limited to match or stay close to the existing house.

Larger home extension scheme

The prior-approval scheme extends this to 6 metres for terraced and semi-detached houses and 8 metres for detached houses. Your council writes to affected neighbours; if none object within the notification period, approval follows without a full planning application. If an objection is raised, the council assesses the impact on neighbouring light and outlook itself, rather than automatically refusing, so a well-considered design still has a good chance of approval.

Designing the kitchen-diner: rooflights, bi-folds and daylight

Most rear extensions exist to create one open-plan kitchen, dining and living space, so the drawing work focuses on getting light and flow right within the depth you are allowed.

  • Structural opening sized for bi-fold or sliding doors across most of the rear elevation
  • Rooflights or a roof lantern positioned to light the centre of the room, away from the shadow line of the main house
  • Open-plan layout tested against the 45-degree rule, which protects daylight to your neighbours' windows and can limit how close a flank wall or roof comes to the boundary
  • Floor build-up and threshold detail coordinated so the new floor meets the existing one without a step
Rear extension routes at a glance
RouteWhen it appliesTypical fee
Permitted development (Lawful Development Certificate)Depth within 3m (terraced/semi) or 4m (detached), height and materials within PD limitsPD/LDC pack ~£950–£1,450
Larger home extension (prior approval)Depth up to 6m (terraced/semi) or 8m (detached), with neighbour notificationfrom £1,100
Full householder planning permissionExtension exceeds PD/larger-home limits, or the property is in a conservation area with an Article 4 directionFull Planning pack ~£1,600–£2,400
Planning + Building Regulations (structural)Combined planning and construction-ready pack with structural calculations for the opening and roofPlanning + Building Regs pack ~£2,200–£3,850
Sheet from a rear extension drawings package drawn for a Southall property in UB2, showing the existing and proposed arrangement at scale
A sheet from the rear extension drawings package we submit to London Borough of Ealing for Southall (UB2) properties.
FAQ

Rear Extension Drawings in Southall UB2 — FAQs

How much does a rear extension cost to design in London?+
Rear extension drawings start from £1,100, with the final fee set by the route your extension takes — permitted development, prior approval or full planning — and whether you need building regulations and structural calculations bundled in. The fee is fixed and agreed upfront.
Do I need an architect for a rear extension?+
No. DrawingsDirect is an MCIAT-chartered architectural technologist practice, producing the same council-accepted drawings as an architect for a fixed fee typically around 30% lower.
How long does it take to get rear extension drawings?+
Drawings are typically ready around 7 days from survey. Once submitted, councils have a statutory 8-week period to determine a standard householder planning application.
What is the 45-degree rule?+
It is a daylight test many London councils apply to check that a rear extension does not block too much light to a neighbour's nearest window, measured as a line drawn at 45 degrees from that window. We check it before submission, not after a refusal.
Will I need a Party Wall Agreement for a rear extension?+
Only if your foundations or new walls sit on or near the boundary with a neighbouring property. A straightforward rear extension set within your own plot often does not trigger the Party Wall etc. Act 1996, unlike a Side Return or Wraparound extension, which usually does.
Do I need planning permission for a rear extension in Ealing?+
Many Ealing semis and terraces keep permitted development rights for a single-storey rear extension, so a full application isn't always needed. But the borough-wide Article 4 direction on HMO conversions, and conservation areas such as Bedford Park and Pitshanger, remove or restrict those rights in places. We check your address against the designations first and, where it qualifies, confirm permitted development with a Lawful Development Certificate.
What extra control applies in Bedford Park?+
Bedford Park is one of West London's most tightly controlled conservation areas, with detailed control over materials, rooflines, windows and front elevations. A standard permitted-development dormer or cladding change usually won't apply; instead we design to the area's Arts-and-Crafts character and prepare a full householder application with the elevations and materials the council expects — the reliable route to approval there.
How long does Ealing Council take to decide a householder application?+
Ealing determines most householder applications within the statutory eight-week period once they are validated. The commonest cause of delay is a validation query over missing or inconsistent drawings, so we prepare Ealing submissions to the council's validation checklist — correctly scaled existing and proposed plans, elevations and a location plan — to avoid that back-and-forth.
Can you help with a loft conversion on a 1930s Ealing semi?+
Yes. Ealing's Metro-land semis in Perivale, Greenford and Northolt suit hip-to-gable and dormer loft conversions, which frequently qualify as permitted development on semi-detached homes within the volume limits. We confirm eligibility against those limits and any Article 4 or conservation constraint, then produce the planning and building-regulations drawings.
How much do planning drawings cost in Ealing?+
We work to a fixed fee agreed before we start, typically around 30% below an architect's charge for the same council-accepted drawings, with free redraws until Ealing grants approval. The exact figure depends on the project — a single-storey rear extension differs from a double-storey or a loft — so we quote once we understand your scheme rather than on an open-ended hourly basis.
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