
Rear Extension Drawings in Brent
Fixed-fee, MCIAT-chartered rear extension drawings for Brent homeowners — London Borough of Brent validation and local constraints handled from the start.
Brent runs from the dense Victorian and Edwardian terraces of Kilburn, Willesden and Harlesden, through the planned streets of Queen's Park, to the interwar semi-detached suburbia of Wembley, Kingsbury and Sudbury. Side-return and rear extensions and hip-to-gable loft conversions are the borough's most requested projects, and the housing character shifts noticeably across it — from party-wall-sensitive terraced grids to the consistent interwar semi character the council expects extensions to respect toward Wembley and Kingsbury. Conservation control around Queen's Park, Mapesbury and Sudbury Court, and in Roundwood, Brondesbury and Willesden Green, tightens design where it applies.
For the borough's abundant terraces and interwar semis, single-storey side-returns and hip-to-gable or dormer lofts frequently qualify as permitted development within the volume limits, so a full application isn't always needed. But Brent operates a borough-wide Article 4 direction removing permitted development for change of use to an HMO (C3 to C4), meaning any conversion to a house in multiple occupation needs a full application anywhere in the borough, and conservation areas such as Queen's Park, Mapesbury and Sudbury Court restrict what would otherwise be permitted. We take a validation-first approach, confirming the designation for your street and, where a scheme qualifies, evidencing permitted development with a Lawful Development Certificate before drawing.
We prepare Brent planning and building-regulations drawings to the council's householder and validation standards across Wembley, Willesden, Kilburn, Harlesden, Neasden and Sudbury, producing the same council-accepted drawings an architect would — usually at around 30% less. The fee is fixed and agreed before we start, drawings typically turn around in about seven days, and we redraw free until Brent approves. Most householder applications are determined within the statutory eight-week period once validated, and because the dense terraced streets are party-wall-sensitive the commonest delay is a drawing query, so a complete submission to the council's householder guidance keeps the application moving.


Planning in Brent: what to know before you apply
Brent operates a borough-wide Article 4 direction removing permitted development rights for HMO conversions, and controls design within conservation areas such as Queen's Park, Mapesbury and Sudbury Court. For the borough's abundant terraces and interwar semis, side-returns and hip-to-gable lofts frequently qualify as permitted development — we confirm the designation for your street before drawing.
Typical Brent housing stock
Victorian and Edwardian terraces across Kilburn, Willesden and Harlesden, interwar semi-detached suburbia through Wembley, Kingsbury and Sudbury, and the distinctive planned streets of Queen's Park and the Sudbury Court estate.
Areas we regularly draw for in Brent
Wembley · Willesden · Kilburn · Harlesden · Kingsbury · Neasden · Sudbury · Queen's Park
Rear Extension Drawings for Brent homes: the package and the process
Every rear extension drawings we prepare for a Brent property is drawn to London Borough of Brent’s validation standards and tuned to the local constraints above. Here is what the drawing package covers and how the process runs from first survey to approval.
A single-storey rear extension is the most common way London homeowners add space, usually taking the form of an open-plan kitchen-diner that opens onto the garden through bi-fold or sliding doors, with rooflights or a roof lantern bringing daylight deep into the plan. Because depth and height are tightly controlled by permitted development rules and by the 45-degree rule that protects neighbouring windows, the design work sits as much in checking what the council will allow as in drawing what you want.
DrawingsDirect draws rear extensions for permitted development, the larger home extension prior-approval scheme and full householder planning, with structural calculations for the opening and roof produced in-house by our MCIAT-chartered team. If your project also involves widening the kitchen sideways or adding a second storey, see our Side Return, Wraparound and Double Storey Extension pages — many London rear extensions grow into one of those during design.
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.
| Route | When it applies | Typical fee |
|---|---|---|
| Permitted development (Lawful Development Certificate) | Depth within 3m (terraced/semi) or 4m (detached), height and materials within PD limits | PD/LDC pack ~£950–£1,450 |
| Larger home extension (prior approval) | Depth up to 6m (terraced/semi) or 8m (detached), with neighbour notification | from £1,100 |
| Full householder planning permission | Extension exceeds PD/larger-home limits, or the property is in a conservation area with an Article 4 direction | Full Planning pack ~£1,600–£2,400 |
| Planning + Building Regulations (structural) | Combined planning and construction-ready pack with structural calculations for the opening and roof | Planning + Building Regs pack ~£2,200–£3,850 |
Rear Extension Drawings across Brent
Rear Extension Drawings in Brent — FAQs
How much does a rear extension cost to design in London?+
Do I need an architect for a rear extension?+
How long does it take to get rear extension drawings?+
What is the 45-degree rule?+
Will I need a Party Wall Agreement for a rear extension?+
Do I need planning permission for a side-return extension in Brent?+
What does Brent's borough-wide HMO Article 4 direction affect?+
Is a hip-to-gable loft conversion allowed on my Brent semi?+
How long does Brent Council take to decide?+
How much do planning drawings cost in Brent?+
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Tell us your Brent address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.