House Extension Drawings in Willesden NW10
Fixed-fee, MCIAT-chartered house extension drawings for Willesden (NW10) homeowners — London Borough of Brent validation and local constraints handled from the start.
Willesden (NW10) in Brent is a densely built late-Victorian and Edwardian neighbourhood centred on Willesden High Road and Walm Lane, where rear and loft projects on the terraces and bay-fronted houses are the everyday work. The Willesden Green conservation area — extended in 2024 — now reaches beyond the High Road parades to take in Brondesbury Park, Rutland Park Mansions and the Chatsworth Road and Dean Road streets.
Two conservation areas shape the district: Willesden Green in the centre and Kensal Rise to the south around Chamberlayne Road. Brent also runs an Article 4 direction on converting houses to small HMOs, so we confirm whether a Willesden address sits inside a conservation-area boundary — and whether a scheme is a householder extension or a change of use — before recommending a permitted-development or full-application route.
Planning in Willesden (NW10): what to know before you apply
Willesden houses generally retain permitted development rights for rear and loft work, but the Willesden Green and Kensal Rise conservation areas control frontages and rooflines across much of NW10, and Brent's Article 4 direction removes the right to convert a house to a small HMO without permission. We check the conservation-area boundary and the proposed use first, then draw to Brent's residential extensions guidance.
Typical Willesden housing stock
Late-Victorian and Edwardian terraces and bay-fronted houses on the streets around Willesden High Road and Walm Lane, with mansion blocks along the main roads and pockets of interwar and post-war infill toward Harlesden and Kensal.
Streets we regularly draw for in Willesden
Willesden High Road · Walm Lane · Chatsworth Road · Dean Road
What NW10 is actually built of
Measured from 424 classified residential buildings in NW10, not from a description of the area.
Willesden NW10 housing mix
Residential building form across the NW10 postcode district, from 424 classified buildings.
| Attached on more than one side | 63% |
|---|---|
| Attached on one side | 33% |
| Detached | 4% |
| Median building footprint | 68 m² |
| Addresses per buildingAbove about 2 means flats and maisonettes dominate | 1.8 |
| Buildings classified | 424 |
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.
House Extension Drawings for Willesden (NW10) homes: the package and the process
Extension drawings are read for their dimensions. The proposed plan needs depth measured from the original rear wall — not from a previous extension — eaves and ridge heights taken from existing ground level, and the distance to each boundary marked. A site plan showing how much garden remains is what an officer reaches for when the amenity question comes up.
We draw the existing building accurately first, because everything else is measured from it. Where the original footprint has already been added to, that history goes on the drawing: it decides which allowances are still available and it is the first thing an officer checks against the council's own records.
The plot decides the extension type long before taste does. A mid-terrace has depth to work with and an alley if it is lucky; a semi has one clear flank; a detached house can go wide. Reading the building form first is what stops a design being drawn that the plot cannot take.
Which extension types do you draw?
Every London extension is shaped by the plot, the neighbours and the borough's design guidance. We draw them all.
Rear extension
A single-storey rear extension is often permitted development within depth limits — ideal for an open-plan kitchen-diner.
Side-return
Fills the alley beside a Victorian terrace, widening the ground floor without losing garden.
Wraparound
Combines a rear and side-return extension for a transformative ground floor, usually needing planning permission.
Double-storey
Adds space above and below, subject to tighter scale and neighbour-impact scrutiny.
Basement
Creates space downward where footprint is limited, with structural and party-wall care.
Do I need planning permission for a house extension in London?
Single-storey rear extensions within permitted development limits (up to 6m for terraced/semi-detached homes under the larger-home scheme, subject to neighbour consultation) may not need a full application. Wraparounds, double-storeys and anything in a conservation area usually do. We assess your plot and recommend the right route before drawing. The current depth, height and eaves limits are set out in full in the guide to planning permission for a rear extension, and where you would rather one practice ran the design, the application and the building-regulations stage together, Architectural Drawings covers that full scope.
How do you maximise the footprint the council will approve?
We know each borough's depth, height and daylight standards, so we design to the edge of what will be approved rather than guessing — and we check the 45-degree neighbour daylight rule and any rear building line before submission. Where a plot is tight we test a permitted-development scheme against a slightly larger householder application and show you the trade-off in space, cost and timescale, so the drawn scheme is the one that actually maximises value rather than just floor area.
| Extension | Typical route | Package | Fee from |
|---|---|---|---|
| Single-storey rear | Permitted development / householder | Planning + building regs | £1,100 |
| Side-return | Householder planning | Planning + building regs + structural | £1,600 |
| Wraparound | Householder planning | Full package + structural | £2,200 |
| Double-storey | Householder planning | Full package + structural | £2,400 |
House Extension Drawings in Willesden NW10 — FAQs
How far can I extend without planning permission in London?+
Do extension drawings include structural calculations?+
How long do extension drawings take?+
Will my rear extension need a party wall agreement?+
Can I extend a house in a conservation area?+
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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