
Planning Permission in Kenton HA3
Fixed-fee, MCIAT-chartered planning permission for Kenton (HA3) homeowners — London Borough of Harrow validation and local constraints handled from the start.
Kenton (HA3) is a 1930s semi-detached suburb straddling the Harrow–Brent border, where the everyday project is a rear kitchen extension, a hip-to-gable or L-shaped dormer loft, or a two-storey side extension that adds a bedroom while keeping the interwar frontage in proportion.
Around the Mount Stewart and Northwick Circle conservation areas we take extra care with roof form, materials and the building line, and we always confirm whether an address falls to Harrow Council so the application is validated first time.


Planning in Kenton (HA3): what to know before you apply
No published householder Article 4 direction, though the Mount Stewart and Northwick Circle conservation areas curb some permitted-development rights; the main watch-points are matching the semi-detached roofline and confirming the correct authority near the Harrow/Brent boundary.
Typical Kenton housing stock
Interwar semi-detached and short terraced houses laid out as a 1930s suburb straddling the Harrow and Brent border, typically with bay windows, hipped roofs and off-street parking. Plots are regular with modest-to-generous rear gardens well suited to single-storey additions.
Streets we regularly draw for in Kenton
The Ridgeway · Draycott Avenue · Windermere Avenue · Northwick Circle
What HA3 is actually built of
Measured from 245 classified residential buildings in HA3, not from a description of the area.
Kenton HA3 housing mix
Residential building form across the HA3 postcode district, from 245 classified buildings.
| Attached on more than one side | 41% |
|---|---|
| Attached on one side | 51% |
| Detached | 9% |
| Median building footprint | 72 m² |
| Addresses per buildingAbove about 2 means flats and maisonettes dominate | 1.18 |
| Buildings classified | 245 |
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.
Planning Permission for Kenton (HA3) homes: the package and the process
A householder application is refused validation far more often than it is refused permission, and almost always for the same reasons: a location plan at the wrong scale, no red line around the application site, a missing ownership certificate, or elevations that do not show every face of the building affected. We prepare the full submission set — location plan, block plan, existing and proposed floor plans, elevations and sections — so the case officer receives a complete case on day one.
Once the application is live we stay on it. Officers routinely come back with questions about materials, boundary treatment or a dimension they cannot read off the drawings, and a fast, drawn answer is usually the difference between a decision inside the statutory period and a request to withdraw and resubmit.
Which route applies is decided by the building before it is decided by policy. A house that has never been extended usually has allowances left to use; a flat, a listed building or a home in a conservation area often has none, and the same drawing set then has to make a design case rather than a compliance one.
Do I need planning permission for an extension in London?
Many single-storey rear extensions, loft conversions and outbuildings fall under permitted development rights and do not need a full planning application — but London's dense housing stock, conservation areas and Article 4 directions frequently withdraw those rights. Before you pay for a full application, we check your property against the current permitted development thresholds and your borough's local constraints.
Where permitted development applies, we recommend a Lawful Development Certificate instead of full planning — it is faster, cheaper and gives you a legal document confirming the work was lawful. Where a full application is genuinely required, we prepare it properly the first time.
Permitted development vs a full planning application
Permitted development lets you build within defined volumetric limits without committee review. A full householder application is assessed against the borough's local plan for scale, daylight, neighbour impact and design. We advise which route your project qualifies for and why.
Article 4 directions and conservation areas
If your home sits in a conservation area or under an Article 4 direction, permitted development rights are often removed — meaning even modest changes need consent. Each borough page lists the local directions and conservation areas we routinely design around.
How do you apply for planning permission through the London Planning Portal?
We manage the full lifecycle of your submission — survey, drawings, supporting documents and officer liaison — so you never have to decode a validation checklist yourself.
Phase 1 — existing and proposed site surveys
A laser-measured survey captures your property exactly, so existing and proposed drawings match reality millimetre for millimetre.
Phase 2 — technical drawing package
Site location plan, block plan, floor plans, elevations and sections drawn to your borough's scale and formatting requirements, with a design and access statement where needed.
Phase 3 — liaison with the planning officer
We answer the council's queries, negotiate amendments, and redraw free until the decision lands.
How long does planning permission take, and what does it cost?
Drawings are typically ready within 7 days of survey. Your council then has a statutory 8 weeks to decide a householder application. Our drawing fees are fixed and quoted upfront — the table below shows typical packages.
| Package | Production window | Compliance layer | Typical fee |
|---|---|---|---|
| Permitted Development pack | 7–10 working days | Lawful Development Certificate submission | £950–£1,450 |
| Full Planning pack | 10–14 working days | Council liaison & design statement | £1,600–£2,400 |
| Planning + Building Regs pack | 14–21 working days | Structural calculations included | £2,200–£3,850 |

Planning Permission in Kenton HA3 — FAQs
How long does it take to get planning permission from a London council?+
What happens if the council refuses?+
Do you cover my borough?+
Is the fee really fixed?+
Do I need planning permission for a loft conversion in Harrow?+
What does Harrow expect for a rear extension on a 1930s semi?+
Can I extend a home in Harrow on the Hill or Pinner?+
How long does Harrow Council take to decide?+
How much do planning drawings cost in Harrow?+
Get your free Kenton planning assessment
Tell us your Kenton (HA3) address and ambition — we'll confirm feasibility, local constraints and a fixed fee within one working day.