
HMO Conversion Drawings in Kenton HA3
Fixed-fee, MCIAT-chartered hmo conversion drawings 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.
HMO Conversion Drawings for Kenton (HA3) homes: the package and the process
An HMO scheme is drawn against a schedule. Every bedroom is dimensioned with its usable floor area stated, shared kitchen and bathroom provision is counted against the number of occupants, and the layout has to hold up against the space standards the licensing team applies.
The fire strategy is drawn, not described: protected escape route, fire doors and their ratings, alarm coverage by room, and compartmentation between floors. Licensing and building control assess the same drawing set from different angles, so it has to satisfy both without contradiction.
Room count is a function of the existing plan. A large semi or detached house with generous rooms can meet the space standards without subdivision, while a narrow terrace usually cannot reach the same occupancy without creating rooms that fall below the minimum floor area.
C4 small HMO or sui generis large HMO — which applies to your property?
The distinction matters because it decides which rules apply. A small HMO housing three to six unrelated sharers who share amenities is Class C4. A large HMO of seven or more occupants is sui generis and always needs planning permission, since sui generis uses sit outside the permitted development system entirely. The line also shifts with occupancy — a property let to six sharers today can tip into sui generis territory the moment a seventh tenancy is signed, which changes the planning position even though nothing about the building itself has changed. We assess your proposed occupancy and layout against both definitions before drawing, so the application matches how the property will actually be let.
Do I need planning permission for an HMO conversion in London?
Converting a family home (C3) into a small HMO (C4) is technically permitted development under national rules, but a large number of London boroughs have made an Article 4 direction that removes this right across all or part of the borough — meaning a full planning application is required even for a small, compliant HMO. Article 4 directions vary street by street in some boroughs, so two similar houses a few doors apart can sit on opposite sides of the line. Any large HMO (sui generis) needs planning permission everywhere, regardless of Article 4. We check your specific address against the relevant borough's Article 4 direction before recommending a route, since guessing wrong wastes both time and application fees.
Mandatory and additional HMO licensing — what's required?
Most HMOs need a licence from the council, separate from any planning permission. A licence application typically has to demonstrate that the property meets fire safety, amenity and space standards, that gas and electrical installations are safety-certified, and that the landlord or managing agent is a fit and proper person to hold it.
Mandatory licensing
Applies to any HMO of five or more occupants forming two or more households, regardless of the number of storeys — a national requirement in every London borough.
Additional licensing
Many boroughs extend licensing to smaller HMOs, typically three or four occupants, across all or part of their area. We check the current scheme for your borough before you apply, since schemes and boundaries change.
| Factor | C4 small HMO (3–6 sharers) | Sui generis large HMO (7+) |
|---|---|---|
| Use class | C4 | Sui generis |
| Planning permission | Often needed due to Article 4 directions in most boroughs | Always needed |
| Licensing | Mandatory if 5+ occupants; additional licensing in many boroughs | Mandatory |
| Typical drawing package | From £1,400 | Full planning + building regs, from £2,200 |

HMO Conversion Drawings in Kenton HA3 — FAQs
How much do HMO conversion drawings cost in London?+
Is HMO conversion permitted development in London?+
Do I need a licence as well as planning permission?+
Do I need an architect for an HMO conversion?+
How long do HMO conversion drawings take?+
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?+
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