
Planning Drawings in Harrow Weald HA3
Fixed-fee, MCIAT-chartered planning drawings for Harrow Weald (HA3) homeowners — London Borough of Harrow validation and local constraints handled from the start.
Harrow Weald (HA3) runs from the suburban streets off Uxbridge Road up to the wooded Green Belt slopes and Harrow Weald Common on the borough's northern edge. Most householder work is on the inter-war stock — rear and side extensions and loft conversions — but the rural fringe carries much tighter controls.
Three genuine conservation areas sit here: West Drive and Bellfield Avenue (re-designated 2023), the Brookshill Drive and Grimsdyke Estate around Old Redding, and Harrow Weald Park. The Grimsdyke Estate area additionally carries an Article 4 Direction, so we check both the conservation and Green Belt boundaries before advising a route.


Planning in Harrow Weald (HA3): what to know before you apply
Suburban HA3 houses off Uxbridge Road generally keep permitted-development rights for rear and loft projects, but the Brookshill Drive and Grimsdyke Estate conservation area is under an Article 4 Direction, and Green Belt designation on the northern slopes sharply limits new floorspace. Extension design in the West Drive and Bellfield Avenue area must respect its inter-war Domestic Revival character.
Typical Harrow Weald housing stock
Two-storey inter-war Domestic Revival houses on the tree-lined West Drive and Bellfield Avenue, alongside larger detached homes and former estate buildings on the Green Belt slopes around Brookshill and Old Redding.
Streets we regularly draw for in Harrow Weald
West Drive · Bellfield Avenue · Brookshill · Old Redding · Uxbridge Road
What HA3 is actually built of
Measured from 245 classified residential buildings in HA3, not from a description of the area.
Harrow Weald 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 Drawings for Harrow Weald (HA3) homes: the package and the process
A planning set is judged as a set, not as individual sheets. Every existing drawing needs its proposed counterpart at the same scale and orientation so the officer can read the change at a glance, each sheet needs its own number, title, scale bar and north point, and the whole package needs to survive being printed at A3 without a dimension becoming illegible.
We draw to the conventions validation teams expect: plans and elevations at 1:100 or 1:50, a location plan at 1:1250 with the site edged red, a block plan at 1:500, and sections cut where the change in level or roof form actually happens rather than where they are easiest to draw.
The drawing list itself changes with the building. A detached house needs four elevations; a mid-terrace needs two plus a section through the party walls to show what is not visible from outside. Getting that list right at the start is what stops a validation officer asking for a sheet three weeks in.
What is included in a planning drawing set?
A council will only validate an application that contains the right drawings at the right scale. Our standard planning set covers everything a London validation team expects.
- Site location plan (1:1250) and block plan (1:500)
- Existing floor plans, elevations and sections
- Proposed floor plans, elevations and sections
- Roof plans where relevant, with heights and materials annotated
- A design and access or heritage statement where the borough requires one
How are planning drawings different from building regulations drawings?
Planning drawings show what the building will look like and how it sits in its context. Building regulations drawings show how it will be built safely — structure, insulation, fire escape and drainage. Most projects need both; our Complete package covers the two together with structural calculations coordinated in-house.
How quickly can you produce planning drawings in London?
After a laser survey, a standard householder set is typically ready within 7 days. We review every drawing against your borough's validation checklist before it reaches a planner's desk, which is why our first-time approval rate sits around 96%.
| Drawing | Typical scale | What it shows |
|---|---|---|
| Site location plan | 1:1250 | The property in its street context, site edged red |
| Block plan | 1:500 | The building's footprint and position in the plot |
| Floor plans (existing & proposed) | 1:100 / 1:50 | Room layout, walls, openings and the proposed changes |
| Elevations (existing & proposed) | 1:100 / 1:50 | Each face of the building and how it changes |
| Sections | 1:100 / 1:50 | A cut through showing heights, levels and roof form |

Planning Drawings in Harrow Weald HA3 — FAQs
What scale should London planning drawings be?+
Do I need an architect to produce planning drawings?+
How many revisions are included in the fee?+
Can you draw from my existing plans?+
Do planning drawings guarantee approval?+
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?+
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