Dormer loft bedroom in a London home, a popular Harrow interwar-semi conversion

Harrow · London

Planning Drawings in Harrow

Name: Householder planning decisions, Harrow
Creator: Ministry of Housing, Communities and Local Government (PS2 district planning application statistics)
License: https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/

Fixed-fee, MCIAT-chartered planning drawings for Harrow homeowners — London Borough of Harrow validation and local constraints handled from the start.

Harrow is Metro-land in built form: rows of interwar semi-detached and detached houses across Rayners Lane, Kenton, Stanmore and Wealdstone that lend themselves to hip-to-gable and dormer loft conversions and rear extensions. On these homes such work frequently qualifies as permitted development within the volume limits, so a full application is not always needed. The London Borough of Harrow pays close attention to preserving the rhythm and consistent 1930s building line of these suburban streets, and expects extensions to respect the established line and roof form of the neighbouring houses.

The picture changes in the borough's heritage cores. Harrow on the Hill carries a protected heritage setting and long views, and Pinner's medieval high street and Pinner Hill, along with Roxeth and Harrow Weald, are conservation areas where permitted development is often restricted and a full, context-led application is required. Harrow also applies Article 4 directions to HMO conversions in designated wards and to front-boundary and hardstanding works in some areas, so the right route depends on your exact address rather than the house type alone.

We prepare Harrow planning drawings that respect the building line and roof form the borough expects, checking permitted development eligibility for semi-detached and detached homes first and confirming it with a Lawful Development Certificate where the work qualifies. In the conservation areas we design to the character of the area — materials, proportions and rooflines — and evidence the heritage considerations so the submission stands up. The fee is fixed and agreed up front, usually around 30% below an architect's charge for the same council-accepted drawings, with free redraws until Harrow approves. Drawing to the council's validation checklist, and turning drawings around in roughly seven days, keeps most applications inside the statutory eight-week determination without a validation query.

Proposed floor plan

Harrow

Planning in Harrow: what to know before you apply

Harrow applies Article 4 directions to HMO conversions in designated wards and controls development within Harrow on the Hill and Pinner conservation areas. For the borough's abundant 1930s semis, hip-to-gable lofts and rear extensions frequently qualify as permitted development.

Typical Harrow housing stock

Classic Metro-land interwar semi-detached and detached houses, with the historic hilltop core of Harrow on the Hill and Pinner's medieval high street.

Areas we regularly draw for in Harrow

Harrow · Pinner · Stanmore · Wealdstone · Rayners Lane · Kenton · Hatch End

What the numbers say about Harrow planning decisions

These are London Borough of Harrow’s own reported figures, published by government rather than estimated by us. They are what we design against — a borough that refuses one householder application in five needs a different drawing package from one that refuses one in twenty.

Householder decisions in Harrow

Every householder application London Borough of Harrow decided over the four quarters to 2026 Q1.

Householder applications decided	894
Granted	739
Refused	155
GrantedEngland average 90%	83%
Of which prior approvalsPrior approvals are granted far more often than full applications, so this share moves the rate above	24%
Decided within 8 weeksExcludes prior approvals. England average 93%	94%

Source: Ministry of Housing, Communities and Local Government (PS2 district planning application statistics). Open Government Licence v3.0 Extracted 2026-08-16.

Permitted development in Harrow

Larger householder extensions put to London Borough of Harrow under the prior-approval route, and lawful-development certificates decided, over eight quarters.

Prior approval not requiredWent ahead without a full application	617
Prior approval granted	47
Prior approval refused	171
Granted where a decision was neededFrom 218 determinations	22%
Building upwards, prior approval refused	0
Certificates of lawful development decided	584

Source: Ministry of Housing, Communities and Local Government (PS1 district planning application statistics). Open Government Licence v3.0 Extracted 2026-08-16.

Designated areas in Harrow

Conservation areas London Borough of Harrow has published to the national register, and when it designated them. Where a borough has supplied no Article 4 data the row is omitted rather than shown as zero.

Conservation areas on the register	27

Source: MHCLG Planning Data Platform. Open Government Licence v3.0 Extracted 2026-08-16.

If London Borough of Harrow refuses: appeal outcomes

Planning appeals against London Borough of Harrow determined by the Planning Inspectorate, 2021–2026. Enforcement notices and withdrawn cases are excluded.

Appeals determined	609
Allowed	214
Dismissed	395
Householder appeals allowedFrom 319 householder appeals. England average 36%	42%

Source: Planning Inspectorate appeals casework. Open Government Licence v3.0 Extracted 2026-08-16.

Planning Drawings for Harrow 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%.

What a London planning drawing set contains
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

Sheet from a planning drawings package prepared for a Harrow property, drawn to London Borough of Harrow validation standards — A sheet from the planning drawings package we submit to London Borough of Harrow.

Local Areas

Planning Drawings across Harrow

Also in Harrow

Planning Permission Architectural Drawings Building Regulations Drawings Loft Conversion Drawings House Extension Drawings Planning Drawings across London

FAQ

Planning Drawings in Harrow — FAQs

What scale should London planning drawings be?+

Site location plans are 1:1250, block plans 1:500, and floor plans, elevations and sections are typically 1:100 or 1:50. We format every drawing to your specific borough's requirements.

Do I need an architect to produce planning drawings?+

No. MCIAT-chartered architectural technologists produce the same council-accepted planning drawings with the same professional accountability, and councils assess the drawings, not the author's job title.

How many revisions are included in the fee?+

All of them. The fee is fixed and we redraw free until your council approves — revisions requested by a planning officer never cost you extra.

Can you draw from my existing plans?+

We can work from existing measured drawings, but for accuracy we usually carry out a laser survey so the proposed set matches your property exactly.

Do planning drawings guarantee approval?+

No drawing can guarantee a decision, but drawing to the local plan and validation checklist maximises your odds — and we redraw free until approval.

Do I need planning permission for a loft conversion in Harrow?+

Harrow's Metro-land semis and detached houses in Rayners Lane, Kenton and Stanmore suit hip-to-gable and dormer lofts, which frequently qualify as permitted development within the volume limits. The exceptions are the conservation areas — Harrow on the Hill and Pinner's historic core — and the Article 4 wards. We check your address and can confirm permitted development with a Lawful Development Certificate.

What does Harrow expect for a rear extension on a 1930s semi?+

The council pays close attention to preserving the rhythm and building line of its interwar suburban streets, so extensions are expected to respect the established line and roof form. Many single-storey rear extensions still fall within permitted development; where a full application is needed, we design to the borough's residential guidance so it validates and approves without repeated revisions.

Can I extend a home in Harrow on the Hill or Pinner?+

Yes, but these historic conservation areas carry a heritage setting and long views the council protects closely, so permitted development is often restricted and a full, context-led application is required. We design to the character of the area — materials, proportions and rooflines — and evidence the heritage considerations so the submission stands up.

How long does Harrow Council take to decide?+

Harrow determines most householder applications within the statutory eight-week period once validated. The commonest delay is a validation query, so we prepare Harrow submissions to the council's checklist with correctly scaled existing and proposed drawings and a location plan to keep the application on track.

How much do planning drawings cost in Harrow?+

We work to a fixed fee agreed upfront, usually around 30% below an architect's charge for the same council-accepted drawings, with free redraws until Harrow approves. The figure depends on the scheme — a dormer loft differs from a double-storey extension — so we confirm it once we understand your project rather than billing by the hour.

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