Harrow planning permission: 1 in 8 goes to committee

Why does Harrow send so much to committee?

Harrow delegated 87.3% of its planning decisions to case officers, the lowest rate of the 33 boroughs against a London figure of 97.0%. Roughly one decision in eight goes before councillors, which adds weeks. Harrow approved 77.8% of 2,856 householder applications.

Source: MHCLG District Planning Application Statistics (PS1 and PS2), decisions made in the twelve quarters to March 2026, and Planning Inspectorate casework decided 2016–2026. Open Government Licence v3.0, retrieved 1 September 2026. Harrow is the one London borough whose return carries a suspected reporting spike, on its listed-building works certificates; no figure from that field is quoted here.

Planning in Harrow — what you need to know

Harrow sends more of its planning applications to committee than any other London borough. It delegated 87.3% of decisions to officers (MHCLG planning statistics, retrieved 1 September 2026) — the lowest share in London, where most councils are above 97%. Roughly one decision in eight is therefore taken in public by elected members rather than by a case officer, and that changes the calculation: local objection carries more weight here than the policy documents alone would suggest.

Outer north-west London suburban; Harrow on the Hill has exceptionally strict heritage controls; rest of borough permissive. The borough has a population of approximately 261,000 residents and covers postcodes HA1, HA2, HA3, HA5, HA7, HA8.

The housing stock in Harrow is predominantly 1930s semi-detached dominates; Edwardian villas in Harrow on the Hill and Pinner; Metropolitan Green Belt in Stanmore and Harrow Weald; post-war flats around Harrow Central. This mix of property types means that Harrow Council deals with a wide range of applications, from rear extensions on terraced houses to loft conversions on semi-detached properties and full refurbishments of period homes in conservation areas.

With 29 designated conservation areas and no current Article 4 Directions,Harrow granted 869 prior approvals for larger rear extensions, the highest count of any borough in this guide (MHCLG planning statistics, retrieved 1 September 2026). It also refused 634 householder applications outright, at a 77.8% approval rate. Both belong to the same borough because Harrow is really two: the interwar semis of Rayners Lane, Kenton and Wealdstone, where deep rear gardens make the larger-extension route straightforward, and Harrow on the Hill and Pinner Village, where heritage control is as tight as anywhere in outer London.

At Architectural Drawings London, we prepare planning drawings and building regulations drawings for properties across all Harrow postcodes. Our MCIAT chartered architectural technologists have experience with Harrow Council and understand the specific policies, design guides, and precedents that apply in Harrow.

Are there Article 4 Directions in Harrow?

Harrow does not currently have any borough-wide Article 4 Directions that restrict Permitted Development rights for standard householder developments such as loft conversions, rear extensions, or outbuildings.

This means that most common home improvements in Harrow can proceed under Permitted Development without needing to apply for planning permission, provided they meet the national criteria for size, height, and position. We recommend applying for a Lawful Development Certificate (£274) to formally confirm that your project qualifies as Permitted Development. This provides legal certainty and is valuable when selling the property.

Even without Article 4 Directions, properties in Harrow's 29 conservation areas have additional restrictions on permitted development. We check the specific restrictions affecting your property as part of our initial assessment.

How many conservation areas does Harrow have?

Harrow has 29 designated conservation areas. Notable conservation areas include:

• Harrow on the Hill
• Pinner Village
• Stanmore
• Harrow Weald

In conservation areas, Permitted Development rights are more restricted than in non-designated areas. Key restrictions include:

• No cladding, stone, artificial stone, pebble dash, render, timber, plastic, or tile to any external wall without planning permission
• No side extensions under Permitted Development
• Rear extensions are limited and may require planning permission
• Dormer loft conversions facing the highway require planning permission
• Satellite dishes on front elevations or chimneys are not permitted
• Demolition of gates, walls, fences, or other boundary treatment requires planning permission

Twenty-nine conservation areas without a borough-wide Article 4 Direction, and Harrow on the Hill applying heritage controls stricter than anything else in the borough. Because so much reaches committee, a conservation-area application in Harrow is one where the presentation drawings genuinely matter — they will be looked at by members, not only by an officer who reads appraisals for a living. We prepare accordingly.

Popular projects in Harrow

Interwar semis across most of the borough, Edwardian villas at Harrow on the Hill and Pinner, Green Belt at Stanmore and Harrow Weald, and post-war flats near the town centre. Harrow took 4,137 planning decisions in three years and approved 73.6%, with new-dwelling schemes at 46.5% (MHCLG planning statistics, retrieved 1 September 2026). Given the committee route above, a conversion proposal here should be planned on the assumption that neighbours will be heard.

Two-storey extensions

The semi-detached and detached housing stock in Harrow is well suited to two-storey rear extensions, which almost always require planning permission. A two-storey extension can add a larger kitchen-diner at ground floor and an additional bedroom and bathroom above. Harrow Council generally supports two-storey extensions that are subordinate to the original dwelling, set in from the boundary, and do not result in unacceptable loss of light or privacy to neighbours.

Flat conversions and internal alterations

With mansion blocks and converted flats forming part of Harrow's housing stock, internal layout changes and flat conversions are common projects. While internal alterations rarely need planning permission, converting a house to flats (C3 to C4 HMO) or vice versa may require planning approval. We can prepare the necessary floor plans, elevations, and supporting documents for flat conversion applications in Harrow.

How much do planning drawings cost in Harrow?

The council charge is nationally set. The Harrow-specific cost is the possibility of a committee date, which adds weeks that no statutory target accounts for, and 1,313 applications had an extension of time agreed — 31.7% of decisions (MHCLG planning statistics, retrieved 1 September 2026). Budget calendar rather than fee. Our drawing package is quoted as one fixed figure before the survey, roughly 30% under the London architect rate.

We include a measured survey, existing and proposed plans, elevations, and a site plan — everything required for a valid planning submission to Harrow Council. Our fees are 30% below typical London architect rates for the same scope of work.

In a borough where more decisions than usual are made in public, the attraction of the proposed certificate is that it is decided by an officer on the facts rather than by members on the merits - it takes the project out of that process entirely. Harrow granted 1,147 of them over three years (MHCLG planning statistics, retrieved 1 September 2026).

Our experience in Harrow

We cover all Harrow postcodes: HA1, HA2, HA3, HA5, HA7, HA8. Whether your property is in a conservation area, affected by an Article 4 Direction, or in an unrestricted residential street, we have experience with Harrow Council and understand the borough's planning policies.

Our MCIAT chartered architectural technologists prepare planning drawings and building regulations drawings for residential projects across Harrow. We handle the full process from initial measured survey through to planning submission, and we liaise with Harrow Council on your behalf.

We also work in Harrow's neighbouring boroughs:

What are the odds of approval in Harrow?

77.8%of householder applications approved in Harrow

2,856householder decisions in three years

91.0%decided within eight weeks

1,147certificates of lawful development issued

Harrow is the borough where most larger extensions never need prior approval, and the ones that do are usually refused. It approved 2,222 of 2,856 householder applications in the three years to March 2026 — 77.8%, against 83.0% across London.

Under the neighbour-consultation scheme, 869 larger rear extensions were found to need no prior approval at all — the largest such count of any London borough — while of those that did reach a decision, 62 were granted and 263 refused, a grant rate of 19.1%. Harrow's interwar semi-detached stock is the reason: generous rear gardens mean a great many extensions fall inside the ordinary permitted-development limits, and the ones that do not are usually pushing well past what the neighbours will accept.

Watch the timetable here more than elsewhere in outer London. 91.0% of householder applications were decided inside eight weeks, but 4.9% ran past thirteen weeks — a higher tail than most boroughs, and long enough to matter if a builder is booked.

Source: MHCLG District Planning Application Statistics (PS1 and PS2), the statutory return every English planning authority files. Figures cover the twelve quarters to March 2026 and are decisions made in that window, not applications submitted. Published under the Open Government Licence v3.0.

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