Loft Conversion Drawings in Harrow

Where in Harrow does a loft conversion actually get determined?

The Harrow postcode districts we draw in are listed below with the housing that fills each one and the authority determining an application from it. Sums in the table are the statutory England application fees set for 2026, which is a different thing from what a loft costs.

What changes about a loft conversion in each part of Harrow?

Two roofs on the same Harrow road can take different conversions. Ridge height differs, the framing beneath differs, and the depth available behind the house differs, which between them fix what is buildable at a given address.

• Pinner (HA5) — Tudor and 1930s village defines Pinner, where tudor fragments, edwardian villas, 1930s semi-detached set what a loft conversion can do. Edwardian roofs run deeper front-to-back across HA5. Any Pinner loft conversion is validated by Harrow Council, with Pinner High Street the usual Pinner reference point on the site plan.
• Stanmore (HA7) — a loft conversion in Stanmore starts from 1930s semi-detached, edwardian villas, and Stanmore reads as 1930s semi-detached, Green Belt fringe. Edwardian roofs run deeper front-to-back in HA7. Harrow Council assesses Stanmore loft conversions against its own Stanmore character guidance, and the location plan we draw for Stanmore references Stanmore Tube.
• Harrow Weald (HA3) — a loft conversion in Harrow Weald starts from 1930s semi-detached, and Harrow Weald reads as 1930s semi-detached, Green Belt. The 1930s hipped roof here needs a hip-to-gable before a rear dormer works in HA3. Harrow Council assesses Harrow Weald loft conversions against its own Harrow Weald character guidance, and the location plan we draw for Harrow Weald references Harrow Weald Common.
• Kenton (HA3) — a loft conversion in Kenton starts from 1930s semi-detached, and Kenton reads as 1930s semi-detached. The 1930s hipped roof here needs a hip-to-gable before a rear dormer works in HA3. Harrow Council assesses Kenton loft conversions against its own Kenton character guidance, and the location plan we draw for Kenton references Kenton station.
• Wealdstone (HA3) — loft conversion work in Wealdstone means 1930s semi-detached, post-war flats. Wealdstone is 1930s semi-detached, post-war. The 1930s hipped roof here needs a hip-to-gable before a rear dormer works throughout HA3. Harrow Council decides the Wealdstone application, and Wealdstone High Street anchors the Wealdstone location plan.
• North Harrow (HA2) — 1930s semi-detached defines North Harrow, where 1930s semi-detached set what a loft conversion can do. The 1930s hipped roof here needs a hip-to-gable before a rear dormer works across HA2. Any North Harrow loft conversion is validated by Harrow Council, with North Harrow Tube the usual North Harrow reference point on the site plan.
• South Harrow (HA2) — 1930s semi-detached defines South Harrow, where 1930s semi-detached set what a loft conversion can do. The 1930s hipped roof here needs a hip-to-gable before a rear dormer works across HA2. Any South Harrow loft conversion is validated by Harrow Council, with South Harrow Tube the usual South Harrow reference point on the site plan.

How do conservation areas and Article 4 affect a loft conversion in Harrow?

Designation in Harrow: twenty-nine conservation areas cover parts of the borough, including the village core at Pinner and the older parts of Stanmore and Harrow Weald. Inside any of them permitted development is not available for a loft, so the route becomes a householder application. The householder application fee in England is £548, decided in 8 weeks. It does not become a prior approval. A prior approval at £249 covers larger rear extensions notified to neighbours; no roof conversion has ever been consented that way.

No blanket Article 4 over Harrow: Harrow Council has not withdrawn permitted development across Harrow, so a loft conversion outside a Harrow conservation area usually keeps it. The £274 Lawful Development Certificate is still the document a HA1 owner wants on file.

What Harrow is built from: 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. Outer north-west London suburban; Harrow on the Hill has exceptionally strict heritage controls; rest of borough permissive. That mix decides the loft conversion route in Harrow more than the postcode does, and it is what a Harrow Council case officer reads first. A householder application costs £548 paid to Harrow Council direct, with 8 weeks to a decision once validated.

Who decides a loft conversion on the edge of Harrow?

• Hillingdon — cross the Harrow boundary and Hillingdon Council takes the loft conversion instead, applying 29 conservation areas of its own around HA4. We re-price loft conversions at the Harrow edge because Hillingdon policy and Harrow policy rarely align on loft conversion depth.
• Barnet — cross the Harrow boundary and Barnet Council takes the loft conversion instead, applying 20 conservation areas of its own around N2. We re-price loft conversions at the Harrow edge because Barnet policy and Harrow policy rarely align on loft conversion depth.
• Brent — the Brent boundary runs against Harrow, so a loft conversion a street from Harrow is decided by Brent Council instead. Brent runs 22 conservation areas across NW2 and its neighbours, which is why loft conversions priced for Harrow are re-checked against Brent policy whenever the Harrow address sits on that edge.

Sources for this Harrow loft conversion page: borough policies maps and conservation-area registers (2025–26), Royal Mail postcode district boundaries, the Town and Country Planning (Fees for Applications) (England) Regulations, the Town and Country Planning (General Permitted Development) (England) Order 2015 as amended, and the Party Wall etc. Act 1996.