HMO Conversions Pinner

HMO conversion in Pinner changed on 12 June 2026. Harrow's immediate Article 4 Direction on small HMOs covers the whole borough, so turning a Pinner family house into a shared house for three to six people now needs planning permission, and Policy HO10 sets a high bar for it. Licensing, room sizes and fire standards then decide the layout. We build HMO conversions and licence upgrades to the consent and licence conditions the landlord or their agent obtains.

In Pinner, a light HMO conversion for four to six tenants typically costs £40,000 to £75,000 in construction, or £90,000 to £150,000 with an en-suite to every bedroom (indicative London ranges, Mayfair Studio and LetCompliance, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Pinner: we build the fire doors, detection, bathrooms and kitchens to the council's HMO standards, the landlord applies for the licence, and a registered electrician certifies the electrics.

Harrow's small HMO Article 4 direction and a Pinner house

Converting a Pinner house into a small HMO is no longer permitted development. Class L of the General Permitted Development Order 2015 normally allows a change from a C3 dwellinghouse to a C4 house in multiple occupation. Harrow has removed that right across the whole borough with an immediate direction, so since 12 June 2026 a new small HMO needs planning permission. Harrow has been consulting on making it permanent and must decide whether to confirm it by 11 December 2026.

Size of household sets the planning class. The London Plan glossary defines HMOs for three to six people as Use Class C4 and HMOs for more than six people as Sui Generis, which needs planning permission in any case. Nor can Class L be used to split one former family house into several separate C4 HMOs. For a Pinner investor, that means the planning route is fixed before the purchase, not after the builders arrive.

Housing in Pinner

Pinner has around 11,760 homes on the Council Tax list: 43% post-war, 39% interwar and 18% predate 1919, with 36% flats and 64% houses.

Policy HO10 floor area, PTAL and concentration tests in Pinner

Policy HO10 then decides whether a Pinner HMO is supportable at all. Two tests come first: the house as originally built must have more than 130m2 of internal floor, and the site needs a PTAL of 4 to 6. A third looks at the street, where three HMOs or more within the ten closest properties count as over concentration. A modest interwar semi on a street away from the station can fail on area or PTAL before layout is even discussed, so the landlord's designer tests both early.

The strategic picture points both ways. London Plan Policy H9 asks boroughs to recognise the part HMOs play in meeting housing need, and says those of a reasonable standard should generally be protected. The London Plan also asks boroughs weighing C3 to C4 Article 4 Directions to consider the strategic importance of HMOs. For an existing lawful HMO in Pinner, an upgrade to licence standards is often a more realistic project than creating a new one.

Mandatory and additional HMO licensing for a Pinner landlord

Licensing sits on top of planning, and the landlord applies for it. GOV.UK treats an HMO let to 5 or more people from more than 1 household as a large HMO, and that needs a mandatory licence. Harrow's additional scheme reached further down, to smaller HMOs with three or more occupiers in two or more households. That borough-wide designation started on 6 August 2021 and, unless extended, lapsed on 5 August 2026. Harrow ran a consultation on a renewal between 19 December 2025 and 27 February 2026, so check whether a renewed scheme is now in force.

The mandatory scheme stops short of flats in purpose-built blocks of three or more self-contained flats, which only an additional licensing scheme can catch.

Harrow now ties the two together. A new licence for up to 6 occupiers applied for on or after 12 June 2026 needs planning permission behind it, and without that permission Harrow may issue a licence lasting no more than one year. Letting an HMO without a licence risks an unlimited fine, according to GOV.UK. We price and programme the works so the Pinner house meets the licence conditions on the day of the inspection.

Room sizes, shared kitchens and fire safety in a Pinner HMO

Harrow's HMO standards fix the room plan of a Pinner HMO. Harrow sets 6.51 square metres as the minimum for a room slept in by one person over 10, measured without any en-suite, in line with the national licence minimums of 10.22 for two and no sleeping room under 4.64. Ceiling height must reach 1.9m across at least half the floor, and any floor below 1.5m of headroom is left out of the count, which can rule out rooms in a roof. One kitchen or other set of facilities may serve at most 5 people, so a six-bed house needs a second kitchen or cooking area.

The other half of the build is fire protection. The recognised guide is the LACORS housing fire safety guidance, read with Part B of the building regulations: fire doors with self-closers to each letting, a protected escape stair, and interlinked smoke and heat detection. Sound insulation between lettings keeps complaints down. Where the HMO needs an EPC, the MEES Regulations apply too, with no letting below band E since 1 April 2020 without a valid exemption.

• En-suite shower rooms added to bedrooms
• Protected escape routes through the hall, stair and landings
• Interlinked smoke and heat alarms, mains-wired and graded to the council's HMO fire guidance

VOA Council Tax stock of properties, March 2025, for Pinner Green, Pinner Central, Pinner Road and Pinner South. Counts rounded by the VOA.

When comparing hmo conversions in Pinner with other work, it helps to read bathroom renovation in Pinner, hmo conversions across Harrow, bathroom fitting in London, what a kitchen fit covers, how we handle hmo conversions across London and Central Heating Installation Cost.

The GS Renovation Difference in Pinner

An HMO is judged by the licensing officer's inspection as much as by the tenants. We build to the planning consent and to Harrow's room size, amenity and fire standards. The fire doors, detection and escape route are finished before the inspection, and we hand over the fire alarm, electrical and gas certificates the licence file needs. The landlord or their agent makes the planning and licence applications; we supply the drawings and programme they ask for.

• EPC upgrades done while the walls and floors are still open
• Kitchens and bathrooms counted against the council's amenity standard
• Dust screens and floor protection in occupied homes

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254).