HMO Conversions Mill Hill

An HMO conversion in Mill Hill needs planning permission before anything is built, because Barnet Council records a borough-wide Article 4 Direction from May 2016 requiring permission for all future HMOs. That removes the national right to change a family house to a small shared house, so planning comes first, then a build to licence standards, then the licence application. We fit out shared houses to the fire, room and amenity standards the licence will impose, once the owner has consent.

In Mill Hill, 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 Mill Hill: 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.

Barnet's Article 4 and what it means for Mill Hill HMOs

In Mill Hill a new HMO of any size needs planning permission. Nationally, Class L of the General Permitted Development Order 2015 permits a change from Class C3 dwellinghouses to Class C4 houses in multiple occupation without an application. Barnet's Article 4 direction on small HMOs, which the Planning Data record starts on 2016-05-29, removes that right across the borough, so a family house in Mill Hill let to three unrelated sharers needs consent first.

Larger shared houses need permission regardless. The London Plan glossary classes HMOs for three to six people as C4 and those for more than six as Sui Generis. Class L also does not permit one former single house to be used as two or more separate C4 HMOs. Barnet says it will take enforcement action against unauthorised and illegal HMO properties, so a Mill Hill landlord should hold the planning decision in writing before any fit-out is ordered.

Housing in Mill Hill

Around 10,980 homes make up Mill Hill on the valuation list; 44% are flats and 56% houses, and 10% date from before 1919, 38% from between the wars and 52% from after 1945.

HMO licensing for a Mill Hill shared house

Licensing runs alongside planning for a Mill Hill HMO and is a separate process. GOV.UK defines an HMO as a property rented out by at least 3 people who are not from 1 household but share facilities like the bathroom and kitchen. A large HMO, rented to 5 or more people forming more than 1 household, needs a mandatory licence, though a flat in a purpose-built block of three or more flats falls outside mandatory licensing. GOV.UK adds that even a smaller HMO may need a licence depending on the council area.

Barnet Council publishes a register of properties licensed under its HMO Licensing Scheme, updated monthly, as section 232 of the Housing Act 2004 requires. Whether a smaller shared house in Mill Hill falls under a wider council scheme is for the landlord to confirm with Barnet before letting. GOV.UK warns that renting out an unlicensed HMO can lead to an unlimited fine. The landlord applies for the licence; we build to the conditions and standards it sets.

Room sizes, kitchens and bathrooms in a Mill Hill HMO

Room sizes and shared amenities decide how many tenants a Mill Hill house can lawfully take. National minimum bedroom sizes for one and for two adults are mandatory conditions of an HMO licence in England, and very small rooms cannot be used for sleeping at all. The council's own amenity standards then set how many kitchens, sinks, cookers, bathrooms and WCs the house needs per occupant. The designer should draw each room against those figures before the room count is fixed.

In an interwar Mill Hill semi, that often means one bedroom fewer than the estate agent's count, a second bathroom carved from a box room, and a kitchen enlarged into the old dining room so the shared space works. We plan the drainage so extra WCs and showers connect cleanly into the existing stacks, and size hot water for peak demand. Each bedroom usually gets a lock, and some landlords add a basin, which changes the waste runs.

Fire safety, sound and energy in a Mill Hill HMO

Fire safety is the core of an HMO fit-out in Mill Hill. The escape route through the hall and stair is protected, bedroom and kitchen doors become fire doors with self-closers, and interlinked detection and alarms are installed to the grade the design sets. The LACORS housing fire safety guidance is the recognised guide for existing shared houses, read with Part B of the Building Regulations for new work and any fire standards Barnet attaches to the licence.

Sound and energy follow. Tenants in separate lettings hear each other through lightweight partitions and timber floors, so we add insulation to walls between bedrooms and under floors where the specification calls for it. An HMO let in Mill Hill must also meet the minimum energy rules: GOV.UK says that since 1 April 2020 landlords cannot let or continue to let properties covered by the MEES Regulations below E without a valid exemption. For a Mill Hill landlord, getting that order right decides whether the house can be let on the date planned or sits empty waiting for sign-off.

• Service holes sealed so each bedroom and the kitchen stay separate fire compartments
• Hot water sized for several sharers showering at once, with any gas work by a Gas Safe registered engineer
• En-suite shower rooms added to bedrooms

VOA Council Tax stock of properties, March 2025, for Mill Hill Broadway, Mill Hill East and Mill Hill Park. Counts rounded by the VOA.

Useful next reading for a hmo conversions project in Mill Hill: bathroom renovation in Mill Hill, hmo conversions across Barnet, how building control works in London, how snagging works at handover, hmo conversions anywhere in London and House Rewire Cost.

Working With GS Renovation in Mill Hill

An HMO conversion is inspected against the licence as well as building regulations, so the details have to be right the first time. We work from the owner's planning consent and the licence conditions, with one site lead who keeps a photo record of fire doors, detection and fire stopping before they are covered. A registered electrician certifies the installation and alarms, gas work is done by a registered gas engineer, and you receive the certificates the licensing officer will ask to see. In Mill Hill the licensing authority is Barnet Council, so that record is organised around what its officers check at inspection.

• A written scope and programme agreed before work starts
• Sound lining between bedrooms so one sharer does not keep another awake
• En-suites placed only where a soil stack can serve them

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