HMO Conversions Southwark

HMO conversion in Southwark is shaped more by licensing than by planning. The borough's additional licensing designation covers the whole of Southwark and runs from 1 March 2022 to 1 March 2027 unless revoked earlier, so even a small HMO needs a licence. Planning bites where an HMO Article 4 direction applies, as on Henshaw Street and Bywater Place, and on any HMO for 7 or more people, and the council's HMO Standards set room sizes, kitchens and bathrooms.

In Southwark, 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 Southwark: 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.

When a Southwark HMO needs planning permission

Outside the Article 4 direction areas, a small HMO in Southwark can be created without planning permission, but every HMO for 7 or more people needs it. A house shared by three to six people is Class C4, and Class L of the GPDO makes the change from C3 permitted development unless an Article 4 direction applies. Henshaw Street in SE17 has a direction covering a change to a small HMO for 4 to 6 people and back again, and Bywater Place in Surrey Docks, SE16 covers 3 to 6 people.

If the building is listed, the works themselves are a separate question: anything that affects its character, inside or out, needs listed building consent from Southwark Council, and carrying it out without consent is a criminal offence.

Southwark also needs planning permission to let a property as an HMO to 7 or more people, because the London Plan treats HMOs for more than six as sui generis. Class L does not let one former house become two or more separate C4 HMOs either. Where permission is needed, Policy P9 of the Southwark Plan 2022 asks for communal indoor and outdoor space, refuse and recycling storage and one cycle parking space per occupant, and no overconcentration of HMOs locally.

Housing in Southwark

On the valuation list Southwark counts about 149,990 homes, 81% flats and 19% houses; 25% predate 1919, 7% are interwar and 64% post-war.

Mandatory and additional HMO licensing across Southwark

In Southwark a shared house of any size can need a licence, because two schemes overlap. A large HMO, rented to 5 or more people who form more than 1 household, needs a mandatory licence under national law. Below that, Southwark's additional licensing designation, made on 28 October 2021, covers HMOs let to a maximum of 4 people who share bathrooms or kitchens, and it applies to the entire borough.

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.

The additional designation came into force on 1 March 2022 and ceases to have effect on 1 March 2027 unless the council revokes it earlier, so check its status before you let. Renting out an unlicensed HMO can lead to an unlimited fine. The landlord or their agent applies for the licence; we build the rooms, kitchens, bathrooms and fire protection to the standards the licence will carry, and hand over the certificates the application needs.

Room sizes, kitchens and bathrooms under Southwark HMO Standards

Southwark's HMO Standards set the numbers that decide how many people a house can take. A single letting room needs at least 10 square metres and a double at least 14 square metres where the kitchen is in a separate room. Rooms should have a ceiling of at least 2.3 metres over at least half of the habitable floor area, which can rule out low attic rooms and cellar rooms under the ground floor, however large they are. They sit above the national minimums every mandatory licence carries, 6.51 square metres for one adult, 10.22 for two and no sleeping room under 4.64, so design to Southwark's.

Shared facilities scale with the occupants. Where exclusive facilities cannot be provided, the standards ask for one bathroom or shower room, one toilet and one wash hand basin for every 5 occupants, and one set of kitchen facilities for every 5 occupants. On a six person house that means a second bathroom and a larger kitchen, so we plan the drainage runs, extract fans and worktop lengths at the survey, before any room is divided.

Fire safety, sound and energy in a Southwark shared house

Fire protection is the biggest single package in a Southwark HMO conversion, and the licence conditions depend on it. The usual scope is fire doors with self closers to every letting room and the kitchen, an interlinked fire detection and alarm system, a protected escape route down the stair, and fire stopping where services pass through walls and floors. LACORS housing fire safety guidance is the recognised guide that councils and designers work from, and building regulations Part B applies to the alterations.

Sound and energy come next. Tenants on different timetables share walls and floors, so we add insulation and resilient layers between letting rooms where the layout puts a bedroom next to a kitchen or bathroom. The house must also be lettable on energy: Southwark states it is illegal for a domestic landlord to let a property with an EPC rating of F or G, unless a valid exemption applies. Insulation and heating upgrades therefore go into the same programme.

• En-suite shower rooms added to bedrooms
• Separate WCs and wash basins to the amenity standard
• Insulation and heating upgrades toward the minimum EPC for letting

VOA Council Tax stock of properties, March 2025, for all 34 statistical areas in Southwark. Counts rounded by the VOA.

Before committing to hmo conversions in Southwark, it is worth looking at bathroom renovation in Southwark, our Southwark area guide, what a main building contractor does, what a kitchen fit covers, hmo conversions across London and Bathroom Renovation Cost.

Why Choose GS Renovation in Southwark

An HMO conversion is built to a licence as much as to drawings, so we work from the standards from the first survey. We lay out rooms to Southwark's sizes, plan bathrooms and kitchens for the number of occupants, and build the fire doors, alarms and protected stair the licence will expect. The landlord or their agent applies for the licence and any planning permission, and we hand over the electrical, alarm and gas certificates.

• Finished and snagged before the council's licence inspection
• Fire doors, closers and seals fitted to every door on the escape route
• Dust screens and floor protection in occupied homes

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