HMO Conversions Borough

HMO conversion in Borough is a narrow service, because the VOA's count for the wider Borough & Southwark Street and Southwark St George's area has only 6% of homes as houses, all terraced, and the rest as flats. What comes up is a terrace let as a shared house, a flat let to sharers, or an existing HMO upgraded to meet licence conditions. Southwark runs additional HMO licensing across the whole borough and sets its own HMO Standards for rooms, kitchens and bathrooms. The landlord applies for the licence; we build to the standard it assumes.

In Borough, 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 Borough: 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.

Planning for a Borough HMO: Class L, Article 4 and seven sharers

Changing a Borough house from a family home to a small shared house is normally permitted development. Class L of the national order allows a change from Class C3 dwellinghouses to Class C4 houses in multiple occupation, and the London Plan defines C4 as an HMO for three to six people. Class L does not allow one house to become two or more separate HMOs. Southwark says planning permission is needed for an HMO let to 7 or more people, which is sui generis, or for any HMO in an Article 4 direction area.

The two HMO Article 4 directions in our research are for Henshaw Street, SE17, and Bywater Place, Surrey Docks, SE16. Borough is in SE1, so neither is on its streets, but that does not prove no direction covers your address, so ask Southwark's planning department before buying. If a Borough scheme does need permission, Policy P9 of the Southwark Plan 2022 brings further tests: shared living space inside and out, somewhere to store bins and recycling, a bike space for each resident, and no overconcentration of HMOs nearby.

Housing in Borough

Take the 12,140 or so homes the valuation list gives Borough: 94% flats, 6% houses, 18% from before 1919, 3% interwar and 73% post-war.

Which licence a Borough shared house needs

While Southwark's additional scheme runs, a shared house in Borough needs a licence of one kind or another. The national mandatory licence catches the large HMO, meaning 5 or more tenants who make up more than 1 household, though not a flat in a purpose-built block of three or more flats. Below that size, the borough's own designation fills the gap. Southwark made it on 28 October 2021, it took effect on 1 March 2022, and its reach is the whole borough. It captures shared houses with no more than 4 tenants sharing a kitchen or bathroom.

Its expiry date is 1 March 2027, earlier if the council revokes it, so confirm whether a renewal is in place before planning around those dates. The designation also reaches section 257 HMOs, a converted block of at least 3 storeys holding 3 or more self-contained flats with one owner or controller, where the old conversion falls short of current standards. GOV.UK warns that letting an unlicensed HMO risks an unlimited fine. The landlord makes the licence application; our job is to deliver a building that meets the conditions.

Southwark HMO Standards for rooms, kitchens and bathrooms in Borough

Southwark's HMO Standards fix the layout of a Borough shared house before the first stud goes up. With the kitchen in its own room, a letting room for one person must reach 10 square metres, and one for a couple 14 square metres. At least half of each room's habitable floor should have 2.3 metres or more of headroom, which can rule out a low attic or back addition room. Beneath these local figures sit the national licence conditions: 6.51 square metres for one adult, 10.22 for two, and no sleeping room under 4.64.

Facilities rise with headcount. Where tenants cannot each have their own, the Standards set a ratio of 5 occupants to each shared bathroom or shower room, each toilet and each wash hand basin, and the same ratio of 5 to each shared kitchen. In a small Borough terrace, the drainage stack and the kitchen size often decide how many rooms can be let. We set out the rooms against these figures with the landlord's designer before we price the work.

Fire safety, sound and energy in a Borough HMO

Fire safety drives the building work in a Borough HMO. Each letting room gets a fire door with a self closer onto a protected escape route, the stair is enclosed with fire rated linings, and an interlinked fire detection and alarm system covers the rooms, the escape route and the kitchen. The LACORS fire safety guide for housing sets the accepted benchmark, and the council's fire standards and Part B apply where building work is done.

Sound between lettings matters more than in a family home, because each room is a separate household with its own hours. We add acoustic insulation in partitions and floors between rooms, and seal gaps around services. Energy rules apply too: since 1 April 2020 a landlord cannot let, or continue to let, a home rated below EPC E without a valid exemption, and Southwark states that letting a domestic property rated F or G is illegal. We plan insulation and heating upgrades into the conversion.

• Large HMO conversions for seven or more, once planning is granted
• Insulation and heating upgrades toward the minimum EPC for letting
• Hard-wearing floors, finishes and decoration for a let house

VOA Council Tax stock of properties, March 2025, for Borough & Southwark Street and Southwark St George's. Counts rounded by the VOA.

Once the hmo conversions work in Borough is scoped, people usually go on to read bathroom renovation in Borough, hmo conversions across Southwark, bathroom fitting in London, what a snagging list covers, our London hmo conversions page and Central Heating Installation Cost.

The GS Renovation Difference in Borough

An HMO conversion is judged at the licence inspection and in the fire risk assessment, so small details count: door closers, detector positions, fire stopping and room sizes. We survey the house, price it in writing and give a written programme that the landlord's designer and the licensing officer can check against the standards. One team covers the partitions, fire doors, plastering, kitchens, bathrooms and decoration. A registered electrician installs and certifies the alarm circuits and electrics, and gas work goes to an engineer on the Gas Safe Register. The founder is your single contact.

• Neighbours given notice before the noisy stages
• Existing HMOs brought up to licence conditions, fire works first
• Finished and snagged before the council's licence inspection

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