HMO Conversions Forest Hill

HMO conversion in Forest Hill starts with planning permission, because Lewisham has removed the right to turn a house into a small HMO across the whole borough. Policy HO8 then supports small HMOs only where the original house has 130 square metres or more of floor, which points to the larger Victorian houses rather than small terraces. Licensing follows, mandatory for large HMOs with Lewisham's own schemes below that. We build to the approved plans and the licence standards, and the landlord or their agent applies for both.

In Forest 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 Forest 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.

Planning permission for an HMO anywhere in Forest Hill

Nationally, Class L of the General Permitted Development Order 2015 lets a dwelling house (C3) become a small HMO (C4) without planning permission. In Lewisham that right has gone. Lewisham's second Article 4 Direction on small HMOs took effect on 19 January 2024 and reaches every part of the borough the first direction, for the Southern Wards (old ward boundaries), left out. Nowhere in Lewisham, Forest Hill included, can a family house switch to a shared house under permitted development, so the owner or their agent has to apply for consent.

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 Lewisham Council, and carrying it out without consent is a criminal offence.

Larger HMOs were never permitted development. 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. A Forest Hill house for seven or more sharers needs its own planning permission whatever the Article 4 position. Class L also does not permit a single house to become two or more separate C4 HMOs. We price the build only against the approved use and occupancy, because the number of bedrooms drives the fire, kitchen and bathroom provision.

Housing in Forest Hill

Roughly 11,040 dwellings sit on the valuation list for Forest Hill. 42% are houses and 58% flats, and by age 54% predate 1919, 13% are interwar and 30% post-war.

Which Forest Hill houses are big enough for a small HMO

Policy HO8 only supports a small C4 HMO where the house as first built had at least 130 square metres of gross internal floor, and space added by a rear or roof extension does not count towards that total. In the VOA statistical areas for Forest Hill, which also take in Honor Oak, 28% of homes are terraced houses and 14% are semi-detached or detached, and only the bigger of those houses will clear that figure. The designer measures the original house, leaving out later extensions, before any layout is drawn.

London Plan Policy H9 says boroughs should take account of the role of HMOs in meeting housing needs, and that HMOs of a reasonable standard should generally be protected. For the owner of a lawful HMO in Forest Hill, upgrading it to current licence standards can be simpler than starting a new one. That work is fire doors and detection, extra bathrooms, larger kitchens and better heating and insulation, carried out while rooms are empty between lets so the house stays in use.

Licensing a Forest Hill HMO: mandatory, additional and selective

Licensing sits alongside planning and has its own thresholds. 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 who form more than 1 household, needs a mandatory licence. Lewisham's Additional HMO licensing scheme came into force on Tuesday 5 April 2022 for HMOs not captured by the National Mandatory Scheme. It applies where three or four people who are not one household share kitchen, toilet or bathroom facilities, so check a Forest Hill address with the council.

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.

Lewisham also runs a selective licensing scheme, in effect from 1 July 2024 and covering around 20,000 properties, so a let house outside the HMO schemes may still need a licence. The landlord applies for whichever licence fits, and we build to its conditions. GOV.UK says renting out an unlicensed HMO can lead to an unlimited fine, so the licence position for a Forest Hill house is settled before tenants move in, and the works are finished before the licensing inspection.

Room sizes, kitchens, bathrooms and fire safety in a Forest Hill HMO

Lewisham's HMO standards set the sizes. A single bedroom in a shared house with a separate kitchen, bathroom and living space needs at least 6.51m2, and a double needs 10.22m2, the same sizes the national licence conditions set, and no room under 4.64m2 may be used for sleeping. Shared kitchens need at least 6.51m2 for up to five people and 11m2 for up to ten, and there must be at least one fixed bath or shower for every five occupants. In a Forest Hill villa, the back addition and a second bathroom on the half landing are where that extra provision tends to go.

Fire safety carries the most weight in the build. Bedroom doors onto the escape route become fire doors with self-closers, the stair is enclosed as a protected route, and interlinked detection and alarms cover the rooms and the escape route. That follows building regulations Part B, the council's HMO fire standards and the LACORS housing fire safety guidance. Lewisham's HMO standards expect a licensed HMO to have an EPC rating of E or better unless an exemption applies, so insulation and heating controls go in during the conversion, alongside sound insulation between the lettings.

• Self-closing fire doors and frames to every bedroom and the kitchen
• Hot water sized for several sharers showering at once, with any gas work by a Gas Safe registered engineer
• Hard-wearing floors, finishes and decoration for a let house

VOA Council Tax stock of properties, March 2025, for Forest Hill West, Forest Hill East and Honor Oak. Counts rounded by the VOA.

Before committing to hmo conversions in Forest Hill, it is worth looking at bathroom renovation in Forest Hill, hmo conversions across Lewisham, bathroom fitting in London, what a kitchen fit covers, how we handle hmo conversions across London and Renovation Budget & Contingency.

Why Choose GS Renovation in Forest Hill

An HMO is checked twice, once by building control and again for the licence. We build with both in mind, fitting fire doors, detection and escape routes to the approved drawings and booking each building control visit before the work is covered. We survey the house with you before quoting, measure each room against the standards the licence will apply, and sequence the work so the rooms are ready by the licensing inspection. A registered electrician certifies the alarm system and wiring.

• EPC upgrades done while the walls and floors are still open
• Materials priced at options, so you choose the finish
• 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).