- Additional licensing
- A council scheme that requires a licence for HMOs outside mandatory licensing, usually smaller HMOs with three or four occupiers, in all or part of the council's area. The council must consult and meet legal tests first. Since 23 December 2024 councils can make schemes of any size without Secretary of State approval.
- Amenity standards
- The standards a council uses to decide whether an HMO has enough kitchens, cooking space, bathrooms, toilets and wash basins for the number of people living there. Each council publishes its own, and they can go further than the national minimum room sizes, so check the standards for the council where the house is.
- Article 4 direction
- A planning direction that removes a permitted development right in a defined area. For HMOs it usually removes the Class L right to turn a house in use class C3 into a small HMO in use class C4, so a planning application is needed. A direction does not ban HMOs.
- Assured periodic tenancy
- The standard private tenancy in England since 1 May 2026, when the Renters' Rights Act 2025 ended fixed terms and section 21 evictions for most private tenancies. It runs from one rent period to the next with no end date. Tenants can leave on two months' notice, and landlords need a legal possession ground to end it.
- Building control and registered building control approver
- Building control is the checking and sign-off of building work against the Building Regulations 2010. It is done by the council's building control service or by a registered building control approver, a private body that gives the council an initial notice. HMO conversions often need it, for example for fire separation, structural changes and drainage.
- Civil penalty
- A fine a council can impose as an alternative to prosecution for certain housing offences, including HMO licensing offences, breaches of the HMO management regulations, failing to comply with an improvement notice and breaching an overcrowding notice. Since 1 May 2026 the maximum civil penalty is £40,000.
- Class L permitted development
- The national planning right, in Schedule 2, Part 3, Class L of the General Permitted Development Order 2015, to change a house from use class C3 to a small HMO in use class C4, or back again, without a planning application. It does not apply where an Article 4 direction has removed it.
- Communal space
- The shared parts of an HMO that all occupiers use, such as the kitchen, dining or living room, hallways and stairs. Councils look at communal space alongside bedroom sizes and shared facilities when deciding how many people a house is suitable for, so check your council's own standards before planning the layout.
- Company let and head lease
- A company let is a letting to a company rather than a person. It cannot be an assured tenancy, so the lease terms govern it. A head lease is the lease from an owner to an operator, who then lets the rooms to occupiers. Guaranteed rent arrangements usually work this way, so have your own solicitor review the lease.
- Compartmentation
- Dividing a building into fire-resisting sections, using walls, floors, ceilings and doors that hold back fire and smoke for a set time. In an HMO it protects the escape route and slows fire spreading between rooms. Gaps where pipes and cables pass through must be fire-stopped to keep it effective.
- Completion certificate
- The certificate confirming that finished building work meets the Building Regulations. Council building control issues a completion certificate; a registered building control approver issues a final certificate. For an HMO conversion, keep it with your other compliance records, as councils, lenders, insurers and buyers may ask to see it.
- Council tax Class C
- The rule, in Class C of the Council Tax (Liability for Owners) Regulations 1992, that makes the owner rather than the occupiers liable for council tax where a house is let room by room or was built or adapted for multiple occupation. With a whole-house joint tenancy the occupiers may be liable instead. The council decides each case.
- Deposit protection
- The legal duty to protect a tenant's deposit in a government-approved tenancy deposit scheme within 30 days of receiving it, and to give the tenant the required information about the scheme. Under the Tenant Fees Act 2019 a tenancy deposit is capped at five weeks' rent where the annual rent is under £50,000.
- EICR
- An Electrical Installation Condition Report: a qualified person's report on the condition of the fixed electrical installation. Private landlords in England need one before a tenancy starts and at least every five years, must give tenants a copy within 28 days, and must complete remedial work within 28 days or sooner if the report says so.
- Emergency lighting
- Lighting that comes on automatically if the mains supply fails, so occupiers can see their way out. Whether an HMO needs it depends on the fire risk assessment, the layout and the council's standards. It is more often needed in larger houses and where the escape route is long or has little natural light.
- En-suite
- A private shower room with a toilet and basin that opens off one bedroom. In an HMO it reduces demand on shared bathrooms and may count towards the council's amenity standards. Adding one usually involves new drainage, ventilation and electrical work, which may need building regulations approval.
- EPC and MEES
- An Energy Performance Certificate rates a property's energy efficiency from A to G. Under the Minimum Energy Efficiency Standards a private landlord cannot let a property rated F or G unless a valid exemption is registered. A minimum of EPC C by 1 October 2030 is confirmed government policy but still needs legislation.
- Fire door
- A door and frame made to resist fire for a set time, such as FD30 for 30 minutes, usually with intumescent strips and a self-closer. Fire doors (typically FD30 or FD30S with self-closers) are commonly required in HMOs, depending on the property's layout, size and fire risk assessment, and the council's HMO standards.
- Fire risk assessment
- A written review of fire hazards, the people at risk and the precautions in place, with actions to reduce the risk. Where the Fire Safety Order applies, the responsible person must carry one out for the common parts of an HMO and keep it up to date. It also guides decisions on doors, alarms and lighting.
- Fire Safety Order and responsible person
- The Regulatory Reform (Fire Safety) Order 2005 covers the common parts of HMOs and of buildings with two or more homes. The responsible person, usually the landlord or managing agent, must carry out a fire risk assessment and act on it. Fire and rescue authorities enforce it. It may apply differently to a whole house let to one group.
- Fit and proper person
- The test a council applies to a proposed licence holder and manager. It considers offences involving fraud, dishonesty, violence, drugs and certain sexual offences, unlawful discrimination, and breaches of housing law, landlord and tenant law or an approved code of practice. Anyone subject to a banning order is automatically not fit and proper.
- Gas safety record
- The record a Gas Safe registered engineer produces after checking every gas appliance and flue in a let property. Landlords must have the check done at least every 12 months, give existing tenants a copy within 28 days, give new tenants one before they move in, and keep each record until two further checks are done.
- General Approval 2024
- The government approval, in effect from 23 December 2024, that lets councils in England make additional and selective licensing schemes of any size without asking the Secretary of State to confirm them. Councils must still consult and meet the legal tests before a scheme can start.
- Gross yield and net yield
- Gross yield is the annual rent divided by the purchase price or total cost, shown as a percentage. Net yield takes off running costs first, such as council tax, utilities, insurance, management, maintenance, licensing and voids. For an HMO, where the owner often pays the bills, net yield gives a truer picture.
- Ground 4A
- A mandatory possession ground for student lets in HMOs, in force since 1 May 2026. Conditions include: every tenant is, or is expected to become, a full-time student; written notice is given before the tenancy is signed; it is signed no more than six months before move-in; and the relevant date falls between 1 June and 30 September.
- Guaranteed rent
- An arrangement where an operator, usually a company, leases a property from the owner, pays an agreed rent whether or not the rooms are let, and lets the rooms itself. It is usually a company let governed by the lease terms, not an assured tenancy. Owners should have the lease reviewed by their own solicitor before signing.
- HHSRS and Category 1 hazard
- The Housing Health and Safety Rating System is the risk-based method councils use to assess hazards in homes; a revised version with 21 hazards took effect on 23 June 2026. A Category 1 hazard is the most serious kind. A council must take action when it finds one, such as serving an improvement notice.
- HMO
- A house in multiple occupation: a property let to at least three people who form more than one household and share a kitchen, bathroom or toilet, living there as their only or main home. Converted blocks of flats can also be HMOs under section 257. The legal definition is in the Housing Act 2004.
- Household
- For HMO law, a single person or members of the same family living together, including couples and certain relatives such as parents, children, siblings and cousins. Unrelated sharers each form a separate household, which is why three friends sharing a house can make it an HMO.
- Interlinked alarm
- A fire alarm system where the detectors are connected, by wiring or radio, so that when one detects fire they all sound. A mains-wired interlinked system is commonly required in HMOs, with the type and coverage depending on the layout, size and fire risk assessment, and the council's HMO standards.
- LACORS guidance
- The Housing: Fire Safety guidance published by LACORS in 2008, which councils still widely use as their benchmark for fire safety in existing HMOs and shared houses. It is risk-based rather than prescriptive, so the doors, alarms and escape route a house needs depend on its layout, size and fire risk assessment.
- Large HMO
- An HMO with seven or more residents. For planning it falls outside use class C4 and is sui generis, so creating one always needs planning permission. With five or more occupiers forming two or more households, it also needs a mandatory HMO licence from the council.
- Lawful development certificate
- A certificate from the council confirming that an existing or proposed use, or building work, is lawful for planning purposes. HMO owners use one to show that a house became a small HMO lawfully, for example before an Article 4 direction took effect, or that a proposed change does not need planning permission.
- Licence conditions
- The conditions attached to an HMO licence that the licence holder must keep to. Mandatory conditions cover gas safety, safe electrical appliances and furniture, smoke and CO alarms, a written statement of terms for occupiers and minimum room sizes. Councils add their own conditions, and breaching any condition is an offence.
- Licence holder and manager
- The licence holder is the person named on an HMO licence and responsible for its conditions, usually the owner or a managing agent. The manager is the person who manages the HMO and must meet the HMO management regulations. The council checks that both are fit and proper before granting a licence.
- Management Regulations 2006
- The Management of Houses in Multiple Occupation (England) Regulations 2006, which apply to every HMO in England except section 257 blocks, licensed or not. The manager must give contact details, keep escape routes and fire safety measures in order, maintain water, drainage, gas, electricity, common parts and rooms, and provide waste facilities.
- Mandatory licensing
- The national requirement for an HMO licence where five or more people forming two or more households live in the property and share facilities. It applies in every council area in England. A licence lasts up to five years, and running an unlicensed HMO is an offence that can lead to fines and rent repayment orders.
- Material change of use
- A change in how a building is used that triggers legal controls. In planning, it is a change significant enough to need permission. Under the Building Regulations 2010 it includes changing the number of dwellings or creating rooms for residential purposes, such as bedsit lettings. An HMO conversion may be one, depending on the facts.
- Minimum room sizes and 1.5 metre ceiling rule
- The national minimum bedroom sizes in every HMO licence since 1 October 2018: 6.51 m² for one person over 10, 10.22 m² for two people over 10, and 4.64 m² for a child under 10. Rooms under 4.64 m² cannot be used for sleeping, and floor area under a ceiling lower than 1.5 metres does not count.
- Occupier
- A person living in an HMO as their only or main home, whether under a tenancy or a licence. Licensing thresholds count occupiers, including children, so a couple with a child counts as three people forming one household. Occupiers also have their own duties under the HMO management regulations.
- Protected escape route
- The route from the rooms to a final exit, usually the hallway and stairs, protected by fire-resisting walls, ceilings and doors so people can get out safely. It is central to fire safety in most HMOs, and the manager must keep it clear and in good repair.
- PRS Database
- The private rented sector database set up under the Renters' Rights Act 2025, where landlords will register themselves and their rental properties. It is due to open on 15 December 2026, starting in the West Midlands, and then roll out region by region, subject to Parliament approving the regulations.
- PRS Landlord Ombudsman
- A new ombudsman service under the Renters' Rights Act 2025 that private landlords will have to join, so tenants can take complaints about their landlord to an independent body. It is not live yet. The government expects membership to become mandatory in 2028.
- Redress scheme and client money protection
- A redress scheme is a government-approved complaints service that letting agents and property managers must belong to. Client money protection is a scheme that agents holding client money, such as rent and deposits, must belong to. Agents must publish both scheme names, with their fees, on their website and at their offices.
- Rent repayment order
- An order from the First-tier Tribunal that a landlord repay rent, for example for running an unlicensed HMO. Since 1 May 2026 an order can cover up to two years' rent, applications can be made up to two years after the offence, and orders can be made against superior landlords and, in some cases, company directors.
- Rent-to-rent
- A business model where an operator rents a property from the owner, usually as a company let, and sublets the rooms for more than it pays. Since 1 May 2026 owners, as superior landlords, can face licensing offences and rent repayment orders, for example where the house is not properly licensed, so have any arrangement checked by your own solicitor.
- Renters' Rights Act 2025
- The Act that reformed private renting in England. Its main tenancy changes took effect on 1 May 2026: section 21 abolished, assured periodic tenancies, one rent rise a year by section 13 notice, no rental bidding, limits on rent in advance, no blanket bans on children or benefits, and pets not unreasonably refused.
- Right to Rent
- The legal duty on landlords and letting agents in England to check that each adult who will live in a rented home has the right to rent in the UK before the tenancy starts, and to keep a record of the check. Penalties apply for letting to someone without that right.
- Section 13 notice
- The formal notice, under section 13 of the Housing Act 1988, that a landlord uses to increase the rent on an assured periodic tenancy. Since 1 May 2026 rent can rise only once a year this way, with at least two months' notice, and the tenant can challenge the increase at the First-tier Tribunal.
- Section 257 HMO
- A building converted into self-contained flats where the conversion did not meet the building standards of the time, such as the 1991 Building Regulations, and still does not, and fewer than two-thirds of the flats are owner-occupied. These blocks fall outside mandatory licensing, use class C4 and the 2006 Management Regulations.
- Selective licensing
- A council scheme that requires privately rented homes in a designated area to hold a licence, including homes that are not HMOs. It is aimed at local problems such as poor property conditions or antisocial behaviour. Since 23 December 2024 councils can make schemes of any size without Secretary of State approval.
- Self-closer and intumescent strip
- A self-closer is a device that pulls a door fully shut into its frame after each use, so a fire door can do its job. An intumescent strip is a seal set into the door or frame edge that swells when heated to close the gap. Fire doors in HMOs commonly need both.
- Small HMO
- An HMO with three to six residents. For planning it falls in use class C4, and changing a family house to a small HMO is permitted development unless an Article 4 direction applies. It needs a licence if five or six people live there, or if the council runs additional licensing that covers it.
- Smoke and CO alarm regulations
- The Smoke and Carbon Monoxide Alarm (England) Regulations 2015, as amended in 2022. Landlords must fit a smoke alarm on every storey with living accommodation and a CO alarm in rooms with a fixed combustion appliance other than a gas cooker, check alarms work at each new tenancy, and repair faults. Licensed HMOs meet the same duties through licence conditions.
- Sui generis
- Latin for 'of its own kind'. In planning, a use that fits no use class, so changing to it generally needs planning permission. Large HMOs with seven or more residents are sui generis, which is why creating one always needs a planning application.
- Superior landlord
- A landlord higher up a chain of leases, such as an owner who leases a house to a rent-to-rent operator. Since 1 May 2026 superior landlords can commit HMO licensing offences and face rent repayment orders, though defences are available, for example where they had no reason to know the property was an HMO.
- Tenant Fees Act 2019
- The Act that bans most fees to tenants in England. Landlords and agents can only take permitted payments, including rent, a refundable deposit capped at five weeks' rent where annual rent is under £50,000, a holding deposit of up to one week's rent, and certain other payments the Act sets out.
- Use class C3
- The planning use class for dwellinghouses: a home lived in by a single household, or by up to six residents living together as a single household. Most family houses are in use class C3 before they are converted to an HMO.
- Use class C4
- The planning use class for small HMOs: a house shared as an HMO by three to six residents who do not form a single household. Changing between C3 and C4 is permitted development under Class L unless an Article 4 direction applies. Section 257 converted blocks of flats are excluded from C4.
- Void
- A period when a room or property is empty and earns no rent, for example between tenants or during works. Costs such as council tax, utilities and finance usually continue during a void, so void periods matter when working out an HMO's likely net yield.
HMO glossary
Definitions of the terms you will meet when converting, licensing or letting a house in multiple occupation in England.
Planning an HMO in the Midlands?
Book a free survey. We measure every room, check the licensing and planning position, and give you a fixed written quote.
