In England, if your shared house (the legal term is HMO) needs a mandatory or additional licence, every licence includes national minimum room sizes for rooms used for sleeping: at least 6.51 square metres for one person aged over 10, at least 10.22 square metres for two people aged over 10, and at least 4.64 square metres for one child under 10. A room smaller than 4.64 square metres can't be used for sleeping at all, and floor space where the ceiling is lower than 1.5 metres doesn't count. These come from the 2018 licence conditions regulations. Your council may expect more.
This guide explains where the rules come from, how to measure a room properly and what happens if a room is too small.
Where the minimum sizes come from
Mandatory licence conditions
The Licensing of Houses in Multiple Occupation (Mandatory Conditions of Licences) (England) Regulations 2018 add conditions to every licence for a shared house granted under Part 2 of the Housing Act 2004, which covers both mandatory and additional licensing. Regulation 2 inserts them into Schedule 4 of the Housing Act 2004 (paragraphs 1A to 1C). They set the room sizes and a condition to follow the council's scheme for storing and disposing of household waste.
Mandatory licensing applies, broadly, to a shared house rented to five or more people who form more than one household and share facilities such as a kitchen or bathroom. The detailed description is in the Licensing of Houses in Multiple Occupation (Prescribed Description) (England) Order 2018, made under section 55 of the Housing Act 2004. See shared house licensing for whether your house needs a licence.
The sizes
From regulation 2, the licence holder must make sure that:
| Who sleeps in the room | Minimum floor area |
|---|---|
| One person aged over 10 | 6.51 m² |
| Two people aged over 10 | 10.22 m² |
| One child aged under 10 | 4.64 m² |
| Any room under 4.64 m² | Not to be used as sleeping accommodation |
Any part of the floor where the ceiling is lower than 1.5 metres isn't counted.
The licence also says the maximum number of people aged over 10, and under 10, who may sleep in each room. A room that's big enough for one adult but not two can only be let to one. You must also tell the council about any room under 4.64 m².
Local standards
Councils can attach their own conditions to licences about how the house is managed, used and occupied (section 67 of the Housing Act 2004). They also decide how many people the house is suitable for, and can't treat it as suitable if it falls short of the national standards for bathrooms, toilets, kitchens and other facilities (section 65). Many councils publish local amenity standards for this, and some go further than the national room sizes. Always check your council's licensing standards before applying.
Additional licensing
Additional licences are also granted under Part 2 of the Housing Act 2004, so the same national room sizes are conditions of an additional licence too. The council can add its own conditions on top. A selective licence (under Part 3) doesn't carry the national room size conditions, though the council can still look at crowding.
How to measure a room
Measuring properly is the difference between a room that complies and one that doesn't. Measure it yourself before you apply, and keep your notes.
Basic rectangle
Measure the length and width at floor level, wall to wall, and multiply. A room 3.2 m by 2.4 m is 7.68 m².
L-shaped and irregular rooms
Split the room into rectangles, measure each, and add them up. Measure built-in cupboards and chimney breasts separately; whether they count depends on the council's approach, so ask.
Sloping ceilings
In loft rooms and rooms under the stairs, find the line on the floor where the ceiling height is exactly 1.5 m. Only the floor on the higher side of that line counts.
Things to watch
- Measure to the walls, not the skirting.
- Don't count the area of a door swing or a bay unless your council does.
- Measure each room separately even if two rooms look identical.
- Keep a simple floor plan with the measurements; councils often ask for one with the application.
If a room is too small
It can't be used for sleeping
A room under the relevant minimum can't be used as sleeping accommodation for that number of people. A room under 4.64 m² can't be used for sleeping at all. It might still be used as a study or storage.
Existing tenants
If a room in a licensed house is being used in breach of the size conditions and the licence holder didn't knowingly allow it, the holder must put it right within the period the council sets when it tells them. That period can't be more than 18 months from the council's notice. Separately, when a house is licensed for the first time, the council can give up to 18 months to meet these conditions; during that period it can't revoke the licence, prosecute or fine you for those conditions. Neither rule lets you knowingly let a room that's too small to a new occupier.
Penalties
Breaking a licence condition without a reasonable excuse is an offence under section 72 of the Housing Act 2004. The council can prosecute, or impose a civil penalty of up to £40,000 instead (section 249A). It can also count against you when the council decides whether you're a fit and proper person to hold a licence. Rent repayment orders aren't available for breaking a licence condition, but they are for letting a house that needs a licence without one.
Houses that don't need a licence
The national minimums are licence conditions, so they apply directly only to licensed houses. Every rented home is still assessed under the housing health and safety rating system, which includes a hazard for crowding and space: a lack of adequate space for living and sleeping (HHSRS regulations, Schedule 1). A tiny bedroom can still be a problem even where no licence is needed.
Other space and facilities
Room size isn't the only thing a council looks at. Licence conditions and local standards usually also cover:
- enough kitchen space and equipment for the number of people;
- enough bathrooms and toilets;
- fire safety, including escape routes (see fire safety in a shared house);
- a suitable place to store rubbish and recycling, which is part of regulation 2.
Before you buy or convert a house
Room sizes decide how many rooms a house can legally let, and so what it can earn. If you're buying a house to let by the room, or converting one, check the numbers before you commit:
- Measure every room yourself rather than relying on the sales particulars, which often round up or measure into bays.
- Check the council's local standards for kitchen and bathroom numbers as well as bedroom sizes. A house with enough bedrooms may still be limited by its kitchen.
- Check planning. Turning a family home into a small shared house (up to six residents) normally doesn't need a planning application, but a council can remove that right in an area with an Article 4 direction. A house for more than six residents isn't covered by that right. GOV.UK explains when planning permission is required.
- Think about who will live there. A double room that meets 10.22 m² can be let to a couple; a room just over 6.51 m² can only ever be let to one adult.
- Allow for fire safety work, which can take space from rooms, such as a protected escape route. See fire safety in a shared house.
Keeping room sizes right over time
Once the licence is granted, its conditions apply for as long as it lasts, which can be up to five years. A few habits help:
- Keep the floor plan and measurements with the licence, and update them if you change the layout.
- When a room is re-let, check the licence still allows the number of people moving in. A couple moving into a single room breaks the condition even if the previous tenant was alone.
- Tell the council before changing the layout of a licensed house; it may need to vary the licence.
- Put the licence end date in your calendar and apply to renew in good time.
Worked example
The house, names and measurements are made up.
Jo is applying for a mandatory licence for a five-bedroom house. Jo measures each room:
| Room | Measurements | Floor area counted | Use |
|---|---|---|---|
| Room 1 | 4.0 m × 3.0 m | 12.00 m² | Double: two adults allowed (over 10.22 m²) |
| Room 2 | 3.0 m × 2.6 m | 7.80 m² | Single: one adult (over 6.51 m², under 10.22 m²) |
| Room 3 | 2.8 m × 2.4 m | 6.72 m² | Single: one adult |
| Room 4 (loft) | 4.2 m × 3.0 m, but ceiling under 1.5 m for the first 1.4 m of the length | 2.8 m × 3.0 m = 8.40 m² | Single: one adult |
| Room 5 | 2.5 m × 1.8 m | 4.50 m² | Too small for sleeping (under 4.64 m²) |
Room 4 looks big, but only 8.40 m² of it counts because of the sloping ceiling. Room 5 can't be a bedroom. Jo turns it into a study for the house and applies for a licence for four rooms and up to five people, checking the council's local standards for kitchen and bathroom numbers.
Jo also checks how the change affects the numbers: with four rooms instead of five, the rents need to work for the house. See how to price a room.
How Rentap helps
In Rentap, each room has its own page with a description and photos, so you can keep its details (such as its measured size and type) where you'll find them. The compliance calendar suggests the shared house licence renewal alongside gas, electrical and alarm checks, lets you upload the licence, and reminds you 60, 30 and 7 days before it's due. Rentap doesn't check room sizes or licence conditions for you. See the compliance calendar, our free compliance calendar tool and pricing.
For terms used here, see the glossary of letting terms.
Sources
- Licensing of HMOs (Mandatory Conditions of Licences) (England) Regulations 2018 (legislation.gov.uk)
- The 2018 Regulations, regulation 2 (legislation.gov.uk)
- Licensing of HMOs (Prescribed Description) (England) Order 2018 (legislation.gov.uk)
- Housing Act 2004, section 55 (legislation.gov.uk)
- Housing Act 2004, sections 65, 67, 72 and 249A (legislation.gov.uk)
- Housing Act 2004, Schedule 4 (legislation.gov.uk)
- Housing and Planning Act 2016, section 40: rent repayment orders (legislation.gov.uk)
- Housing Health and Safety Rating System (England) Regulations 2005, Schedule 1 (legislation.gov.uk)
- Shared house (HMO) licence (GOV.UK)
- Housing health and safety rating system: guidance for landlords (GOV.UK)
- When is planning permission required? (GOV.UK)
Last checked: 10 October 2026. This guide is general information, not legal advice.