What is the minimum size for a single bedroom in the UK?

Under the Nationally Described Space Standard (NDSS), a single bedroom must be at least 7.5 m² with a minimum dimension of 2.15 m. Under the Housing Act 1985 room standard, a room under 4.65 m² (50 sq ft) cannot be used as a sleeping room at all. Rooms between 4.65-6.5 m² can only accommodate 0.5 of a person (a child under 10).

What is the minimum size for a double bedroom?

The NDSS requires a double bedroom to be at least 11.5 m² with a minimum dimension of 2.75 m. This allows space for a double bed (1350 x 1900 mm), bedside tables, a wardrobe and a desk or dressing table. Under the Housing Act 1985, a room must be at least 10.2 m² (110 sq ft) to count for 2 persons.

Is the NDSS mandatory?

The NDSS is not automatically mandatory. It is a nationally recognised standard that local planning authorities can choose to adopt through their local plan policies. Once adopted locally, it becomes a condition of planning permission for new dwellings. Many London boroughs and major cities have adopted NDSS. Check with your local planning authority to see if it applies in your area.

What are the Housing Act 1985 overcrowding standards?

The Housing Act 1985 sets two overcrowding standards. The Room Standard: two persons of opposite sex aged 10+ should not have to share a sleeping room (unless a couple). The Space Standard: rooms under 4.65 m² count for 0 persons, 4.65-6.5 m² for 0.5 person, 6.5-10.2 m² for 1 person, and over 10.2 m² for 2 persons. Children under 10 count as 0.5 person.

What is Part M and how does it affect room sizes?

Part M of the Building Regulations covers access and facilities for disabled people. Category 1 (M4(1)) applies to all new dwellings and requires level approach and step-free entrance. Category 2 (M4(2)) is optional and requires wider corridors (1200 mm), 1500 mm turning circles, and step-free access throughout. Category 3 (M4(3)) is wheelchair accessible with even larger room dimensions.

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Minimum Room Size Calculator — NDSS and Housing Act Standards

Check whether your room sizes meet the Nationally Described Space Standard (NDSS) and Housing Act 1985 overcrowding standards. Covers bedrooms, living rooms, kitchens and bathrooms.

Room Type

Select the type of room to check

Number of Occupants

Number of people using the dwelling

How We Calculate This

This calculator uses the Nationally Described Space Standard (NDSS) published by the Ministry of Housing, Communities and Local Government (MHCLG) and the Housing Act 1985 overcrowding standards to determine minimum room sizes.

NDSS Minimum Areas

Single bedroom: 7.5 m² (min 2.15 m wide)
Double bedroom: 11.5 m² (min 2.75 m wide)
Living room: 13-23 m² depending on occupancy
Separate kitchen: ~8 m²
Kitchen-diner: ~11-15 m²
Bathroom: ~3.7 m²

Housing Act 1985 Space Standard

<4.65 m² (50 sq ft): cannot be used as sleeping room
4.65-6.5 m²: 0.5 person (child under 10)
6.5-10.2 m²: 1 person
>10.2 m² (110 sq ft): 2 persons

References

Nationally Described Space Standard (MHCLG, March 2015)
Housing Act 1985, Part X — Overcrowding
Approved Document M — Access to and use of buildings

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Last updated: February 2026

All calculations are estimates. Verify with your supplier.