Householder rights at a house in multiple occupation

Whether hmo permitted development rights exist at all turns on one word in the General Permitted Development Order 2015. Part 1 grants rights to a dwellinghouse, and the Order defines that term only by excluding a building containing one or more flats and a flat within such a building. It says nothing about multiple occupation. So a small house in multiple occupation in Class C4 keeps the physical and functional character of a house, and most authorities treat Part 1 as available to it. A large house in multiple occupation in sui generis use is far less certain, and that is where the arguments happen.

Is a house in multiple occupation a dwellinghouse

The honest answer is that it depends on the building and the authority, and that no provision of the Order settles it.

The argument for availability is textual. The exclusion in the Order is aimed squarely at flats, and a terraced house let to five sharers is still a house: one front door, shared kitchen and living space, no self-contained units. On that reading Part 1 applies and the usual Class A and Class E limits do the work.

The argument against is functional. A dwellinghouse has been described in the courts as a building providing the facilities for day-to-day private domestic existence, and an authority can say that a property occupied by several separate households is not used as a single dwelling at all. That argument gets stronger as the property gets further from a house in use: bedroom locks, en suites in every room, a cluster of bins, no shared living room.

Where a scheme depends on the answer, the only sensible route is a Lawful Development Certificate under section 192 of the Town and Country Planning Act 1990 for the proposed works. It is the only formal way lawfulness is confirmed, and the supporting planning statement should set out the class relied on, each limit, and why the property is a dwellinghouse. Budget for a refusal and a planning application if the authority takes the functional view.

Class C3, Class C4 and the line above it

Class C3 covers dwellinghouses, including occupation by a single person or household and by small groups living together as a single household. Class C4 covers a house in multiple occupation shared by between three and six unrelated residents who share basic amenities. Above six residents the use falls outside the classes and is sui generis.

Class L of Part 3 of Schedule 2 permits change of use between Class C3 and Class C4 in both directions. That right is what makes small HMO conversion straightforward in most of the country, and it is the right authorities remove.

Going above six residents always needs a planning application. It is a change to a sui generis use, there is no permitted development route, and the application will be assessed on amenity, parking, bin and cycle storage and the concentration of similar uses nearby. The physical works that usually accompany it, an additional bedroom in a loft or a rear extension, are a separate question from the use.

Article 4 directions

In towns with concentrated student or shared housing markets, authorities routinely make Article 4 directions withdrawing the Class L right to change from C3 to C4 in a defined area. The effect is that a small HMO needs planning permission there, assessed against the authority's HMO policy.

Those policies commonly work on concentration. A limit expressed as a proportion of properties in multiple occupation within a stated radius of the application property, a restriction on a new HMO adjoining an existing one, and sometimes a threshold measured along a street frontage. The figures and radii differ between authorities, so get the policy and the authority's own evidence base rather than working from what a neighbouring council does.

Check the direction itself, not a map layer. Directions are made for specific areas and specific classes, and the boundary rarely follows a ward.

Extensions and outbuildings in practice

Assume for a moment that Part 1 is available. The limits apply exactly as they would to a family house, with no concession for the number of occupants.

Rear extensions are measured against the depth, height and eaves limits for the house type, with the tighter position on article 2(3) land. Side extensions are restricted to half the width of the original house and one storey. Roof enlargements under Class B carry the volume allowance and the side-elevation obscure glazing condition. Outbuildings under Class E are limited by the 50 per cent curtilage rule, which is where larger shared properties with converted garden buildings run into trouble, as the 50 per cent curtilage rule for garden outbuildings explains.

One trap is specific to shared housing. An outbuilding used as an additional bedroom with its own facilities can create a separate planning unit, taking it outside the incidental use that Class E permits and creating an unauthorised dwelling. The same analysis applies to garden offices and the separate planning unit problem.

Bin and cycle stores

Small, and the reason more HMO applications are refused than any design issue.

A property with six residents generates more waste than the frontage was designed for, and a row of bins in a front garden is both a visual harm and a public health complaint. Class E does not permit an outbuilding or enclosure forward of a wall forming the principal elevation, so a front bin store generally needs permission.

What gets approved is a purpose-built enclosure of a stated capacity, screened, with doors that open clear of the footway, matched to the collection cycle and the number of bins the waste authority will supply. Show the bin numbers and sizes on the plan and say which day they are collected. Cycle parking is usually required at a ratio set in the local plan, in a secure and covered store rather than a rack in the garden.

Amenity space and parking

HMO policies typically set a minimum area of private or shared external amenity space, a requirement for a communal living room in addition to bedrooms, and a parking standard based on residents rather than bedrooms.

Parking is the contested one. Where the street is already stressed, a Parking Survey carried out on a recognised beat methodology, overnight midweek and at a weekend, outside school holidays, is the evidence that answers the highway officer. Asserting that sharers do not own cars does not.

Where a property sits in a controlled parking zone, expect the authority to seek an agreement limiting resident permits, and factor that into the letting proposition rather than discovering it later.

Licensing runs alongside, and does not replace planning

These are separate regimes with separate triggers and neither consent implies the other.

Mandatory licensing under the Housing Act 2004 applies to properties occupied by five or more people forming two or more households, and many authorities operate additional licensing schemes covering smaller HMOs. Licence conditions include minimum sleeping room sizes, set by regulations made in 2018 at 6.51 m² for one adult and 10.22 m² for two sharing, with a smaller figure for a child under ten. Verify the current figures, since they are set by regulation and can change.

A licence does not establish that the use is lawful in planning terms, and a planning permission does not satisfy the licensing authority. Fire safety, means of escape and the hazard rating of the property run under housing and fire legislation independently of both. Applicants who treat the licence as evidence of planning lawfulness find out otherwise when they sell.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. Enter your postcode on PlanScope to see which documents an HMO application at your address would need.