Large HMOs of seven or more: sui generis applications

Seven sharers takes a property outside Class C4 and into sui generis, which means planning permission is always required. There is no permitted change from C3 or C4 to a large house in multiple occupation, no prior approval route, and no Article 4 question to check. The only question is whether the council will grant permission, and that is decided on the local plan, the amenity of the building and the effect on the street.

Landlords who have moved a house from four beds to six without an application often assume the seventh is the same exercise. It is not. It is a full application with a fee, publicity, neighbour consultation and a real chance of refusal.

Where the sui generis line falls

Class C4 covers three to six people who do not form a single household sharing basic amenities. Class C3 covers households as defined in housing legislation, and both C3(b) and C3(c) cap at six residents. Once the seventh occupier is added, none of those classes fit, and the use sits outside the Use Classes Order entirely.

The count is of occupiers, not of bedrooms. A seven bedroom house let to six people is C4. A six bedroom house where two rooms are let as doubles to seven people is sui generis. Marketing material and tenancy agreements are what an enforcement officer reads, so the paper trail matters more than the floor plan.

Purpose built shared living, sometimes called co-living, is also sui generis, and in London it is dealt with under its own policy rather than as a large HMO. Outside London, treat it as a large HMO unless the local plan says otherwise.

What the application has to include

Assemble the submission around the questions the officer will ask, in the order the policy asks them.

• Existing and proposed floor plans with every room labelled and dimensioned, and a schedule giving the floor area of each bedroom and each communal room.
• A plan showing refuse and recycling storage, cycle storage, and how bins get from the store to the collection point.
• A planning statement addressing the concentration policy, amenity standards, parking and neighbour impact against the adopted policy numbers.
• A management statement naming the manager, the contact arrangements, the inspection frequency and how antisocial behaviour is dealt with.
• Parking evidence, which on a street under pressure means a survey rather than an assertion.

The management statement earns its place. Objections to large HMOs are usually about behaviour rather than about the building, and a credible management regime, offered as something the council can condition, addresses that directly.

Amenity standards inside the building

Councils apply two overlapping sets of standards, and the stricter one wins.

Licensing sets minimum sleeping room floor areas through the mandatory licence conditions: 6.51 m² for one person aged over 10, 10.22 m² where two people over 10 share, and 4.64 m² for a child under 10, with rooms below 4.64 m² unusable for sleeping. Many authorities apply higher figures through their own licensing standards.

Planning policy then adds communal space, kitchen capacity, bathroom provision and outdoor amenity space, usually expressed per occupier and set out in a supplementary planning document. Read the document rather than guessing, because the figures vary widely between authorities.

Three design decisions carry most of the weight at seven occupiers and above.

Keep a communal living room in addition to the kitchen. Converting the last reception room into a bedroom is the change that turns a defensible scheme into a refusal, and it is the first thing a case officer looks for on the plans.

Size the kitchen for the number of occupiers, with the cooking, storage and washing provision the licensing standards require, rather than assuming a family kitchen will do.

Provide bathroom facilities at the ratio the council's standards set, and show them on the plan rather than describing them in text.

Parking, bins and the street

These two topics decide more large HMO applications than anything internal.

On parking, the honest position is that occupancy rises and car ownership may or may not follow. Where the street is already saturated, a parking survey carried out to a recognised methodology, on the correct nights and outside holiday periods, is the only evidence that moves a highway officer. Where the site is well connected, say so with distances to the station and bus stops and a short transport statement rather than a general claim about sustainable location.

On refuse, do the arithmetic. Work out the weekly volume for the number of occupiers at the council's own collection frequency, size the store to hold it, and show the store in a position that does not put wheelie bins across the front garden. A waste management strategy covering storage, segregation and collection is worth preparing for anything above about six occupiers, because bins in the front garden are the visible sign neighbours point to.

Cycle storage is the easy win and the one most often forgotten. Secure, covered, at ground level, and accessible without carrying a bicycle through the kitchen.

Fire safety and licensing in parallel

Planning is one of three consents and the other two do not wait.

Mandatory HMO licensing applies to properties occupied by five or more people forming two or more households, so a seven bed HMO needs a licence whatever the planning position. Licensing conditions cover room sizes, amenities, management and safety, and the housing team will inspect.

Building control comes next. Adding occupants to a house is a material change of use for Building Regulations purposes, bringing fire separation, protected escape routes, alarm systems and, in some layouts, sprinklers, along with sound insulation between rooms in separate occupation. Fire safety guidance for existing housing is what enforcement teams use, and it is more demanding on a larger HMO with a longer escape route.

Illustrative example: an investor applies to convert a six bed C4 property to eight bedrooms. Room sizes all exceed the licensing minimums, the parking survey shows spare capacity, and the bin store is drawn. The application is refused because the council's supplementary planning document requires a communal living room in addition to a dining kitchen and the scheme has none. Restoring the living room and losing one bedroom would have made it approvable.

Refusal reasons and how to answer them

The recurring grounds are concentration, amenity, parking and character. Each has a specific answer.

For concentration, map the HMOs within the radius the policy uses, using the council's own licensing register, and present the calculation rather than leaving the officer to do it. If the property already sits above the threshold, the honest options are a smaller scheme or a different property.

For amenity, present the room schedule against the policy figures line by line, and state where the scheme exceeds them.

For parking, produce survey data. For character, address bin storage, front garden treatment, boundary walls and the appearance of the frontage, since character objections are usually about what the street sees.

Where permission is refused, an appeal to the Planning Inspectorate is available within six months. Inspectors expect concentration policies to be applied on evidence, so a refusal that asserts over-concentration without a calculation is worth testing.

This is general guidance rather than legal advice. Check the position with your local planning authority or a qualified professional before relying on it.

Enter your postcode on PlanScope to see which supporting documents a large HMO application is likely to need. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.