Section 257 HMOs: the converted block that catches freeholders

This is the HMO category almost nobody expects to be in, because the building does not look like an HMO to anyone. Every flat is self-contained. Every occupier has their own front door, kitchen and bathroom. Nothing is shared.

And the whole building can still be an HMO — with the duties falling on whoever owns the freehold or holds the head lease.

The test — section 257

A converted block of flats is a section 257 HMO where both:

1. the conversion did not comply with the Building Regulations 1991 (or later applicable standards) and still does not; and
2. less than two-thirds of the self-contained flats are owner-occupied.

Both limbs must be met. A pre-1991 conversion where four of six flats are owner-occupied is not caught — two-thirds are owner-occupied. Drop to three of six and it is.

Why the 1991 date does the work

The 1991 Building Regulations brought in the fire-separation standards for conversions that modern practice takes for granted — compartmentation between flats, protected escape routes, fire-resisting construction. A conversion done before that, or done after it without complying, produces a building where a fire in one flat threatens the others.

Section 257 exists to give councils a route into those buildings. It is a fire safety provision wearing a licensing hat, and reading it that way makes the rest of it make sense.

Who is liable

The person managing or person having control — in practice the freeholder or head lessee, not the individual flat owners or their tenants. This is the sting: a freeholder who has never let a room in their life, whose leaseholders all have their own ASTs with their own tenants, is the HMO landlord for the building.

Licensing

A section 257 HMO is not caught by mandatory licensing — the England order excludes purpose-built blocks and the mandatory route runs on the standard, flat and converted-building tests. But it can be caught by additional licensing where a council designates to include section 257 properties, and many do exactly that. Check the designation: this is precisely the case where "our building is not an HMO" and the designation disagree. See additional licensing and how to read a designation notice.

The management regulations that apply are different ones

Worth stating precisely, because using the wrong SI is a common error. Section 257 HMOs are governed by the Licensing and Management of Houses in Multiple Occupation (Additional Provisions) (England) Regulations 2007, not the 2006 management regulations that cover ordinary HMOs.

They impose duties over the common parts and the building’s shared systems rather than inside the flats: fire safety measures and escape routes, the structure and exterior, common installations, and providing the manager’s contact details to occupiers.

What a freeholder should actually do

1. Establish the conversion date and standard. Building control records, the deeds, the original planning file.
2. Count owner-occupation. It moves. A block that fell outside the test when three flats were owner-occupied falls inside it when one is sold to an investor, and nothing tells you.
3. Check the council’s additional licensing designation for whether section 257 properties are included.
4. Get a fire risk assessment for the common parts, which the 2007 Regulations effectively require you to act on.

England and Wales

Section 257 is in the Housing Act 2004 and applies in both. The management regulations for section 257 HMOs are made separately for each country, so cite the Welsh instrument for a Welsh building. See HMO licensing in Wales.

Information tool, not legal advice. Section 257 status turns on building history; take advice.