From 25 February 2016, a new House in Multiple Occupation (HMO) class will be added into the use classes for planning permission purposes which will have serious consequences on landlords who wish to change to HMOs in Wales.

What are use classes?

Under the Town and Country Planning (Use Classes) Order 1987 several classes of use are defined for which planning permission needs to be obtained. If a use is not mentioned in the order they are know as a ’Sui Generis’ use. Examples are theatres, car showrooms and filling stations. A Sui Generis use still requires planning permission but is likely to be more specific than the generally more broad definitions contained in specific use classes.

A normal dwelling in Wales will currently be known as a “class C3 Dwellinghouse” which is a use for up to six people occupying as a single household only. Arguably some HMOs may need planning permission before the change because they won’t be being occupied as a single household or may have more than seven people residing. However, it was little enforced and in order for planning of this type to be needed (before change), there would need to be “… the making of any material change in the use of any buildings or other land …”. The question of what a “material” change in use is a difficult one.

The new classes

From 25 February 2015, Class C3 is slightly amended and a new class C4 is introduced. This brings the classes into line with England where C3 was changed and C4 has existed for a number of years.

Class C3 in Wales is amended to say:

Class C3. Dwellinghouses

Use as a dwellinghouse (whether or not as a sole or main residence) by—

(a) a single person or by people to be regarded as forming a single household;

(b) not more than six residents living together as a single household where care is provided for residents; or

(c) not more than six residents living together as a single household where no care is provided to residents (other than a use within class C4).

Interpretation of Class C3

For the purposes of Class C3(a) “single household” is to be construed in accordance with section 258 of the Housing Act 2004(2)

The new class C4 introduced says:

Class C4. Houses in multiple occupation

Use of a dwellinghouse by not more than six residents as a house in multiple occupation.

Interpretation of Class C4

For the purposes of Class C4 a “house in multiple occupation” does not include a converted block of flats to which section 257 of the Housing Act 2004 applies but otherwise has the same meaning as in section 254 of the Housing Act 2004.

This has the effect that from 25 February 2015 any new change of use from a single household letting to a house in multiple occupation with 3 or more unrelated sharers would first need planning permission.

The change will also affect taking 3 or more lodgers as they too would make a property an HMO and require planning permission.

Permitted Development

In England, there is a permitted development to go from C3 to C4 without the need for planning. It is also a permitted development to go back from C4 to C3.

Wales has chosen to only allow the latter. Therefore, also from the 25 February 2015, it will be a permitted development (planning permission not necessary) to change the use from a C4 class (HMO) to a single household letting (C3). It will not be permitted to go back again though without planning permission first being sought.

This in our view is an utterly crazy decision and it is respectfully submitted Wales should have followed England and allowed a permitted development both ways. The larger HMOs (seven or more people) would still be caught and require planning. England tried this way at first but soon changed it to allow a permitted development both ways.

An example of a problem with this new ruling can be quickly illustrated:

If currently there are two female sharers in a house who are just friends, the property is not an HMO because there needs to be 3 or more occupying1. If one of the two females has a baby, the property immediately becomes an HMO and planning permission would be required or, to avoid prosecution, the landlord would have no alternative but to evict!2

Existing HMOs

As discussed earlier, it may well have been the case that some HMOs ought to have obtained planning permission before the change regardless. In which case, the change simply strengthens the requirement.

However, as a general rule if there is an existing HMO on the 25 February, there is no “change in use” occurring (because it’s already being used for that purpose). However, as we say, it all depends whether that use was lawful in the first place under the previous rules.

A landlord wishing to be certain can apply for a “certificate of lawful use” where an established use has been used for some time3.


  1. Two sharers are exempt by schedule 14 Housing Act 2004 
  2. The reason it’s an HMO is because the two females are friends and so more than one household. If they were a couple “living together as married” and one had a child, the property would not be a HMO because all occupiers would be part of a single household. 
  3. The link is to England guidance as I couldn’t find a Wales version but they should be similar