The Wales Act 2017 changed the devolution model in Wales to that of a ‘reserved powers’ model. This allows the National Assembly to legislate on any subject except those specifically reserved to UK Government. Housing remains devolved to Wales by virtue of the fact that it is not ‘reserved’ to UK Parliament.
Broadly speaking, the National Assembly may legislate in all areas on the subject of housing. The Wales Act 2017 inserts a new section 108A into the Government of Wales Act 2006 and this section sets out a test to determine whether the National Assembly has ‘competence’ in a particular area it is proposing to legislate.Although the National Assembly’s power to legislate in this area is very wide, the UK Parliament continues to be able to pass laws for Wales relating to housing, subject to it obtaining the National Assembly's consent.
The Welsh Ministers have a number of executive functions in this area.