There is a lot of housing case-law on what constitutes a house and what constitutes a household for HMO purposes. There have been a number of legal cases about whether the mode of living of particular groups of people sharing a house constitutes a single household or not.
Doubts remain over the application of the definition.
For example while courts have ruled that houses shared by students are not in multiple occupation, conversely the definition has been applied to premises such as religious conference centres. The Government believes that safe and properly managed HMOs have an important function in the private rented housing market. Many people need access to cheap flexible accommodation and in most areas HMOs meet this need. HMOs also have a particular role in providing affordable accommodation in areas of high housing demand where rents are high. Unfortunately both physical conditions and management standards are often worst in HMOs, and they can also pose the most significant fire risks to occupants.