There are minimum space standards that apply depending on the number of people who occupy the property.
It would be surprising if, as a responsible landlord, you were not able to meet these minimum standards.
In a property for a single person there must be a minimum surface area of 9m² and ceiling height 2.20m², or total volume of 20m², with minimum ceiling height of 1.80m.
The surface area increases to 16m² for two persons and 9m² for each additional person.