665. The purpose of the letting.

The dwelling house must be let as a dwelling for there to be a protected tenancy1. This is a different question from that of whether the premises are a dwelling house2. In determining whether premises are let as a dwelling, the following propositions apply3:

  1.  

    (1)     where the terms of a tenancy agreement provide for or contemplate the use of the premises for some particular purpose, then, subject to the qualification in head (2) below, that purpose is the essential factor in deciding the question whether or not the house can be said to have been let 'as a separate dwelling house' so as to fall within the Rent Acts4;

  2.  

    (2)     nevertheless, where t