16.—(1) This regulation applies to buildings with a total useful floor area over 1,000m2 occupied by public authorities and by institutions providing public services to a large number of persons and therefore frequently visited by those persons.
(2) Except where regulation 18(3) applies, on and after 6 April 2008 every occupier of any building to which this regulation applies must—
(a)have in its possession or control at all times a valid advisory report; and
(b)display at all times a valid display energy certificate in a prominent place clearly visible to the public.
(3) A display energy certificate is valid for a period of 12 months beginning with the nominated date.
(4) An advisory report is valid for a period of seven years beginning with the date it is issued.