Interpretation of Class C
C.3. For the purposes of paragraph C.1(b)—
(a)in the determination of the height of the highest part of the original roof, no account is to be taken of any relevant structure projecting from that roof;
(b)in the determination of the height of the highest part of the alteration, account is to be taken of any relevant structure comprised in the alteration; and
(c)“relevant structure” means any parapet wall, firewall, chimney or other roof furniture or similar structure.