Section 43(1) in The Haryana New Mandi Townships Building Rules, 1967
(1)Every cross-wall built of bricks or blocks laid in horizontal beds or courses which in pursuance of these rules may act as a return wall or party wall of a building, shall, except where it forms a part of a chimney constructed in accordance with the rule relating to chimneys and subject to sub-rules (2) and (3) of Rule 41, be of a thickness of at least two-thirds of that prescribed in Rules 41 and 42 for a structural or an external or a party wall of the same height and length and belonging to the same category of building, but shall not be less than 22.86 centimetres (nine inches) thick.
