Section 35(d) in Assam Notified Urban Areas (Other than Guwahati) Building Rules, 2014
(d)Whenever the dampness of site or the nature of the soil renders such precaution necessary the ground surface of the site between the walls of any building erected thereon shall be covered with a layer of sound cement concrete not less than 150 mm thick or with asphalt paving on a layer of sound cement concrete not less than 150mm thick or with asphalt paving on a layer of closely packed broken stone hard cake not less than 1 50mm thick or otherwise rendered damp proof to the satisfaction of the Authority.
