9(1)If the house forms part only of a hereditament, the gross value of the house is such proportion of the gross value shown in the valuation list for that hereditament as may be agreed in writing between the local housing authority and the person claiming compensation.
(2)If any dispute arises under sub-paragraph (1), the authority or the person claiming compensation may by means of a reference in writing submit the dispute for decision by the district valuer.