(1) In sections 372X and 372Y -
'certificate of reasonable cost' means a certificate granted by the Minister for the Environment and Local Government for the purposes of section 372X or 372Y, as the case may be, stating that the amount specified in the certificate in relation to the cost of construction of the house to which the certificate relates appears to that Minister at the time of the granting of the certificate and on the basis of the information available to that Minister at that time to be reasonable, and section 18 of the Housing (Miscellaneous Provisions) Act, 1979, shall, with any necessary modifications, apply to a certificate of reasonable cost as if it were a certificate of reasonable value within the meaning of that section;
'house' includes any building or part of a building used or suitable for use as a dwelling and any outoffice, yard, garden or other land appurtenant to or usually enjoyed with that building or part of a building;
'total floor area' means the t