Section 15

In cases of property assessed as described in section 17 where any house or building shall have been vacant for 30 consecutive days during any year, the Board shall remit so much of the rate for that year as may be proportionate to the number of days during which the said house or building may have remained unoccupied:

Provided that the owner of such house or building or his agent shall have given notice in writing of the vacancy thereof to the Board, and that the amount of rate to be remitted shall be calculated from the date of the delivery of such notice.