If the land shown on the official map is not yielding a fair return, the board of adjustment shall have the power to grant a permit for the building which will, as little as practicable, increase the cost of future acquisition, and the board may impose reasonable requirements as a condition of granting such permits. Such a permit shall not be granted when the applicant will not be substantially damaged by placing his building outside the boundary lines of the proposed facility.
KRS 100.307