AUTHORITY OF BOARD.

(a) The board of adjustment may:

(1) hear and decide an appeal that alleges error in an order, requirement, decision, or determination made by an administrative official in the enforcement of this subchapter or a zoning regulation;

(2) hear and decide special exceptions to the terms of a zoning regulation when the regulation requires the board to do so; and

(3) authorize in specific cases a variance from the terms of a zoning regulation if the variance is not contrary to the public interest and, due to special conditions, a literal enforcement of the regulation would result in unnecessary hardship, and so that the spirit of the regulation is observed and substantial justice is done.

(b) In exercising its authority under Subsection (a)(1), the board may reverse or affirm, in whole or in part, or modify the administrative official's order, requirement, decision, or determination from which an appeal is taken and make the correct order, requirement, decision, or determination, and for that purpose the board has the same authority as the administrative official.

(c) The concurring vote of four members of the board is necessary to:

(1) reverse an order, requirement, decision, or determination of an administrative official;

(2) decide in favor of an applicant on a matter on which the board is required to pass under a zoning regulation; or

(3) authorize a variation in a zoning regulation.