(a) The Board shall hear requests for variances where it is alleged that the provisions of this chapter inflict unnecessary hardship upon the applicant. The Board may by rule prescribe the form of application and may require preliminary application to the Zoning Officer. The Board may grant a variance, provided that all of the following findings are made where relevant in a given case:

[1] That there are unique physical circumstances or conditions, including irregularity, narrowness, or shallowness of lot size or shape, or exceptional topographical or other physical conditions peculiar to the particular property and that the unnecessary hardship is due to such conditions and not the circumstances or conditions generally created by the provisions of this chapter in the neighborhood or district in which the property is located.
[2] That because of such physical circumstances or conditions, there is no possibility that the property can be developed in strict conformity with the provisions of this chapter and that the authorization of a variance is therefore necessary to enable the reasonable use of the property.
[3] That such unnecessary hardship has not been created by the appellant.
[4] That the variance, if authorized, will not alter the essential character of the neighborhood or district in which the property is located, nor substantially or permanently impair the appropriate use or development of adjacent property, nor be detrimental to the public welfare.
[5] That the variance, if authorized, will represent the minimum variance that will afford relief and will represent the least modification possible of the regulation in issue.

(b) In granting any variance, the Board may attach such reasonable conditions and safeguards as it may deem necessary to implement the purposes of the Pennsylvania Municipalities Planning Code and this chapter.

Expiration of special exceptions and variances.
Unless otherwise specified by the Board, a special exception or variance shall expire if the applicant fails to obtain a building permit within one year of the date of the granting of the special exception or variance. If the special exception or variance requires a subdivision or land development, the special exception or variance shall expire if the applicant fails to file an application for preliminary subdivision or land development within two years of the date of the granting of the special exception or variance.