The Board may allow a variance only in cases involving practical difficulties or unnecessary hardship, when the record to the Board supports all of the following affirmative findings:

1. That the alleged hardship or practical difficulties, or both, are exceptional and peculiar to the property.
2. That the alleged hardship or practical difficulties, or both, which would result from a failure to grant the variance, include substantially more than inconvenience or inability to attain a higher financial return, or both.
3. That allowing the variance will result in substantial justice being done, considering the public benefits and the individual hardships that will be suffered by a failure of the Board to grant a variance.
4. That the conditions and circumstances, which are the bases of the variance request, shall not be self-imposed.

If a variance has been granted, and the construction authorized with the variance has not commenced within one year from the date of its approval, the grant of the variance shall be automatically withdrawn.

Each section, subsection, provision, requirement, regulation or restriction established by these rules for driveway permits or any amendments or additions thereto, is hereby declared to be independent, and the holding of any part to be unconstitutional, invalid or ineffective for any cause shall not affect nor render invalid the resolution or amendments or additions thereto as a whole or any other part thereof, except as to the particular part so declared to be invalid.