Every principal building shall be built upon a lot with frontage upon a public street improved to meet the borough requirements or for which such improvement has been guaranteed by the posting of a performance guarantee pursuant to this chapter unless relief has been granted under the provisions of N.J.S.A. 40:55D-36.

Where a building lot has frontage on a street, which the master plan or the official map of the borough indicates is proposed for right-of-way widening, the required front yard setback shall be measured from such proposed right-of-way line.