Streets of 50-foot width shall be divided into a roadway area of 30 feet with a sidewalk area on each side of 10 feet. The sidewalk area shall be graded to an elevation of two inches above the finished center-line grade. Off-street parking shall be provided for the use of any owners fronting on streets having a 30-foot roadway area. Whenever the roadway area of any street is planned and constructed to be 34 feet with sidewalk area on each side of eight feet, then parking along any such street shall be permitted, subject, however to the ordinance power of the Borough with respect to the regulation of parking, which power may be exercised at any time notwithstanding this provision or any interference that might be otherwise drawn here from.