The setback requirements in Table VIII.3. above are for newly-developed thoroughfares. For highly built-up urban areas with duly established lines and grades reflecting therein proposed road widening and elevation, the requirements in Table VIII.3. above may not be imposed and the face of the building may abut on the side and/or rear property lines provided that all the requirements on open space, window opening, artificial ventilation, if any, and firewalls (Rule VII) are first fully complied with.