There shall be only one principal building and principal use
per lot in R1 Districts.
The height limitations of this chapter, as shown in Table 2, shall not apply to the following structures: church spires;
belfries; silos; cupolas; domes not used for human occupancy; chimneys;
ventilators; skylights; water tanks; bulkheads and other necessary
mechanical appurtenances usually carried above the roof level, parapet
wall or cornice for ornament extending above such height limit not
more than five feet; radio or television receiving antenna; or a public
utility transmission tower or cable. No such uses shall in their aggregate
coverage occupy more than 20% of the roof area on which located.