Projection into required front or rear yard. An uncovered, unenclosed deck, porch, patio or paved terrace may project into a required front yard for a distance not exceeding 10 feet, or may project into a required rear yard for a distance not exceeding 20 feet, but not to exceed a distance equal to 60% of the depth of the rear yard; provided, however, that this shall not be interpreted to include or permit fixed canopies in a required front or rear yard.