Nothing in this chapter shall be construed to prevent the ordinary
maintenance and repair of any exterior architectural feature of a
landmark or property within an Historic Preservation Overlay District
that does not involve a change in design, material or outward appearance.
No person shall carry out any exterior alteration, restoration, reconstruction,
demolition, new construction, or moving of a landmark or property
within an Historic Preservation Overlay District, nor shall any person
make any material change in the appearance of such property, its windows
and shutters, exterior light fixtures, signs, sidewalks, fences, steps,
paving, changes in grade, or other exterior elements which affect
the appearance and cohesiveness of the landmark or Historic Preservation
Overlay District, without first obtaining a certificate of appropriateness
from the Historic Preservation Board.