International Building Code Section 501


International Building Code 501.1

Scope. The provisions of this chapter control the height
and area of structures hereafter erected and additions to existing
structures.

International Building Code 501.2

Address numbers. Buildings shall have approved
address numbers, building numbers or approved building identification
placed in a position that is plainly legible and visible
from the street or road fronting the property. These numbers
shall contrast with their background. Address numbers shall be
Arabic numerals or alphabetical letters. Numbers shall be a
minimum of 4 inches (102 mm) high with a minimum stroke
width of 0.5 inch (12.7 mm).