1204.2 Natural Light
For the purpose of natural lighting, any room is permitted to be considered as a portion of an adjoining room where one-half of the area of the common wall is open and unobstructed and provides an opening of not less than one-tenth of the floor area of the interior room or 25 square feet (2.32 m2), whichever is greater.
Exception: Openings required for natural light shall be permitted to open into a sunroom with thermal isolation or a patio cover where the common wall provides a glazed area of not less than one-tenth of the floor area of the interior room or 20 square feet (1.86 m2), whichever is greater.
Exterior openings required by Section 1204.2 for natural light shall open directly onto a public way, yard or court, as set forth in Section 1205.
Exceptions:
Required exterior openings are permitted to open into a roofed porch where the porch meets all of the following criteria:
- 1.1. Abuts a public way, yard or court.
- 1.2. Has a ceiling height of not less than 7 feet (2134 mm).
- 1.3. Has a longer side at least 65 percent open and unobstructed.
- Skylights are not required to open directly onto a public way, yard or court.