A. General:
1. Install windows in outside walls to provide natural light and ventilation in all habitable rooms.
2. Windows in habitable rooms, whose areas provide the light and ventilation necessary to comply with the following requirements, are considered required windows. All windows in addition to these, and also windows in rooms other than habitable rooms, are considered nonrequired windows.
3. The area of glazed portions of doors located in exterior walls may be included when necessary in determining compliance with the following requirements.
4. Where window or drain openings are provided below grade, protect with metal gratings.
B. Habitable Rooms: A habitable room is a room designed to be used for living, sleeping, eating or cooking. Required windows in each habitable room as follows:
1. Total Glass Area: Not less than ten percent (10%) of floor area of room.
2. Ventilating Area: Not less than five percent (5%) of floor area of room.
C. Alcoves: An alcove is a recess connected or at the side of a larger room.
1. Unless separately lighted and ventilated by windows which provide the required window area, include any alcove adjoining a habitable room as part of that room in computing required window area.
2. The common wall between the alcove and the habitable room shall contain an opening, the area of which shall not be less than eighty percent (80%) of the area of the entire wall on the alcove side.
D. Bathrooms and Water Closet Compartments: Provide ventilation by one of the following means:
1. Windows or Skylight: Windows or skylights located in exterior walls or roofs the light and vent area will not be less than three (3) square feet.
2. Vent in or near ceiling with continuous duct connection to outside air.
a. Gravity exhaust, connect to louvered roof vent, minimum duct dimension, three and one-half inches (31/2"); minimum area, forty eight (48) square inches.
b. Mechanical exhaust, one complete air change each ten (10) minutes.
E. Open Basements: Provide light and ventilation by windows or doors in exterior walls with both glazed and ventilating area not less than two percent (2%) of the floor area.
F. Utility Rooms: A utility room is a room or area, enclosed or unenclosed, that the major housekeeping appliances, laundry facilities and water heating devices are located. Ventilate utility room by:
1. Windows or doors in exterior walls with ventilating area not less than five percent (5%) of floor area; or
2. Duct or ducts to outside area minimum total free area two percent (2%) of floor area.
G. Heater Rooms: A heater room is an enclosed room or area where the central heat producing device is located. Provide fixed ventilation to any confined space which encloses heating equipment by means of ducts arranged to supply continuous circulating air from outside. Ducts to be screened and to have total free area equal to one square inch for each one thousand (1,000) B.T.U. input rating of all fuel burning equipment.
H. Crawl Spaces: A crawlspace is an area beneath the bottom of floor joists and the ground below.
1. Unheated crawlspaces, install at least four (4) foundation wall vents located near corners of the crawlspaces having a free ventilating area equal to 1/160 of the ground area of the crawlspace in square feet.
2. Heated crawl spaces, install at least two (2) foundation wall vents located for effective cross ventilation having a free ventilating area equal to 1/1200 of the ground area of crawlspace in square feet.
3. No vents required for basementless spaces one side of which, exclusive of structural supports such as piers, chimney foundations, etc., is open to a ventilated basement, provided the total area of ventilating openings is two percent (2%) of the sum of the basement area and the area of the basementless space.
4. In each vent opening, install corrosion-resistant screening, mesh not less than eight (8) per inch.
5. In crawlspaces, ground shall be covered with four inches (4") of coarse granular material one-half inch (1/2") to five- eighths inch (5/8") reasonably level over which a vapor smooth asphalt roofing weighing at least fifty five (55) pounds per one hundred eight (108) square feet, (or material of equal Perm rating) lapped four inches (4"). Extend up foundation wall six inches (6").
I. Attics and Air Space Between Ceiling and Flat Roofs: Attic means the space between the ceiling beams of the top habitable story and the roof rafters.
1. Provide effective fixed ventilation in all spaces between roofs and top floor ceilings by replaceable or nonferrous screened louvers, sixteen (16) mesh.
2. Net ventilation area for each separate space to be not less than 1/300 of area of house at top plate. Where possible, locate vents to provide effective cross- ventilation. (Ord. 0-71-12, 3-11-71)