The cross ventilation option may be used if the following criteria have been met:
- Operable aperture areas totaling a minimum of 12 percent of the floor area of the room shall be provided for all primary living areas and main bedrooms.
- Insect screens shall be provided for all operable windows, skylights and doors to be considered operable aperture area. All screened entry doors and interior doors in the ventilated areas shall be provided with either (1) mechanically attached door stops (or similar devices) to hold the door in an open position or (2) operable louvers.
- The total aperture area shall be provided by a minimum of two distinct windows or one window and one skylight. Each operable unit shall provide not more than 70 percent of the total aperture area. The windows (or sliding glass doors) shall be placed in walls adjacent or opposite to each other. The windows may be placed on a single outside wall if a skylight or wing walls are used.
- Where wing walls are included in the building design for ventilation purposes, they shall be placed between windows to create a high-pressure and a low-pressure zone on each window. Wing walls shall extend from the ground to eave height, be located on the windward side of the building and extend outward from the building a distance at least equal to one-half the width of the window. NOTE: This technique is effective only for areas that experience significant and continuous winds during the cooling months.