I often get asked by Clients, "how do we maximize glazed window openings in rated corridor walls?" The rule in the Building Code is that up to 25 percent of the area of the common wall, shared by the corridor and adjoining room, may contain 20-minute fire-protection-rated window assemblies.
For example, if the common wall of the corridor was 100 square feet, 25 square feet of the corridor common wall may contain 20-minute fire-protection-rated window assemblies in addition to any 20-minute rated fire door located in the same wall.
To avoid the 25 percent window area limitation and maximize transparency in the corridor walls, 1-hour fire-resistance-rated glazing assemblies tested in accordance with ASTM E119 or UL 263 may be used.
Some companies that manufacture and supply fire-resistance-rated glass window and door assemblies include:
