Doors, Windows, and Glazing
Openings and hardware
Hollow metal frames, flush wood doors, and aluminum storefront are the common assemblies. Hardware functions follow BHMA grades, and closers, exit devices, and latching must satisfy the door schedule. Fire-rated openings follow NFPA 80: labeled frames and doors, closers, positive latching, and no field modifications to a labeled product.
Egress and accessibility
Egress doors are side-hinged, provide the required clear width, swing in the direction of egress in high-occupancy rooms, and carry panic hardware where the code occupant-load trigger is met. Accessibility standards set maximum thresholds (1/2 inch, or 3/4 inch if beveled), operable hardware, opening force, and closing speed.
Glazing
Safety glazing per CPSC 16 CFR 1201 is required in hazardous locations: in and beside doors, near tubs and showers, and in large panes close to the floor. Insulated glass units carry NFRC performance ratings for U-factor and solar heat gain, and correct setting blocks, sealants, and weep systems keep them performing.
Traps
Treating egress requirements and accessibility clearances as the same number; undercutting a rated door like a standard door; mixing up U-factor and SHGC; and forgetting that thresholds and hardware are part of the accessible route.
Rule of thumb: a 36-inch door leaf in a standard frame yields roughly 32 to 33 inches of clear width.