How to Build Your Commercial Opening
DETERMINE YOUR OPENING CONDITIONS
Fire Ratings and Application
The first step in filling your commercial opening is to determine the opening condition. What is your wall condition (this will determine fire ratings for exterior, interior, corridor, etc.)? What is your wall construction (steel stud, wood stud, block)? What is your rough opening to determine your door and frame sizes? The answers to these questions will lead you to selecting your commercial door and frame.
Fire doors and their respective frames and hardware are rated by the amount of time, in minutes or hours, that a door can withstand the heat and pressure of a fire in test conditions. Laws and regulations can vary greatly between states, cities, townships and municipalities. We recommend that you check with all regulating authorities to ensure the door units you order and install comply with all applicable laws.
Positive Pressure (UL 10c) Fire Doors
The WDMA (Window and Door Manufacturers Association) separates positive pressure fire-rated doors into two categories. Both Category “A” and Category “B” doors make use of intumescent seals. These materials expand when heated, creating a tight seal and filling in gaps around the door. This expansion helps prevent the spread of fire and super-heated gasses from escaping the opening.
Category “A”- Wood Doors
Category “A” doors have intumescent seals and/or gasketing built into the structure of the door. Although typically they do not require additional sealing between the door and frame in some cases they may require a smoke seal or additional gaskets.
Category “B”- Wood or Hollow Metal Doors
Category “B” doors are neutral pressure doors that require an additional intumescent strip and/or gasket kit applied to the frame to provide an intumescent seal. Because fire regulations can vary greatly, some areas will also require an intumescent strip as part of the door’s edge. Please discuss your needs with your BWI Commercial Representative and we will be happy to add these additonal gaskets and or intumescent strips to your order. They can be applied according to the enclosed instructions by the installer in the field.
Smoke Seal Labels
Some doors, regardless of pressure requirements, may also require a smoke seal (‘’S”) label. This label indicates that the installer is required to apply a category “H” gasket to the frame. If you are in need of a (“S”) label let your BWI Commercial representative know and we’ll get you what you need.
Fire doors must self-close and latch. This is accomplished using a door closer or self-closing hinges. Not a problem, we’ve got you covered. See page 8 and 9 for our hardware offerings.
Fire doors must have a labeled automatic latching device to engage the strike. Locksets with a latch bolt or a panic device with a latch bolt are required. Deadbolts can’t be used in place of a latch bolt, but can be used to add additional security to an opening with a latch bolt, except on egress doors.
Door Unit vs Wall Fire Ratings
Commercial codes typically require that door units be rated for three-fourths of the rating of the surrounding wall. So if you have a 4 hour rated wall use a 3 hour rated door; a 2 hour rated wall use a 90 minute rated door; and a 1 hour rated wall use a 45 minute rated door.
Adding a Lite to a Fire-Rated Door
Vision lites can be added to fire doors provided certain requirements are met. The cutout must be done in an authorized labeling shop. The products used i.e. glass, lite kit and glazing material are all approved fire rated products. The size limitations of a lite is determined by the hourly rating and glass type used.