fire door specifications

Sun Mountain is licensed to both manufacture and pre-hang fire-rated wood doors in a number of different species and panel configurations. 20-minute, 45-minute, 60-minute, and 90-minute fire ratings are all available to fit your particular construction project and code requirements. All of our fire-rated doors meet UL 10C/NFPA 252 for both positive pressure and negative pressure test requirements. In additiona, all of our fire-rated doors are Category “A”, meaning no additional edge-sealing system is required on the door jambs. All doors are eligible to bear the "S" (for Smoke & Draft Control assemblies) if a listed "Category H - Smoke & Draft Control Gasket" has been applied to the assembly. Both single swing or double swing pairs of doors are available. In addition, for all ratings except 90-minute, listed wood fire-rated jambs are available as well. 

20-Minute Rated Fire Doors

The maximum size available for a single door is 3/6 x 8/0, and 7/0 x 8/0 for a double door unit. 20-minute rated lited doors (doors with glass) are also available, using a special fire-rated clear glass, as long as the total glass size is less than 1296 square inches. Mortised manual and automatic flush bolts and automatic door bottoms are also available. 

20-minute fire-rated wood jambs are also available in most species. The jamb width must be at least 4-9/16”, and will also qualify for a positive pressure fire rating with hose stream. 

45-Minute Rated Fire Doors

The maximum size limit available for these doors is 3/6 x 8/0 for single swings, and 7/0 x 8/0 for double swings. Glazing is allowed up to 1248 square inches. Wood jambs are allowed on single swing units only, and must be at least 4-9/16” wide. Steel frames are available for double door applications. Mortised flush bolts are available; however, mortised auto door bottoms are not available. 

60-Minute Rated Fire Doors

The maximum size limit available for 60-minute rated fire doors is 3/6 x 8/0 for single swings, and 7/0 x 8/0 for double swings. Glazing is allowed up to 100 square inches. Wood jambs are allowed on single swing units only, and must be at least 4-9/16” wide. Steel frames are available for double door applications. Mortised flush bolts are available; however, mortised auto door bottoms are not available. 

90-Minute Rated Fire Doors

90-minute rated wood fire doors are available in sizes up to 3/6 x 8/0. Double door applications are not available. Glazing is allowed up to 100 square inches. All units must be hung in steel frames. Mortised flush bolts are available; however, mortised auto door bottoms are not available. 

On-site Modifications to Fire Doors

Fire-rated doors must be hung such that there is a maximum 1/8" (3.2mm) clearance between the frame and door. A maximum 1/8" (3.2mm) clearance between the top leaf and the bottom leaf of dutch door, or transom and door, or between leaves of pairs, is also allowed. 

Trimming for height may be done on the bottom rail ONLY, and shall be trimmed NO MORE THAN 3/4"/19.0mm. Trimming for height is not allowed for steel doors. Surface mounted hardware must be attached with throughbolts unless interior blocking is provided. Manufacturer’s label shall not be removed, covered or painted over. 

Per NFPA 80, job site modifications for fire rated frames are restricted to the following:

1. Circular or rectangular function holes for latch bolts. 
2. Prepping area around function holes for strike plates. 
3. Installing gasketing or seals to the frame if required. 

If needed, the bottom of each frame leg may be trimmed to fit the rough opening.