FAQ

The rough opening (RO) is 2-1/2″ wide by 2-1/2″ high.

The rough opening (RO) is 2-1/2″ wide by 2-1/2″ high.

The throat size is determined by the wall thickness. Common wall compositions and their throat size:
2-1/2” metal stud, 1 layer of 5/8” sheetrock both sides: 3-3/4”
3-5/8” metal stud, 1 layer of 5/8” sheetrock both sides: 4-7/8”
3-5/8” metal stud, 2 layers of 5/8” sheetrock both sides: 6-1/8”
6” metal stud, 1 layer of 5/8” sheetrock both sides: 7-1/4”

Class A (3 hr): Openings in firewalls dividing a building into separate fire areas.
Class B (1½ hr): Openings in stairwells, vertical shafts, and 2-hour partitions for horizontal separation.
Class C (¾ hr): Openings between rooms and corridors with fire resistance of 1 hour or less.
Class D (1½ hr): Openings in exterior walls with severe outside fire exposure.
Class E (¾ hr): Openings in exterior walls with light to moderate outside fire exposure.

It depends on the rating. All glass used in fire-rated doors must be listed glass and be either ¾” wire or other listed material. Basic guidelines: 3-hour flush door, no glass – per manufacturer’s requirements.

Rotary cut: Follows a log’s growth rings, creating a bold, random look.
Plain/flat cut: Sliced parallel to the log’s center, producing cathedral or straight grain, ideal for matching doors and walls.
Quarter cut: Produces straight-grain stripes that vary by species and can create flake patterns, especially in oak.