FAQ2021-10-13T18:54:03+00:00
What are the rough opening (RO) dimensions for a knockdown hollow metal frame?2021-08-25T00:13:27+00:00

The rough opening (R) is 2″ wide by 1″ high.

What are the rough opening (RO) dimensions for a knockdown hollow metal borrowed lite?2021-08-25T00:12:51+00:00

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

How is the throat size determined for a hollow metal frame?2021-08-25T00:11:54+00:00

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”
  • 8” block: 7-3/4″
What are the fire door rating classifications and what do they mean?2021-08-25T00:10:51+00:00
  • Class A (3 hour) – openings in firewalls that divide a single building into fire areas.
  • Class B (1-1/2 hour) – openings in enclosures of vertical shafts and stairwells through buildings and in 2-hour rated partitions providing horizontal fire separations.
  • Class C (3/4 hour) – openings in walls or partitions between rooms and corridors having a fire resistance rating of 1 hour or less.
  • Class D (1-1/2 hour) – openings in exterior walls subject to severe fire exposure from outside the building.
  • Class E (3/4 hour) – openings in exterior walls subject to light to moderate fire exposure from outside the building.
What is the largest size of visible glass that can be put into a fire-rated door?2021-08-25T00:08:46+00:00

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:

  • 20 minute fire-rated door – 1,296 sq. in. per lite
  • 3/4 hour fire-rated door – 1,296 sq. in. per lite
  • 1-1/2 hour fire-rated door – 100 sq. in. per lite
  • 3-hour flush door, no glass – per manuf. requirements​
What is the difference between rotary sliced and plain sliced veneer? What is quarter cut?2021-08-25T00:05:12+00:00

Rotary sliced or rotary cut follows a log’s annual growth rings, providing a bold, random appearance.

Plain sliced or flat cut is sliced parallel to the center of a log, creating a cathedral
or straight grain pattern, which is ideally suited for matching doors and wall patterns.

Quarter cutting produces a series of straight grained stripes that vary in width from species to species, and can also produce flake patterns, especially in oak woods.

How is the swing of a door determined?2021-08-25T22:42:53+00:00

How a door swing is determined

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