Where the doors are fire rated, these clearances are regulated by NFPA 80, “Fire Doors & Other Opening Protectives”. The clearance between the door and frame shall be a maximum of 1/8″. The clearance between the meeting edges of pair of doors shall be 3/16″. The clearance from the bottom of the door to the bottom of the frame should be a maximum of 3/4″. The clearance between the face of the door and the stop shall be 1/16″. See SDI 100 A250.8-2.1.8 for complete specifications.
While the clearances of non-fire rated openings are not regulated by the Building or Fire Code, they typically will follow the same values as a rated door.
Refer to ANSI 250.8 paragraph 2.1.8 entitled “Design Clearance” and the subparagraphs underneath that. Those paragraphs specifically and clearly delineate and define the design clearances for between the door and the frame, between the meeting edges of pairs of doors, and the clearance measure from the bottom of the door to the bottom of the frame.
If a metal door has a gap between the meeting edges of a door pair that is greater than 3/16″ (1/8″ plus the 1/16″ tolerance), can the deficiency be overcome by applying a metal astragal?
If grouting is done properly it will not cause any issues with the frame. It will actually improve the sound deadening qualities. Unfortunately, thin pumpable slurry is often used and the excess water in it causes rust. Grout should always be hand troweled, never pumped.
For fire rated openings, you should verify with the frame manufacturer that if a bituminous coating is used to protect the steel frame against any corrosive effects of the grout its use will not negate the fire protection rating.
Grouting will not make a properly anchored frame any sturdier. In fact, drywall slip-on frames have passed fire and hose stream tests, cycle tests, and even impact tests with only anchoring.
No. Grouting should never be specified for drywall construction. When grout is drying, the moisture only has two places to go. The first is into the drywall, which weakens it. This could hinder the frame’s integrity or ability to retain anchors. The other place the moisture could go is into the hardware or the bottom of the frame, which may result in rust.
There are a small number of contract hardware and hollow metal distributors that have the capability to manufacture frames.
The distributor welds the frames in most cases. Many of them can modify doors and cut in glass light units as well. Distributors are often involved in fire labeling programs too, allowing them to label the door and frame.
Yes, ANSI A250.11 provides recommended erection instructions for steel frames. Please reference SDI-122 to troubleshoot an issue with a frame that has already been installed
It depends on a variety of factors such as the condition of the wall, reinforcements, and frame. You will also want to verify the gauges of the door and frame are compatible, and also that the hinge and strike locations match.
It is best to inquire with the door supplier for fire rated openings.