90-Minute Therma-Tru Split Steel Frame

Note: Reeb no longer offers Therma-Tru steel-edge doors. This information will remain available as a reference.

Split Steel Frames are two pieces allowing for an easier installation but also a variance in size. When put together, they have the appearance of a double rabbeted frame. When finishing walls or replacing a unit, the exact size of the finished wall may not be known; split steel frames allow for an adjustment space to fit these walls.

The Therma-Tru Split Steel Frame is fabricated from galvanized steel and factory coated paint finish for rust inhibition and superior paint adhesion. The base of the frame is 18-gauge while the closure is 22-gauge with 1” of adjustability. The base frame is kerfed to receive foam weatherstrip. It has been tested and can maintain a 90-minute fire rating. The frame is prepped for 4” Therma-Tru hinges that have a 1/4″ radius. The strike side is prepped with a 2-3/4” t-lip strike. Reeb’s stock frames are undersized to best pair with the Therma-Tru 90-minute steel-edge doors.

Jamb Depth

The jamb depth is dependent on the sill used and the height of the unit. A standard fire sill in a 6/8 unit can range from 4” to 8-1/2” jamb depths; if the unit is 7/0 then the jamb depth can only be 4-1/2” to 7-1/2”. A public access sill in a 6/8 unit can range from 4” to 8-1/2” jamb depths; if the unit is 7/0 then the jamb depth can only be 4-1/2” to 5-1/2”. There is also a no sill option and this only works with jambs that are 4-1/2” to 5-1/2” in depth.


Updated on July 14, 2021

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