Knock Down Frame

A hollow metal door frame shipped in three or more pieces for field assembly, rather than pre-assembled (welded) construction. KD frames simplify delivery, allow installation around existing walls, and reduce shipping damage.

Components include two jambs and a head (plus mullion for pairs) with interlocking connections. Assembly uses clips, screws, and sometimes field welding at corners. Base anchors, jamb anchors, and header anchors secure the frame to the wall.

KD frames are ideal for renovation projects where frames cannot fit through existing openings. Fire-rated KD frames are available with specific corner connection requirements. Silencer holes, strike preps, and hinge preps are factory-applied. Related: door frame, jamb. Manufacturers include Steelcraft and Timely. Shop knock-down frames.

Related Terms

Mag Hold Open

Transom Closer

Touchless Door Opener

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Since 1938, American Doors has supplied commercial doors, frames, and hardware across the U.S., growing from a Houston-based distributor into a multi-market platform serving contractors throughout Texas and Colorado. Family-owned for more than 85 years, we emphasize continuity and craftsmanship, with AHC-certified hardware specialists and experienced estimators delivering fully coordinated Division 8 and Division 10 solutions from specification through installation.

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