Which is Best to Use–Welded or Knock-Down (KD) Frames?
Hollow metal frames come in two types: fully welded and knock-down (KD). Welded frames come in a single piece with all corners welded and ground smooth. This type of frame is positioned first and partitions (gypsum board on metal studs or masonry) are built to it. KD frames come in three pieces–two jambs and then the head and are they are installed after the partitions are in place; this type of frame is usually used with drywall construction only and is not durable as the welded frames. Both types can be used where a fire-rating is needed.
