Most commercial buildings around Atlanta, from the warehouses along I-285 to the offices and apartment buildings inside the Perimeter, have steel frames on their back doors, stairwells, corridors and mechanical rooms. The door gets the attention, but the frame is what the hinges hang from and the latch locks into. A frame that is the wrong type for its wall, or poorly anchored, loosens, twists and lets the door sag, however good the door is.
Welded or knock-down
- Welded frames. The head and the two jambs are welded together at the factory and arrive as one piece. A welded frame is set in place before the wall is finished around it, so it suits new construction and block walls. It is the stiffer of the two, and the usual choice for exterior doors, stairwells and openings that take heavy traffic.
- Knock-down frames. The head and jambs arrive as three pieces and are assembled on site, usually wrapping over a drywall partition that is already built. A knock-down frame is quicker to put into a finished stud wall and easier to ship, and it is common on interior office doors. It is less rigid than a welded frame, which matters on a door that is slammed all day.
How a frame is anchored
The anchors are where most frame problems start. In a block wall, wire or strap anchors are built into the mortar joints as the wall goes up, and the jambs are often filled with grout, which makes them very hard to pry and the hardest frames to remove later. In a steel or wood stud wall, clips inside the jambs are fastened to the studs; a knock-down frame slipped over finished drywall is usually held by compression anchors that tighten the jambs against the wall. Where a frame goes into a wall that is already built, existing-wall anchors bolt through the jamb into the masonry or the structure behind it. At the floor, base clips hold the bottom of each jamb in place, so the frame cannot walk when the door is swung hard.
What to decide before ordering
- Size, handing and profile. The opening, the swing of the door, and whether the frame is single rabbet, or double rabbet with a rabbet on each side of the stop so the door can be hung from either side.
- Gauge. Sixteen-gauge steel is common on interior frames; fourteen-gauge is the usual step up for exterior and heavy-use openings, and heavier frames are used where security asks for them.
- Throat. The depth of the frame has to match the wall it wraps. A frame ordered for the wrong wall thickness does not fit, and it is a common reason a frame has to be reordered.
- Hardware preparation. Hinge preps, the strike prep and closer reinforcement are made at the factory. An electric strike, a door-position switch or a power transfer for an electrified lock needs its own prep, and is far easier to order in than to add later.
- A fire label. In a rated wall the frame carries its own label, and it has to be rated for the opening along with the door. A label painted over or ground off is a problem at the next inspection.
Replacing a hollow metal frame
A frame comes out when it is bent, rusted through at the floor, pried at the strike, or the wrong type for how the door is used. A knock-down frame in a stud wall is the simpler swap. A welded frame grouted into block has to be cut out, and the block and finish around it patched, so the estimate for that job includes the wall as well as the frame. While the frame is out, the opening is secured until the new frame and door are hung.
We measure the opening and the wall, check how the old frame is anchored and whether it carries a label, and tell you whether it can stay or what should replace it, in a free written estimate that lists the frame, the door and the hardware separately. The walkthrough is same-day when the schedule allows.