Angle Units
Angle UnitsSlip-In Door & Frame
Replace an apartment door without tearing out the old frame. Universal Fireproof Door fabricates angle units in-house: a steel door hung on a 12-gauge angle-iron frame, sized 1/8" under your existing frame so it slides right into the rabbet. Just send us the width and height.
Complete Apartment Angle Unit
Door, frame and hardware in one package — pre-hung and ready to slide into your existing frame.
Apartment Angle Unit — everything included
- Steel mortise door20-ga, 1-3/4", 90-min slab
- 12-gauge angle frameWelded, 1/8" undersized
- (3) spring hinges4-1/2" satin chrome
- Mortise lock + deadboltSolid brass, SC1 keyway
- Peephole viewer
- Door chime
A new door that slips into your old frame
An angle unit is a door pre-hung on a "slip-in" frame. We cut three 12-gauge steel flats, bend them into L-shaped angles, then miter and weld them into a single jamb. The finished unit is 1/8" smaller than your existing frame, so it slides into the rabbet and fastens in place — the old frame stays in the wall.
No frame removal
No demolishing masonry or patching walls. The existing frame stays put, which keeps the job clean and fast — ideal for occupied apartment buildings.
Only width & height
No need to measure each hinge and lock location. Give us the opening's width and height and we deduct accordingly in the shop.
Heavy 12-gauge steel
Angle-iron frames are welded from 12-gauge steel in our New York factory — built for the daily abuse of apartment and commercial entrances.
Three steps to a new opening
Measure the frame
Measure the width and height of the existing frame opening at the rabbet. Send them to us with your door type and swing.
We fabricate
We deduct 1/8", fabricate the angle frame, and hang the door on it with hinges and lock prep — all done in-house in Brooklyn.
Slide in & install
Pick up in Brooklyn or Long Island, or we deliver to your job site. The unit slides into the old frame and fastens in place.
Pre-Finished Apartment Angle Units
Slabs for Angle Units
Steel door slabs we can modify and hang on an angle frame to fit your opening.
Send us the width & height. We'll handle the rest.
Factory-direct pricing on single units or full-building replacements. Pick up in Brooklyn or Long Island, or have it delivered to your job site.
Angle unit questions
What measurements do you need?
Just the width and height of the existing frame opening. We deduct 1/8" so the angle frame slides into the rabbet — no need to measure individual hinge or lock locations. Let us know the swing (left or right hand) and any hardware you need.
Do I have to remove the old frame?
No. That's the main advantage of an angle unit. The existing frame stays in the wall and the new unit slides into it, saving demolition, patching and labor.
How is the angle frame made?
Three sections of 12-gauge steel flat are bent into L-shaped angles, then mitered and welded together to form the jamb. Everything is fabricated in our Brooklyn factory.
Can you build non-standard sizes?
Yes. Beyond our stock apartment sizes, we fabricate angle units to fit your opening. Send us your dimensions for a quote.
How do I get my angle unit?
Pick up at our Brooklyn or Long Island location, or we can deliver to your job site. Call (718) 455-8442 or request a quote online.