Door Overview
| Thickness | 1-3/4" |
|---|---|
| Approx. Weight | 150 lb |
| Fire Rating | 90 Minutes |
| Door Material | 20-Gauge Galvanized Steel |
| Core | Honeycomb |
| Finish | Galvannealed (Corrosion Resistant) |
| SKU | 3484KDF-LH-334 |
34" x 84" Knock-Down Hollow Metal Door Frame – 16 Gauge Steel
A commercial-grade 34" x 84" knock-down (KD) steel door frame for 1-3/4" thick doors in drywall walls. Available in left hand or right hand and three jamb depths. Ships compact, assembles on site, and gives a clean, professional finish for new construction and renovations.
Key Features
- 16 gauge steel – heavy-duty hollow metal built for high-traffic openings
- Knock-down design – ships flat, sets into finished or framed drywall walls
- Hinge prep – reinforced for 3 standard 4-1/2" hinges
- Strike prep – welded strike reinforcement for standard latch hardware
- 2" face trim – clean, finished look on both sides
- UL labeled – for use in fire-rated openings; pairs with UFD's 90-minute fire-rated stock steel doors
Which Jamb Depth Do I Need?
Measure your finished wall thickness (studs + drywall on both sides) and pick the matching jamb depth:
- 3-3/4" – 2-1/2" metal studs with one layer of 5/8" drywall each side
- 4-7/8" – 3-5/8" metal studs with one layer of 5/8" drywall each side
- 6-1/8" – 3-5/8" metal studs with two layers of 5/8" drywall each side
Not sure? Send us your wall thickness and we'll confirm before you order.
Left Hand or Right Hand?
Stand on the outside of the opening (the side the door swings away from). If the hinges are on your left, order Left Hand; if they're on your right, order Right Hand. See the door swing chart in the photos – a Right Hand frame also works as a Left Hand Reverse, and a Left Hand frame as a Right Hand Reverse.
Specifications
- Opening size: 34" x 84" (7'-0" tall)
- Handing: Left Hand or Right Hand (select above)
- Jamb depths: 3-3/4", 4-7/8", 6-1/8"
- Material: 16 gauge hollow metal steel
- Face trim: 2"
- Door thickness: 1-3/4" (steel or wood)
- Hinges: 3 × 4-1/2", located 5", 37-1/4", 69-1/2" down from the inside top of the frame to the top of each hinge
- Wall type: Interior drywall
Where It's Used
- Apartment buildings and multifamily renovations
- Offices, retail and commercial buildings
- Schools, healthcare and institutional projects
- Utility, storage and mechanical rooms
Frequently Asked Questions
Is a knock-down frame as strong as a welded frame?
Once installed and anchored, a 16 gauge KD frame performs well in most interior openings. Welded frames are preferred for masonry walls and very heavy-use openings – ask us if you're unsure.
Can I install it in an existing wall?
Yes. Knock-down frames are designed to slip over finished drywall, which makes them a common choice for renovations.
Do you have the matching door?
Yes – we stock 34" x 84" steel doors, 1-3/4" thick, 90-minute fire rated, prepped to match these hinge locations.
Built by Universal Fireproof Door
A Brooklyn steel door manufacturer since 1924. UL Listed and NYC MEA Approved. Pick up in Brooklyn (1171 Myrtle Ave) or Brentwood (75 Emjay Blvd), or call 718-841-0767 for help choosing the right frame.
Listings & Approvals
Certifications & Standards
| Fire Rating | 90 Minutes (UL 10C) — tested and certified for 90-minute fire protection |
|---|---|
| FDNY Certificate | Approved for installation in all NYC boroughs |
| NYC DOB Approval | Meets all Department of Buildings requirements |
| IBC / NFPA | Conforms to International Building Code standards |
| ANSI | Meets ANSI A250.8 standards for commercial steel doors |
Required Tools
- Level (minimum 48")
- Hammer drill with masonry bits
- Screwdriver set or impact driver
- Shims (wood or steel)
- Safety equipment (gloves, glasses)
Installation Steps
- Verify opening dimensions and ensure rough opening is plumb and square.
- Position frame in opening and secure with temporary bracing.
- Level frame using shims at anchor points.
- Install anchors per specifications (typically 12" from corners, 24" on center).
- Verify door operation before removing temporary bracing.
- Install fire-rated seals and threshold.
- Apply required labels and conduct final inspection.
What's the lead time for custom sizes?
3-5 Business days, Next day expedition available
Does this come primed or painted?
For an additional fee
Is installation included?
No
Trusted by NYC contractors & property managers


Easy transaction, fast courteous response and they offer discounts.Most importantly, they truly value their customers.Work done was excellent and product was great quality.I am very satisfied.

If I could give Universal 10 stars I would, from their communication, quality of work, and their employees, I was genuinely impressed by them all. I had 2 doors installed in my facility by their crews and they did phenomenal work. I had ...


I had commissioned them to design, fabricate, deliver and install a really beautiful Full French Motif Door for the main entrance to one of my clients Mix Use Residential buildings in Brooklyn Heights, NY.Not only did they deliver a gre...


We told them what we needed and they worked with us to get our beautiful front entry door. We needed a high security option for our office front.Universal are thorough in their email and phone communication to avoid any errors on sizing ...

The entire team was professional, efficient, and reliable. A special shoutout to Lorena, who was absolutely amazing, knowledgeable, responsive, and a pleasure to work with. She made the whole process smooth and stress-free. Highly recomm...


We needed - what else - fireproof doors. Called this place, they sent someone to take the measurements, we were provided with a quote, ordered the doors, they were manufactured, and installed. All was done professionally and perfectly....

We have ordered several fire rated doors for our NYC properties and Lorena is a pleasure to deal with. They can usually provide an estimate for door replacements just with pictures, making my life easier, install is seamless and turnarou...


I was a bit nervous about my choice to choose UFD. Truth of the matter is everything was handled with care, from customer service, estimate, fabrication and install. Any questions or changes that needed to be done, where answered and cha...


We have been using them for over 15 yearsFrom start to finish always a smooth processProfessional at its finest


their work was professional and much neater than I thought it would be considering the doorframe butted right up against new Sheetrock on the inside,which they didn’t leave a scratch on it 👌,,, the price was great, and anyone I spoke to ...
Why contractors buy from Universal Fireproof Door
We're not a reseller — we're the fabricator.
Main fabricators, not a reseller
Every door is built in-house. No middlemen, no markup.
Made in New York
Fabricated on Long Island. Local pickup and same-day service in NYC.
Fast turnaround
Standard doors ship in 24–72 hours. Custom sizes handled quickly.
Bulk order discounts
Competitive pricing for contractors, property managers and developers.
Special requirements
Non-standard sizes, custom preps and special hardware, built in our shop.
FDNY + UL certified
Meets NYC building codes and fire safety standards.


























