Hollow metal doors are the standard in commercial construction for a reason. They deliver the durability, safety, and performance that busy facilities rely on every day. Whether you’re outfitting a new project or replacing an existing door, choosing the right hollow metal door is essential for long-term reliability and code compliance.
At Doors Unlimited Inc., we supply high-quality hollow metal doors, frames, and hardware built for commercial environments. This guide breaks down what matters most so you can confidently select the right door the first time.
1. Door Gauge: How Thick Should Your Steel Door Be?
Hollow metal doors come in different steel gauges.
The lower the number, the thicker and stronger the steel.
We offer the two commercial-standard gauges:
16-Gauge Steel
- Heavy-duty
- Best for exterior openings
- Ideal for high-abuse areas
- Provides maximum strength for demanding environments
18-Gauge Steel
- Standard duty
- Perfect for interior commercial spaces
- A cost-effective option when heavy abuse isn’t expected
Which one to choose?
- Go with 16-gauge when you need extra strength and durability.
- Choose 18-gauge for interior doors that don’t take as much impact.
Both options are 1-3/4″ thick, commercial grade, and built for everyday use.akes sense.
2. Fire Ratings: Know Your Building Requirements
Many commercial openings require fire-rated doors.
Our hollow metal doors can be rated up to 3 hours, making them suitable for:
- Stairwells
- Mechanical rooms
- Corridor doors
- High-occupancy areas
- Code-driven commercial applications
If your building inspector or architect requires a labeled opening, hollow metal doors are the safest and most reliable choice.
3. Choosing the Right Hollow Metal Frame
We also supply matching commercial-grade frames:
Knock-Down (KD) Frames
- Ship in pieces
- Easy to assemble on-site
- Best for drywall or renovation projects
Welded Frames
- Ship fully assembled
- Strongest option
- Best for new construction and masonry walls
Your frame choice plays a major role in installation ease and long-term durability.
Finish, Reinforcement & Construction Features
Our hollow metal doors are built to meet industry standards, including:
Construction Features
- 1-3/4″ thickness
- 16- or 18-gauge steel
- Cold-rolled or galvanized steel options
- 7-gauge hinge reinforcement
- Channel-reinforced steel sheets
Finish Options
- Factory primer (paint-ready)
- Galvanized for moisture-prone areas
Optional Door Prep
- Glass lite kits (various sizes and shapes)
- Louvers for airflow
- Hardware prep (hinges, locksets, closers, panic hardware, etc.)
These upgrades allow you to customize the door for your exact application without extra fabrication on-site.
At CommercialDoorsOnline, we supply both types, with full customization, hardware and support—so you get the right door for your building’s actual needs. If you’re ready to explore quotes or need help determining the fit, we’re here to help.