A Smarter Way to Hang Ductwork and Equipment
For decades, HVAC contractors have relied on threaded rod and duct strap to suspend ductwork and equipment. While common, these methods can be slow, cumbersome, and hard to adjust — especially with round ductwork. Anyone who’s ever tried to wrestle with duct strap knows how difficult it can be to cut, bend, and secure properly while keeping the duct level.
Cable suspension offers a modern alternative. With pre-engineered kits, lightweight cable, and quick-locking wire fasteners, HVAC contractors can hang ductwork, units, and line sets faster, easier, and with a cleaner finish.
Where Cable Suspension Works Best in HVAC
Cable systems are versatile and can support a wide range of HVAC components:
- Round ductwork (spiral, double-wall, and more)
- Rectangular ductwork (supply and return)
- Air handling units (AHUs) / fan coil units
- Chillers / rooftop packaged units (where applicable indoors)
- VRF / VRV indoor cassettes and line sets
- VAV boxes and diffusers
- Condensate drain piping (lightweight but often overlooked)
Benefits for HVAC Contractors
Switching from threaded rod and duct strap to cable suspension delivers real jobsite advantages:
- Faster Installation – Pre-engineered kits cut down on measuring, cutting, and threading rod. No more struggling with awkward duct strap.
- Lower Labor Costs – One installer can often handle cable solutions that would normally take two.
- Adjustable on Site – Wire fasteners allow fine-tuning heights in seconds.
- Cleaner Appearance – Minimal hardware and slim profiles for a more professional look.
- Space Saving – Slim cable takes up less room than bulky strut or rod systems.
- Improved Safety – Less cutting, grinding, or heavy lifting overhead.
Installation Examples
- Round duct suspended with cable instead of duct strap.
- Large rectangular duct supported by multiple suspension points.
- VRF cassette and line sets hung neatly with cable, avoiding clutter.
Load Capacities & Compliance
Cable suspension systems are engineered and tested to meet specific load ratings. Depending on the manufacturer, HVAC loads such as large ductwork or AHUs can be fully supported by cable kits.
Most major systems comply with SMACNA and ASHRAE guidelines, giving contractors peace of mind when switching from threaded rod. Always check manufacturer data sheets for specific load ratings.
Common Questions
Can I hang rectangular duct with cable suspension?
Yes. With the correct brackets or trapeze hangers, rectangular duct can be securely supported by cable suspension. The cables transfer the load directly to the structure above, while the brackets or strut spread the weight evenly across the duct. This reduces the risk of deformation and ensures compliance with SMACNA guidelines. Most manufacturers offer hardware designed specifically for rectangular duct applications, making installation fast and reliable.
What sizes of duct can be supported?
Cable suspension systems can handle a wide range of duct sizes—from small branch lines to large main trunk ducts. The determining factors are the weight of the duct, the spacing of the supports, and the load rating of the chosen cable and fastener kit. With options ranging from 50 lbs to over 700 lbs per drop, there’s a cable solution for nearly every HVAC application. Always verify the total duct weight against the capacity of the suspension kit to ensure a proper match.
What are the advantages of using cable instead of threaded rod?
Cable suspension eliminates many of the labor-intensive steps of traditional threaded rod installation. There’s no cutting, no hot works permit needed, no hauling and tracking rod lengths, and no endless spinning of nuts and washers. Cables are lightweight, adjustable on-site, and trimmed to length with simple cutters. This often reduces install time by 50% or more, leading to significant labor cost savings (labor can account for up to 60% of project costs).
Check out “Advantages to using Cable”
Is cable suspension code-compliant and safe?
Yes. Cable suspension kits for HVAC are designed, tested, and certified to meet industry standards such as SMACNA, UL, and ICC. Each system is manufactured with built-in safety factors—often4:1 or 5:1 —to ensure long-term reliability. When installed according to manufacturer instructions, cable suspension is just as strong and safe as threaded rod, while offering far greater flexibility and ease of adjustment.
What tools do I need?
Installation requires very few tools. Typically, you’ll need cable cutters (to trim excess cable cleanly) and the supplied fasteners that lock the cable at the required height. For trapeze systems, you may also need basic hand tools to secure the strut or brackets to the cable. No specialized power tools or heavy equipment are necessary, which keeps setup simple and reduces jobsite clutter.
Product Solutions
Cable suspension systems are available in pre-cut lengths or bulk spools, with a wide range of wire fasteners designed for HVAC applications. Many HVAC suppliers now stock complete kits, making it easy to adopt cable suspension on your next project.
Upgrade Your HVAC Installs
Ready to leave duct strap and threaded rod behind? Cable suspension helps HVAC contractors save time, reduce labor, and deliver cleaner installs.