Beyond the Build

Construction Trends

Powder Activated Fasteners vs Welding

Powder activated fasteners are probably not something that is top of mind for many. But to some, depending upon the way one might have been raised in the business, there is a preference. Both get the job done, but differently.

I was talking with one of our project superintendents on a job in Blacksburg recently about means and methods for attaching different systems to substrate. He likes powder-actuated tools, which are about the closest thing to firearm you’ll find on a construction job site. Developed for ship repair in WWII, these highly specialized nail guns are used to join materials to hard substrates like steel or concrete. This “direct fastening” technology relies on a controlled explosion created by small chemical propellant charge. We’re seeing it used as a code compliant alternative to welding in the steel and metal trades for bar joists, structural steel and steel deck.

Powder-actuated fasteners are commonly used to attach medium duty curtain walls to structural steel or concrete at the perimeter of a building. Light gauge steel framing and track along the outside perimeter of a building can be fastened directly to steel framing members or concrete slab edges. It’s also common for decking. A few lessons learned as we compare these systems to welding:

Powder activated fasteners require no pre-drilling. They have a muzzle safety interlock to ensure that the gun does not discharge in an unsafe manner. They are clean and accurate, but the fasteners can be really expensive, depending on what is specified. Also, these systems can take extra labor hours to install.

On the other end is the tried and tested, welding method for attachment. While probably safer, the welding produces gases via the welding rods and fumes from the welding machines. Burnt rods are often thrown haphazardly and inexperienced welders might burn decking. Deck welds must be painted as well to keep from rusting.

To each his own…

Merrill Stewart Jr.

Merrill Stewart is Founder and CEO of The Stewart/Perry Company, a commercial building contractor based in Birmingham.