Shortly after everyone had lined up on the deck for their post-prom moment, the structure gave way. The one-story fall didn’t result in any injuries, but that’s not always the case when a deck collapses. A study by Morse Technologies reported 179 deck collapses nationally, killing 33 people and injuring 1,122 between 2000 and 2007.
Decks fail for various reasons, notes construction engineer Frank Woeste, who helped develop deck code standards through testing at Virginia Tech. What most often happens, he says, is that the ledger board connecting the deck structure to the house band detaches. That, Woeste says, can happen either because the connection isn’t properly flashed, because fasteners aren’t long enough, or because fasteners aren’t correctly sized and yank out when, over time, they’re subjected to continual gravitational force.
Code Change
After 2000, code prohibited use of nails in joining deck ledgers to the house band. But there are, Woeste points out, still plenty of decks out there that are attached by nail. Compromised railings or stairs are another issue. “Those are the two critical elements,” Woeste says. “The ledger connection and the guard rail posts.”
Dennis Schaefer, a one-time deck company owner and now marketing and business consultant in Michigan, remembers being called out to do a deck inspection where the structure was so obviously compromised that he refused to set foot on it. “I told the homeowner, ‘It’s going to come down one way or another. I suggest you lock the doors and don’t let anyone on it until you decide what to do.’”
The North American Deck and Railing Association (NADRA) says that 40 million residential decks in the U.S. are 20 to 30 years old, as are another 10 million commercial decks. Since experts suggest that the life of a deck is typically 10 to 15 years, any deck older than 10 years should be inspected. The suggestion, though, is relative. “It’s so much about where the deck is geographically,” says NADRA executive Mike Beaudry. “If you’re on the coast and there’s salt and wind, or up in the mountains with snow loads, the life span of a deck can be far shorter.”
Who Inspects?
The question for homeowners is: Who inspects that deck to determine stability and safety? Some deck companies offer a deck inspection service.
At The Deck Inspector in Lombard Illinois, such inspections start at $249.00. The company began offering this service in 2013 and forsaw a great demand from responsible homeowners throughout the Chicago area.
Woeste feels not all contractors are qualified to inspect decks and that most homeowners would have little idea of how to look or where. His suggestion: Homeowners who are seriously concerned should hire a registered professional engineer. “Have him determine what the deficiencies are,” Woeste says. “Then your professional remodeler goes in there and does the work, based on what the engineer said.” —Jim Cory