Volume 46, Issue 7 - September 2007

Decking Disasters
Helping Your Customers Avoid Deck Collapses
by Penny Stacey, a contributing editor for Shelter magazine.

As more and more people are choosing to spend their summers dining and socializing on outdoor decks, studies conducted by the University of Maryland and Virginia Polytechnic Institute and State University say deck collapses are rising at an ever-growing rate of 20 percent annually. Deck collapses occur when they are occupied—making the news due to the injuries, and even deaths, of those on the decks at the time of fall. Decks often fall when no one is looking, leading many to wonder not only why the decks are collapsing—but also why this has become a somewhat common occurrence.

Is There Really an Increase?
The occurrence of a deck collapse does seem to be becoming more common; a Google search for the term “deck collapse” draws more than 19,000 queries. However, the term “deck collapse” is a bit misleading—according to research, most decks don’t actually collapse, but rather detach from the house and fall sideways. 

Deck builders also see a growing trend in this area. Ray Ebersol of Decks-R-Us LLC in Lancaster, Pa., says he has seen a number of reports about this of late. However, he notes that his company has yet to have one of its decks collapse.

“I’ve heard more in the past few years,” Ebersol says, “but I’m pretty new to the deck industry, so I figured it was because I’d never paid attention to it.”

Chris Myers of Alternative Decking Systems in San Diego agrees.

“I certainly haven’t had any of my decks collapse,” he says, “but I have read of deck collapses.”

Michael Morse, the developer of a system called “DeckLok,” a bracket designed to attach a deck to a home says that his studies conclude that deck collapses are increasing at a rate of 21 percent per year—noting that it’s clear the collapses are actually increasing (rather than an increase of reports of the collapses occurring).

“It’s not just reporting,” he says. “There’s [been] no change in the media.”

The Age-Old Question
With decks collapsing at such a high rate, the next most obvious question is: why? Deck builders have a variety of theories as to what is causing this phenomenon.

Kulmar Kirk of Just Decks in Atlanta says it’s an education problem, for consumers who don’t know what to look for when shopping for a deck builder.

“There’s not a lot of education out there,” he says.

Of course, that raises the question: what should builders do to ensure the decks they build will remain standing and attached?

In addition to building by the International Residential Code’s guidelines for decks, most builders say they use certain types of fasteners to prevent chances of collapse.

“As far as what we’re doing to prevent it, we’re using hot-dipped galvanized fasteners with new treated lumber,” says Ebersol.

Kirk notes that he also uses galvanized fasteners to ensure a sturdy deck, but says another factor comes into play as well: flashing.

“[Deck builders] figure, ‘hey, we have bolts,’ [we’re] fine,” he says, “but they don’t realize it’s a combination of bolts and flashing [that's needed].”

Myers notes he builds using a post-beam attachment to ensure a strong deck.

“It certainly isn’t going to happen when you have the post-beam attachment, because those things are very stable,” he says.

In addition, Myers says building to California’s earthquake codes also assists in strengthening the decks he builds.

“Here in California we have strict seismic building codes. There’s metal on all attachments, so that really reduces the risk,” he says.

Even so, Myers notes that no matter how strong the deck attachment is—it’s difficult to know the strength of the home to which it’s attached.

“There’s one thing you can’t control—the structural integrity of the house. You can’t see what’s inside that wall,” he warns.

Morse agrees—noting that even the strongest of houses wasn’t designed to support the weight that a deck attached to the side of the house might add. “The deck is bolted to the house rim board, but the rim board is only nailed onto the ends of the house floor joists,” he says. “[The house rim board] was never designed to be the load beam that supports a deck.”

Myers also notes that he believes wetter climates likely see more deck collapses—due to the dampening of the wood to which the deck is attached. “From what I’ve read it’s a matter of ledger-to-attachment failure, whether [it’s] the actual wood rotting out or the actual ledger attached to the house, so the bolts don’t have any meat,” he says. “I would assume that you’d have more deck collapses in rainy environments. In San Diego we don’t have the rain or moist environment that they might have in Michigan.”

Morse added that with the lack of a firm foundation, builders and homeowners ask a lot of decks. “The house has a complete foundation; a deck does not,” he says. “We’re asking the deck to be exposed to the elements, year after year, and to stay structurally sound with only two parallel lines of support, the load beam and the house connection.”

Looking to the Future
While all of these factors may come into play, deck builders hope to never hear of one of their decks collapsing. What, besides using caution when building decks, can be done to provide further education on this subject?

As for education for deck builders, Ebersol notes that his company receives training from its supplier when a new fastener is available.

For Kirk, though, educating the public is what’s become important. He utilizes events such as Safety Month in February to assist potential customers. “We do free [deck] inspections at homeowners’ houses,” he says.

Kirk adds that, like other portions of a house, it’s important to educate homeowners that the deck is susceptible to damage.

“No one expects roofs to collapse either,” he says. 

© Copyright 2007 Key Communications Inc. All rights reserved. No reproduction of any type without expressed written permission.