The Early Show
Contributors: Susan Koeppen
Presented on: June 24, 2009
Dangerous Decks Beneath Our Feet

Fifty Percent Of Decks Unsafe, Experts Say; Susan Koeppen Gives Tips On Sound Deck Engineering

(CBS)  It's estimated that about half the decks in the U.S. are beyond their useful life and may be unsafe, according to experts.

Early Show consumer correspondent Susan Koeppen delved into deck safety Wednesday, offering tips making, and keeping yours safe.

Bryan and Jenn Tallmadge know the importance of deck safety: The deck of their rental cabin collapsed in 2003.

The Tennessee cabin was "gorgeous" and "brand new," according to Jenn, who added, "I didn’t think anything would be wrong."

But something was very wrong, Koeppen says.

One day during their vacation, Bryan lit the grill on the deck and went inside. That's when he heard a "lightning bolt-like crash." The noise was Jenn falling 40 feet along with the two-story deck.

She survived, but suffered broken bones and third-degree burns from the grill.

The Tallmadges said the deck, which held not only the grill, but a hot tub, was only attached to the house with nails.

But cases like the Tallmadges' are on the rise, according to experts. Since 1999, structural building supplier Simpson Strong-Tie Company, Inc. reports, there have been more than 850 reported injuries and 20 deaths, as a result of deck failures.

"We estimate that at least 50 percent of decks out there, approximately 20 million decks, need some type of repair or replacement," said Ricardo Arevelo, a structural engineer for Simpson Strong-Tie.

Arevelo showed Koeppen examples of a well-constructed deck and a badly-engineered one.

On the well-built deck, Arevelo showed how recommended metal connectors reinforce the structure. He also suggested installing slats less than four inches apart. And he told Koeppen -- most importantly -- that decks should be firmly secured to a house with screws and bolts.

On the badly-engineered deck, Arevelo showed Koeppen how cracked wood or rusty nails can be detrimental materials. So should using only wood materials, instead of metal connectors. He added that using only nails, instead of heavy-duty screws, can fuel a collapse.

Arevelo told Koeppen the mistakes on the badly-engineered deck are very common.

"Sometimes, people don’t take decks seriously," Arevelo told Koeppen, "but it is very important that decks are properly built and maintained."

The average life expectancy of a wood deck, Koeppen added, is 10 to 15 years.