What Washington & Lee University officials are calling a “close call” should be a wake-up one for UVA students planning to celebrate this weekend. During a W&L party in Lexington last weekend, a deck on a house with as many as 80 people on it collapsed, injuring nearly 30 students and sending 22 of them to the hospital. Luckily, no one was seriously injured in the May 14 incident.

According to the North American Deck and Railing Association, that’s not always the case. Since 2000, there have been more than 30 deck collapse fatalities, and 75 percent of the people on collapsing decks get injured or killed. What’s more, there are 40 million decks in the country more than 20 years old.

“Every weekend, somewhere in the country, a deck collapses or someone falls through a deck rail,” says Joe Loferski, a Virginia Tech professor of wood science who has been researching the causes of deck collapses since 2000.

A nearly identical disaster occurred during a weekend party at Virginia Commonwealth University in 2008, when a second-story deck collapsed and injured 20. And in 2003, the deadliest collapse happened in the north side Chicago neighborhood of Lincoln Park when a third-floor wooden balcony collapsed during a party— attended mostly by young people in their early 20s— and took out the second and first-floor balconies on the way down. Thirteen people were killed and 57 injured. Initially, overcrowding was to blame, but later it was discovered that the balconies had violated a number of construction codes.

However, such incidents apparently haven’t been enough to improve deck safety awareness.

“We found many poorly maintained decks,” says Charlottesville building inspector Tom Elliott, whose department spent a week earlier this month offering free deck inspections as part of the City’s Building Safety Week.

“People think that treated wood will last forever and don’t maintain them,” says Elliott. “The wood does deteriorate— and especially the fasteners.”

Among the danger signs Elliott observed were decks fastened to the house only with nails, which can work their way out over time, and decks with no flashing between house and the deck, which can cause the house framing to rot.

“The attachment to the house is critical,” says Elliott. “If nails are the only attachment, then additional lag screws or thru bolts need to be installed.”

“It’s usually the connection, not the wood, that fails,” says Loferski. “Ninety percent of decks rely on their connection to the house for their stability.”

Loferski points out that free-standing decks are much stronger and safer, but they are not common in the construction industry. Indeed, according to building inspectors who examined the W&L collapse, the bolts that were supposed to have secured the deck to the side of the house had been attached merely to the wood siding and sheathing, not to the solid 6-inch framing beam behind them.

Elliott says that decks built on a home’s shady side will fail quicker, and that guardrails that have been notched, or cut away, at their base or secured with nails are particularly weak.

“A woman was killed in Charlottesville in 2003 after falling through a deck guardrail system that had not been maintained properly,” says Elliott.

Since the 2003 tragedy, Elliott says, the City has been incorporating findings from Loferski’s decade-long Virginia Tech study on deck collapses into code requirements for new deck construction. Loferski found that most of the common methods of guardrail construction methods failed his group’s safety tests.

“Contractors now understand what we require,” says Elliott, “but it took about five years.”

To learn more, Loferski recommends that people read guidelines from the American Wood Council, which are based on his findings, or pick up a copy of his book, Manual for the Inspection of Residential Wood Decks and Balconies.

Sadly, many deck/balcony collapses happen during joyous occasions, as friends and family gather to celebrate. Indeed, one of the more tragic local collapses involved the failure of a Jefferson-designed “propped cantilever” balcony amid graduation festivities on the UVA Lawn.

On the morning of May 18, 1997, just ten minutes before the ceremony was to begin, the balcony attached to Pavilion I collapsed and ended up “pancake style” on the sidewalk below, according to a rescue worker.

According to news reports at the time, graduation went on uninterrupted as doctors from the crowd were called in, and rescue workers struggled to access the Lawn. One of the injured was a 12-year old girl with broken arms, legs, and ankles. Remarkably, no one was trapped under the balcony structure. But when the carnage was tallied, a graduate’s grandmother had died, and 18 others were injured.

Later, it was determined that one of the four iron rods that supported the balcony from the roof rafters, a Jeffersonian innovation that had held for 175-years, was almost completely corroded where it connected with the balconies’ face beam.

The balcony received a visual inspection in 1994, under the direction of J. Murray Howard, the curator and architect for the Academical Village at the time. Unfortunately, a close look at the structure wasn’t enough to detect the corroding wrought iron rod beneath the surface of the wood.

The family of Mary Brashear, the 73-year old woman killed in the accident, sued Howard, the State of Virginia, and the architectural firm that conducted the 1994 inspection. In May 2000, the family was awarded $790,000. Previously, 13 other claims were settled for $601,500. Howard left his post at the University in 2002, and five years later, at age 60, Howard died of unknown causes at his home in Albemarle County.

The balcony was eventually restored, says the University’s chief facilities officer, Don Sundgren, but the iron rods and fasteners on all seven pavilion balconies were replaced with modern materials that better resist corrosion.

Today, Sundgren says the balconies are inspected annually by licensed structural engineers.

“Adjustments are made if required,” he says. “Also, the loads on the balconies, determined primarily by number of people, are restricted.”