Atlanta homeowner Eric Hickman says he had no idea his backyard wood deck was rotting away until it buckled to the ground as he grilled burgers during his 12-year-old daughter's birthday party last year over Memorial Day weekend.

The girl escaped injury, but watched the hot barbecue grill land on top of her 70-year-old grandfather when he, her father, and an uncle wound up under the fallen deck. The grandfather suffered third-degree burns, and both sons had broken bones.

The 25-year-old deck gave way with no warning. The culprit wasn't the deck's age, although experts estimate a deck's lifespan is closer to 15 years. The problems: improper flashing and inadequate fasteners.

An 84-year-old University Place, Wash., grandfather didn't fare as well three years earlier when a second-story house deck collapsed during a party for his grandson, who had just enlisted in the Navy.

Sixteen people gathered on the nine-year-old deck, which rocked away from the house, killing the man and injuring seven others severely enough to send them to the hospital.

The cause: The deck was nailed rather than bolted to the side of the house.

One study blames sudden deck collapses for 33 deaths and 1,122 injuries between January 2000 and December 2006. Another calculates 17 deaths and 350 injuries in the past five years.

The most tragic incident, in Chicago in 2003, killed 13 people—most of them crushed when the third–story porch fell on them—and injured 57.

And those are just the reported incidents, says Michael Morse, founder and president of DeckLok, a manufacturer of deck fastening systems, who estimates that a deck a week buckles to the ground, but isn't reported unless someone gets hurt.

Case in point: Contractor Todd Funfar, president of Fargo, N.D.–based Deck Masters, evaluated more than 80 collapsed decks during the particularly snowy winter of 1996. None involved people; none was reported to building or fire authorities.

Reported or not, such tragedies are bound to increase. Morse, who studied six years of reported deck failures, estimates that deck collapses are increasing at a rate of 21 percent a year. Building officials point the finger at do–it–yourselfers and inexperienced handymen who don't bother with code inspections. But when a deck comes tumbling down, it reflects as much on the deck industry—including professional home and deck builders and manufacturers of deck fasteners—as on the homeowner or handyman.

Some deck collapses prompt back–and–forth lawsuits that blame everyone from the home builder to the subcontractor who built the deck to the manufacturer who made the hardware to the party guests who danced on the deck minutes before the tragedy. In fact, each one has a responsibility to ensure a sturdy deck and the safety of the people who use it.

"When a deck falls down, it puts a black eye on the whole industry," says Kim Katwijk, owner of Deck Builders in Olympia, Wash., and a director of the North American Deck and Railing Association.

Yet many builders hire framers instead of professional deck builders to install decks on their new homes. And homeowners neglect to maintain their decks or have them inspected every few years to head off problems, says Katwijk, who says it's up to the home or deck builder to insist on using proven installation methods and state-of-the-art materials, and to educate owners about the need to tend to a deck during its lifespan.

That can be a hard sell. It can cost an extra $400 or so to use top-of-the-line stainless steel fasteners in place of corrosion–prone metals, even though some manufacturers admit they're sturdier than any other kind.

WHY DECKS COLLAPSE
Investigators say nearly all deck collapses occur when the deck ledger board tears away from the house, usually because the connection was anchored with nails rather than with lag screws or thick bolts, or because improper or nonexistent flashing allowed water to penetrate the ledger board, which serves as the primary mounting point for the deck and is bolted to the wall of the home. Water that gets trapped between an unflashed ledger board and the wall can cause the lumber to rot—making the connection unsound.

But the deck doesn't fall after the first raindrop gets trapped. Wood rots gradually, and fasteners loosen over time. It can take years—even decades—for the collapse to happen, but when it does, it's usually catastrophic, as virtually all collapsed decks fall when people are standing on them, save the ones that buckle under the weight of an extra–heavy snowfall.

"You can have a deck standing there for 10 years and everything so far is good, and then the next time you and some family members walk out there, it can fall," says Frank Woeste, an engineering professor emeritus at Virginia Tech.

That can happen even if the deck complies with the 2006 International Residential Code, which says decks should support 40 pounds per square foot. In September 2006, for instance, a family of four wound up in the hospital after the two adults and two teenagers stepped onto the deck of a home they were thinking about buying. It pulled away from the house, slammed against its support columns and landed upside down, trapping them underneath. The deck, built to hold 48 people, was structurally sound. But it came down under the weight of only four because the fasteners connecting it to the house pulled free.

Such stories are increasingly common as the deck becomes a standard fixture on new homes—around one-third of new homes come with decks—and owners of existing homes add countless more.

The good news: The International Code Council in May approved changes to the 2008 IRC that specify the kinds of bolts—and how many—builders should use to fasten a deck to a house. Based on three years of research at Virginia Tech and Washington State University, the new guidelines favor lag screws and 1/2 inch bolts and advise builders how far apart to space them, depending on the span of the deck joists (see "Code Changes," above). Many local governments are going a step further, requiring or at least recommending that decks be built so they can stand on their own—even if they are attached to a house.

The deck–building industry, including professional installers, trade associations, and manufacturers of decking materials and fasteners, is stepping up with campaigns aimed at do-it-yourselfers, who often skip the inspections and skimp on quality products to save money. In addition, manufacturers have fashioned longer–lasting fasteners to better withstand contact with harsh weather and corrosive wood treatments, and have created elaborate systems that anchor the deck so it supports not just vertical weight—the things and people on the deck—but also lateral weight—the movement of that weight, which occurs when people jump, dance, or walk.

"It doesn't take much for people at a party to wander outside because it's warm, to start telling a story that requires them to start jumping up and down," says Janet Arden, managing editor of DeckWorld magazine, a publication for deck builders and manufacturers of deck materials. Frank Lesh, president of the American Society of Home Inspectors, agrees: "When you've got a deck, especially when you've got young people, you're going to have a party."

One too many parties on an improperly attached deck all but guarantees a tragedy. Around 40 percent of decks are built by handy homeowners, estimates Katwijk. And too many of them are skipping the deck inspections, says Raoul Newman, assistant director for inspections for Atlanta's Bureau of Buildings.

"The biggest problems we have are with the weekend builders who go to [The] Home Depot and get a quick how-to-build-a-deck-over-the-weekend course and they don't get a permit," he says. "Will there be deck failures? They're going to happen. But probably when that occurs, you're going to find out it wasn't permitted. I would say permitted decks are properly done."

Still, notes Andy Engel, editor of Professional Deck Builder magazine, a sister publication of Building Products , decks that were permitted and inspected before code officials addressed the issues of flashing and anchoring were considered safe and sound at the time.

"In the past, decks were viewed as an afterthought on houses," says Engel. "So contractors did not take the issue of flashing them as seriously as they should have." The result: Many decks built 10 or 20 years ago were improperly flashed and are failing.

Decks, says Steve Pryor, building systems research and development manager for Simpson Strong–Tie, which produces connectors and anchor systems, "have the potential to be about the most dangerous part of our home."

Yet Lesh says he still sees brand–new decks that have been nailed to the house. "Nails are a very good attachment device, but when you put excessive loads on them, you're going to have a problem," notes Katwijk.

A TOUGH SELL
When builders replace those outdated practices with proper flashing, inspections, sturdier hardware, and extra bolts, though, they add to the labor and cost of building a deck and can create a hard sell. Brian West, regional sales manager for Grace Construction Products, which makes flashing products, says it's worth the time and money: "If you're spending $6,000 to $7,000 to build this grand deck, another couple hundred in costs is negligible."

And even though stainless steel fasteners are far more resistant to corrosion than other metals, few installers can persuade every customer to spring for them.

A one–time deck builder, Engel recalls giving a homeowner an estimate for $500 more than his competitor's because he wanted to use stainless steel hardware. "I didn't get the job," he says.

Still, says sometime deck builder Lesh: "You oftentimes get what you pay for." He advises deck and home builders whose homes include decks to push high–quality hardware on their buyers.

Baltimore remodeler Michael Humphey agrees. "There's no question that the stainless does a better job," says the owner of Great Bear Structures, who says he has never built a deck that collapsed. "I build relationships with my clients so they trust me. I recommend stainless, and they say OK."

Hardware became an acute issue for deck builders in 2004, when manufacturers replaced CCA (chromated copper arsenate), an arsenic–containing chemical wood preservative that wards off bugs, mold, and rot, with alkaline copper quat (ACQ) or copper azole for pressure–treated wood used in residential projects. They quickly learned that the new preservatives, because of their very high copper content, are about five times more corrosive to steel nails and other metal fasteners than CCA, according to the American Wood Preservers Association.

Now, builders use hot–dip galvanized steel fasteners, which add a layer of zinc to screws and bolts to prevent the steel from touching the copper in deck lumber treated with copper–containing preservatives. Or they can use stainless steel, which can be up to three times as expensive.

Some manufacturers have added a polymer layer on top of the zinc for even more protection. USP Structural Connectors found in a test that fasteners with its polymer "barrier" coating over a zinc layer lost 3.2 percent of its material weight when exposed to ACQ–treated lumber, compared with 9.1 percent for fasteners with a galvanized coating alone. Stainless steel fasteners lost .02 percent.

The test was conducted in a corrosion chamber for 120 days. Still, Todd Grevious, engineering manager for USP's central region, says the manufacturer can't correlate that to an amount of time on an outdoor deck that is exposed to the weather.

Lesh quotes an old truism that he says applies to deck building: "Pick two: cheap, fast, good. You can have two of those things, but it's not going to be all three. It can be cheap and fast, but not good. Unfortunately in the States, we go for cheap and fast."

The solution, he offers home builders and remodelers: "Be right up front with people. Tell them that your deck is going to cost X number of dollars more because it's going to be quality. Eight of 10 people will go for the cheaper bid, but two will go for the quality work, and your reputation will grow."

In the end, Lesh says, code–defying deck builders and do–it–yourselfers are keeping him—and his fellow home inspectors—in business. "I make a living finding all of their problems," he says. Katwijk says he does, too: "The home builder might hire a framing crew [to build a deck] because they don't want to pay my price, but it's guaranteed work for me in about five years."

Code Changes

The International Code Council will base its 2008 guidelines for residential decks, in part, on these calculations from Virginia Tech and Washington State University. Calculated on-center spacing of fasteners (inches) for pressure preservative-treated hem-fir or Southern pine deck ledgers attached to spruce pine fir or a 1-inch-thick laminated veneer lumber band joist for residential deck joist spans with 40 per-square-foot live and 10 per-square-foot dead loads.

Joist Span (FT)	6	8	10	12	14	16	18
Connection Details	On-Center Spacing of Fasteners
1/2-inch lag screws with 15/32-inch sheathing	30	23	18	15	13	11	10
1/2-inch bolts with 15/32-inch sheathing	36*	36*	34	29	24	21	19
1/2-inch bolts with 15/32-inch sheathing and 1/2-inch stacked washers	36*	36*	29	24	21	18	16

*These spacings were limited by a consideration of the bending strength of a 2x8 (minimum) ledger
between the bolts or lag screws. Source: Virginia Tech

How To Sell Up

Convincing a homeowner to pay a few hundred extra dollars for top-of-the-line deck hardware can be a tough sell, but it could mean the difference between a safe deck and one that collapses without warning. Deck builders offer these tips for selling safety:

• If the deck is to be part of a new home, show the buyer how little (if any) difference the sturdier hardware will cost when it's amortized over 30 years as part of the home mortgage.
• Show the homeowner that the industry, academic researchers, and government experts agree that using quality fasteners prolongs the life of the deck.
• Educate the homeowner about the common causes of deck failures: nail connections rather than sturdier bolts or lag screws; improper or nonexistent flashing; and corrosion of hardware.
• Insist on getting a building permit specifically for the deck so a building inspector will double-check the connections. Encourage homeowners who want to build their own decks to get building permits and to follow the guidelines of the building code.
• Encourage deck owners to waterproof and otherwise maintain their decks, and to have them inspected every few years.

-- BUILDING PRODUCTS