Many of us remember the horrific deck collapse in Chicago in 2003 that killed 13 people and injured 57. While that incident sparked a renewed interest in deck safety, the general interest does not appear to have been long-lasting. DeckLok, a manufacturer of deck engineered connections, estimates deck collapses are increasing at an average rate of 21 percent a year. And, sadly enough, just about every deck collapse occurred while someone was standing on it. Bad news in a country where one-third of all new homes has a deck.
What causes a deck to collapse? Nearly 92 percent of all deck collapses are due to failure of the deck-to-house attachment assembly. Poor fastening or improper (or nonexistent) flashing contribute to the process of failure. Decks should be secured using lag screws or thick bolts, not nails. And flashing should be installed to prevent water damage to the wood. Water damage is an insidious threat that develops over many years, and many homeowners are not made aware of it until the deck fails.
To ensure deck safety, do-it-yourselfers should take note to get a building permit and build their deck according to code. And given the cost of secure, corrosion-resistant fasteners (an additional couple hundred dollars) relative to the cost of building a complete deck ($6,000-$7,000), homeowners should be encouraged to not skimp when it comes to safety. Waterproofing and having decks inspected every few years will also increase your chances of enjoying a safe deck for many years.