Is Your Deck’s Safety Up in the Air?

John Rickauer

We all love getting outside and enjoying time with friends and family, and grilling up some tasty brats on our decks as the weather begins to warm up. Unfortunately, we also watch the news and occasionally hear about deck collapses and resulting injuries. When that happens, you might wonder if your deck is safe or if something similar could happen to you.

The National Association of Home Builders reports that wood decks “have a life expectancy of about 20 years.” The North American Deck and Railing Association reports that “40 million decks in the United States are over 20 years old.” Many of these decks were constructed before more stringent building codes were adopted to address deck safety. Given these statistics, it is apparent that due to age, poor maintenance, and/or improper original construction, a large number of existing decks likely require repair and/or replacement. In some communities, all or many of these decks are a part of common property, such that their maintenance, repair and replacement is the responsibility of the community association. Depending on the size of the community, this can result in a potential cost and liability issues reaching into the millions of dollars. This article will focus on the most common types of deck failures.

Attachment to Building The vast majority of deck collapses involve failure at the connection between the deck and the building. There are many methods of attachment used in the construction of decks, but most generally rely on mechanical fasteners to attach the framing of the deck to the framing of the building. The failure of this connection can occur for a variety of reasons. A common type of failure is caused by the use of improper fasteners such as nails instead of lag screws or bolts. Failures may also occur when the deck ledger is attached through a non- structural element rather than directly to the building framing. These non-structural elements may include fiberboard wall sheathing, as was commonly used several years ago (Photo 1), or exterior finishes such as stucco (Photo 2). Ledger fasteners are generally intended to provide shear (downward) resistance across the section of the fastener. When installed through a non-structural layer, the ledger fasteners must cantilever from the building to carry the deck load. This cantilever action results in bending forces along the length of the fasteners that they are far less able to resist.

24 Community Associations Journal | March 2014

Photo 1: Ledger attachment with nails through fiberboard

Photo 2: Ledger attachment with deck screws through stucco