Where to Go When You're All Decked Out

“Everybody wants someone else to figure it out for them,” acknowledged Chris Tennessen, a designer at Villaume Industries. “We’ve been proactively working with builders to address deck ledger attachment, but unfortunately most don’t care. If the homeowner doesn’t buy a deck with the house, the builder is not going to worry.” Instead, Tennessen said, the builder has every reason to “pass the expenses on to any retrofit work.”

Still, there are a few who want to make sure that what they’re doing is correct. “Some do contact us, asking how to attach a deck,” Tennessen said. When they do, Tennessen is committed to “getting the right documentation to confirm what [dimensions] can be supported for deck attachments.”

Part of the problem, as Tennessen sees it, is that the building code is vague on the topic. There are few details, and the code mostly refers to dimensional lumber, not trusses. So he was happy to find a supplemental resource. “The SBCA’s online best practices resource is very helpful,” said Tennessen. “It contains a lot of helpful things to hand out to builders. Whenever I focus in on a specific challenge, I go to the SBCA website and see if there is anything new or related. I figure I should ask those who know, even if it’s just out of my curiosity.”

In this case, the SBCA Research Report (SRR) 1408-01 “Attachment of Residential Deck Ledger to Metal Plate Connected Wood Truss Floor Systems” provides construction details developed in an accredited testing lab. More important than the report itself, SBCA’s online resources feature educational materials for CMs to use in sharing the latest research and best practices, like step-by-step installation and design guides. The site is publicly accessible so that CMs can share everything with their customers or building officials.

Tennessen is happy to have the best practice guides to lean on, because they address issues that are typically out of scope for his business. For example, he said, he might design a truss to carry a 12-foot deck off the end, but that’s not all there is to consider. “Just because I designed it for the weight doesn’t mean the connection part is accounted for. I don’t do those connections; I don’t build decks.” The best practice guidance on deck ledgers bridges the gap between Tennessen’s design expertise and his builder’s installation knowledge, clarifying what the connections can actually support.

Whenever there’s potential for a problem, Tennessen argued, “you have to anticipate the client’s needs with multiple solutions. The SRR, construction details and step-by-step guide provide documentation the builders expect, and it considers all the angles.”