Wednesday, November 25, 2009

Another expert opinion on roof trusses

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Editor
Island Packet
November 19, 2009
Hilton Head Island, SC 29938

I have followed reports by the Island Packet about defects with roof trusses in Sun City. As a professional engineer (licensed NJ, PA, MD) with 32 years experience, I often evaluate roof trusses for new construction and existing buildings.

After the 2007 articles, about inadequate valley truss connections, I posted extensive comments on the Island Packet web site. I can no longer find those comments online. However, one key point was that the valley truss connection defect is an indication of additional deficiencies with design and construction of the roof truss installation. I have posted new comments along with the new article published Sunday (11-15-09). However, it is difficult to find the article on the web site now (http://www.islandpacket.com/news/local/story/1036437.html). If you search using “Archive”, the new comments are actually missing.

A separate article also published Sunday (11-15-09) describes problems recently discovered with lack of web bracing. Reasons for this typical, widespread defect are described in comments I have posted online (http://www.islandpacket.com/news/local/story/1036436.html).

Concerned homeowners should hire an independent, qualified professional engineer, licensed in South Carolina, to evaluate design and construction of the entire roof truss system. The most important issue is whether or not proper tiedown connectors have been installed at the ends of the main (long) roof trusses, to resist large uplift forces that will occur during a hurricane. Proper connections must also be provided within support walls so that wind uplift forces from main roof trusses are distributed down to foundations.

John F Mann, PE
1212 Main Street
Belmar NJ 07719
732-556-6080

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