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Sawn Wood Versus LVL Header Strength
Question
Forum Responses
The real issue is, what is the grade of the solid oak and maple beams? With gluelam we can control the quality of the laminations and therefore the overall strength and stiffness within a narrow range. For an equal size, it would not surprise me to see gluelam with spans 50% to 200% more.
From the original questioner: The solid wood beams would be clear rift sawn lumber dried to 9% MC (no defects). The span needed is only about 5 feet and the load is for a bearing wall on a single story home. I need a table of comparison for the building inspector. Any help you can provide would be appreciated. And yes, I work at OSU, I just don't know who to ask. From Professor Gene Wengert, forum technical advisor: Call the head of the OSU Forest Products Lab. A beam is usually not considered riftsawn. From contributor W: "The span needed is only about 5 feet and the load is for a bearing wall on a single story home." In my experience, using gluelams for a 5 foot span in a single story residential structure would be like using a 50 caliber rifle to shoot a squirrel. Building code manuals (are you under the IRC code?) have tables for header sizes, and the strength characteristics for the clear species you mention would seem to exceed those of standard SPF lumber typically considered for code span tables. "I need a table of comparison for the building inspector."
From contributor Y: Being a builder in Oregon, I can say they (building inspectors) are very strict. From past experience, never use anything that doesn't have a grade stamp or has been approved by an engineer. It isn't fun to tear something out and replace. Better to smile and say yes sir and follow the code. Never try to buck the code to please the owner - it can be very expensive, I know. Try to get in touch with Scott Levengood - he is a wood extension agent for OSU. He knows what works.
From the original questioner: Thanks for the contact information. I have passed this on to the homeowner to sort out the details. Would you like to add information to this article? Interested in writing or submitting an article? Have a question about this article? Have you reviewed the related Knowledge Base areas below? 
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