Microlam vs hanger size puzzle.
constantremodeler
| Posted in Construction Techniques on
My engineer specified a 5-1/2 x 7-1/4 Microlam beam supported by Simpson WNP608 joist hangers. All the suppliers I’ve checked say Microlam only comes in 1-3/4″ thickness so we would sister 3 pieces. That makes 5-1/4″ x 7-1/4″. I thought the engineer made a typo but then there is the hanger. It’s pocket is 5-1/2″ wide. Neither Simpson or USP seem to make a 5-1/4″ hanger. I would think the hanger makers and engineered lumber people would be in sync on this. What am I missing?
Replies
Quick google search showed GP has micro at 3 1/2 in. wide.
This means your supplier needs to go looking, or you contact engeneer to find out manufactoror
confirm the dimension with archy, then hanger with simpson, allot of the hangers they make in a range of widthes, you just specify what you want ..
If your engineer specified a one piece at 5-1/2" wide microlam, then you have to use a one piece 5-1/2" microlam. Your lumberyard is useless, find a real one. Every lumberyard sells 3-1/2 and bigger.You can't just replace it with (3)1-3/4" microlams because they carry a different load than a one piece microlam. Call the engineer first before you order these. It might be alright if you have a dropped beam compared to a flush beam with joist hanging off the beam.
joe,
i'm pretty confident that his yard is correct that the brand name "Microllam LVL" from Weyerhauser only comes in 1 3/4" thickness
anything thicker than that is "Parallam PSL" also from Weyerhauser
http://www.ilevel.com/literature/TJ-9000.pdf
carpenter in transition
I'd be confident to say that the engineer is going to be comfortable using a built up system of three lvls, but you should double check that and get a nailing pattern.
Typically, if you built up three of these lvls and tried to jamb them into a 5.25" hanger, you'd have a "too tight" fit. I know....the numbers say there will be a 1/4" slop but experience has proven that to be not true.
Your 5.5" hanger will be perfect for a 3 ply built up lvl beam.
Bob's next test date: 12/10/07