LD1
Epic Contributor
That is like those trusses I was talking about that had angle iron tops and bottoms with round bar in between. (or sometimes little angle iron in between.)
A note about glue
I have built 5 buildings with field built trusses, the last one a monster 34' span trusses on 8ft centers ibeam rail for hoist suspended on centerline. That structure has been up for 20 years with lots of hoist activity.
Glue yellow ,white are not structural. glue line creeps under load. Construction adhesives the same. There were 2 structural waterproof glues, epoxy and the two part resoursanol . Rsoursanol is no longer available due to emissions. Epoxy is expensive. The one that still works structural, water resistant is the urea type. Indoor use only . Brown powder that you mix with water. The nails provide clamping pressure. I use plywood and over size the gussets to increase the glue area. All that said I would just buy trusses next time.
one other note I build a parallel chord truss bridge , 34' , , for the Appalachian trail, used the urea glue (indoor use only ha) . We just took the bridge down 2 years ago . It was up for 25 years and still had some life left although sagging a bit. Previously Hurricane Irene flooded the area , brought down a hugh tree which lifted the structure off its supports and sent it down stream, in one piece. Flood subsided some, we went swimming and floated it back up steam, jacked it up and winched it back into position. I can vouch for urea glue.
All this talk of OSB and trusses had me thinking about a crazy idea, that would probably never work anyway....
And would only be cost effective on larger trusses that use heavier members, like 2x8's and up......
Why not build a truss like the OSB I-joists? No ope webbing, rather all closed in with OSB and 2x4 around perimeters?
Of course not having open webs would be a drawback... But something like 6 sheets of OSB for a 4/12 pitch 40' span truss. That ~$60 and about $40 of 2x4's around the perimeter. I would "think" that would be as strong as one of them large OC spaced trusses that has 2x10 tops and 2x8 bottoms. Cause those trusses are ~$300 or so to buy? I know its a crazy idea, but I am bored.....what the heck. (I am not actually going to build trusses like this).
I am sure the first time someone had the notion to make the i-joist people called him crazy...