Sistering LVL with a 2x10
Sistering LVL with a 2x10
(OP)
I have a few joists that need to be reinforced, and was wondering how you guys feel about using LVL with a 2x10. Obviously different strength, What procedure would you use to check any design?






RE: Sistering LVL with a 2x10
It's likely that the size of LVL to take the entire anticipated load is not incredible.
RE: Sistering LVL with a 2x10
DaveAtkins
RE: Sistering LVL with a 2x10
Edit: just realized I got the 2x10 and LVL backwards, fixed it
RE: Sistering LVL with a 2x10
RE: Sistering LVL with a 2x10
(Hmmmn. somehow that seems rather incestwous, doesn't it?)
If nailed, the two WILL slip and slide as the nails lose the grips over time, as the wood dries, and as the wood swells with humidity. the weaker of the two will take almost all of the load until the stretched joint pulls tight, then the weaker will keep its load and more of the new load will be pickked up by the stronger sister.
If firmly bolted, the two will move much less with respect to each other, and the load will be shared proportionally earlier in life. But bolts do tend to weaken (loosen) and so the load will shift a little over the rest of the life of the sisters.
Well-glued and bolted with start off with both sisters sharing the load much closer to their theoretical values. But they have to be well-glued. And firmly bolted for the theory to work.
RE: Sistering LVL with a 2x10
RE: Sistering LVL with a 2x10
If the existing 2x10 isn’t broken, another 2x10 would almost double the cap’y. If you want to do something constructive, jack the existing 2x10 up so it is slightly cambered up before you install the new member. Do this jacking slowly and listen for any serious cracking sounds from above. This will make the installation easier and cause the two members to share the load in proportion to their relative flexural stiffness, once they are nailed together properly. You might hold the new member down just a bit (1/16th or 1/8"), so that it doesn’t disrupt any floor sheathing nailing to the existing joist.