I am looking at johns plans for 20x30 1.5 story loft floor. specifically the read me first booklet that john includes. on page 3 - 20a there are stair options listed for the loft. I am looking at the one labeled loft plan (not the u stair). It calls for double 2x12s on each side of the stairs and 49.5 in double 2x12's for the stairs to attach to.
Now here is my question, I assume if i am using i-joists, that I would just double those up on each side of the stairs. But what do I use for the 49.5in part? Is that two sets of i-joists. Also I assume I will need special hangers to mount the 49.5in joists/2x12's.
Thanks in advance.
The best advice is to view the website of your manufacturer for guidance on floor openings. They all have pretty good framing pictures specific to their product. Determine what rough opening you want and adjust the framing accordingly. Here is one example:
http://www.ilevel.com/literature/TJ-9001.pdf
Your local lumber yard likely has access to the manufacturer's Rep who can provide customized information for their products. The major suppliers have builder support specialist for questions like this.
Manufacturer specs trump anything on an engineered product, that said, I've always used LVL's in that area.
Don - in reference to the LVL are you referring only to the double 2x12's between the joists that the stairs attach to. Or are you saying use LVL for all of the double 2x12's on the plans when using the ijoists.
I typically use a doubled LVL on each side, replacing the common I joists, and a double LVL header to carry the short I joists. The supplier should be able to give you a package deal including I joists, LVL's, hangers, etc and design work for the entire floor system.
thanks this is making more sense... are the hangers just for the short lvl? I assume the longer lvl and ijoists will just sit on the ledger nailed (to the ledger and stud) without a hanger correct?
It would be better to take a point load like that straight down by putting studs directly under the lvl's. These are "special" hangers to accomodate the thickness of the doubled header lvl's.