Timber Framers Guild Forums General General Forum Questions timber loft joists in a stick framed house

So in my 30x26 stick framed house we are using 4x6 timber joists for the upper loft floor. they will be set 2' down on the 10' wall (creating a 2' kneewall). they also run the direction of the rafters and will aid with holding the house together.

I am trying to find the best way to attach them to the wall. I intentionally did not build them ontop of the wall and build another short wall ontop of them for fear of "hinging" the kneewall. I am thinking of running them long into the wall cavity and using either truss locks or bolts to attach them to each 2x6 stud. (the other end of the joists will be dropped into a summerbeam in the middle of the house) . I am just concerned that these 14' long joists will need more support than being bolted to the studs- am i overconcerned? Or do i need a ledger block? is it better to let the ledger into every stud or attach the ledger to the face of the stud?

Second- will a drop in soffit tenon on the 4x6 mortised into a 6x10 summer beam be sufficient? these joists will be in addition to the structural ridge beam, but no collar ties in the ideal spot (for design purposes). the entire house is a cathedral ceiling.
thanks

What distance is the summer beam spanning?

Soffit tenons don't drop in from the top, they are usually inserted into the side of the beam via a mortice and tenon.

It almost sounds like a balloon frame. A face mounted ledger, I wonder how much a let in ledger would compromise the studs?

Tim

I've usually seen pockets framed in to support the timbers. Here is an article that shows them, it may also help with your other questions.

http://lancotf.com/articles/hybrids.pdf

Tim you are correct that it is a balloon frame wall- 10' tall. and the top of the joist is at 8'. I am wondering if a drop in (with timber lock pinning down)is sufficient enough. or should i consider something more like a soffit or even a dovetail to with stand the tension from the roof spreading?
The summer beam is a 6x10 supported mostly by a framed wall underneath. The total free span is only 5' with the end set into a beam pocket in the gable end of the wall. Similar to the article Will Beamer wrote last year in FHB. And i too am concerned if a a let in ledger on the framed wall would comprise my measly 5.5 fir studs.
I do not see that a drop in pocket for each joist is too reasonable as there will be 10 per wall- it truly compromises the efficiency of a frame wall (thermal at least)

If the joists are going to help resist outward thrust they'll need a tension connection from both sides - so for the wall side you could bolt to the studs. For the carry beam - maybe drop in housing with strap across the top from joist to joist.

But you'll need to understand both the floor loads and the roof loads to make sure your joinery decisions make sense...

You could also bolt a ledger to the wall and drop in the joists - but you may still need tension ties to the joists...

How about a 1-1/2", centered fork at the stud with a bolt, and the strap thingy over the summer connecting the joists?

Tim

only problem is that you are hanging the joist on the bolt...

It seems that with balloon frames both ledgers and bracing were let in. I can see why that would be bad with your design. I think a bolted on ledger in conjunction with Tim's idea would work best, and help with installation.