Hanging balloon framing off a header
Hi all- my addition project is going well, but I got a bit of an unpleasant surprise when I tore off the sheathing to put up some headers for some openings between the addition and the existing house.
The existing house’s main floor is conventionally platform framed (though they saw fit to do without a proper (stringer? rim?) joist, nailing the ends of the joists to the sheathing boards instead). I’d assumed the 2nd floor was framed the same way, and it wasn’t possible to inspect this prior to demo. But now that I’ve got the sheathing off in the affected areas, I see that the 1/2 storey 2nd floor studs are merely nailed to the sides of the joists and bear on the existing 1st floor exterior wall’s double top plate. There is neither a bottom plate for these studs nor a stringer/rim joist.
I have three headers for three openings between the house and the addition. Two are conventional (3-ply) 2×10 headers, and one is two 2x10s sandwiching a C10x15.3 channel. The original plan was to bolt the (missing) stringer joist to the new headers and then install hangers from the existing house side once the addition was dried in. Now I’ve got joists AND studs to hang somehow. And I do want to remove the two top plates of the former supporting wall in the openings, so that the headers end up flush with the new floor framing rather than below it.
How the @&#$ do I hang this framing off these headers? Could I get away with using a double hanger intended for doubled joists? Is there something else in Simpson StrongTie’s catalog which will save my bacon here? Or do I need to move these headers underneath the existing joists and studs now, regardless how ugly this will make the affected rooms? I really, really don’t want to do that regardless of the aesthetics, because it will require demo work in the existing house greatly premature of when I wanted to do it- we’re living in there while this work is going on.
Note that most of these studs will be relieved of their structural function in a six months to a year when we tear out sections of the adjoining roof structure from underneath to make room for some closets. There are engineered ties in the plans to redirect the roof load to the foundation in the areas where we’re cutting the rafters which currently bear on these studs.
I also don’t want to ask my engineer or my inspector for their suggestions, because both will suggest something horrible and impractical and then insist that I do it their way. They’re both more likely to accept something adequate but not their idea AFTER it has been done than they are beforehand.
As usual your suggestions are very valuable to me and I look forward to your ideas!
Replies
Unless I'm missing something in your description, you are worried because what you found when you exposed the 2nd floor framing wasn't standard platform framing and you are letting that worry carry over into how to get new headers into your exterior walls.
The headers for your new openings are always going to carry both the load(s) of the first floor ceiling joists and the load(s) from the second floor walls.
It doesn't matter whether the header carries the load of the joists via joist hangers (i.e. you are carrying your existing ceiling height through to your addition and the header is hidden) or carries the load on top (i.e. you see the beam between the two rooms).
As far as the second floor wall studs, they still bear on the header (if you have to cut them shorter then you do), or they bear on tne existing double top plate (if the header goes below that)
It's really all a matter of sizing the headers properly, making sure you have temporary support in place to install them, and making sure all your laods still carry down to the foundation...platform framed, balloon framed or some B@@@&&&D combination, the physics is still the same...
If I've completely missed your question, let me know & I'll give it another shot.
I wanna say use double hangars, like your thinking, but there is a problem with that suggestion since I can't see in person exactly what you got. If these studs are well nailed to the joists, IT sounds workable. A better way might be to sawzall 3" of the lowere part of the stud(measure up three inches from the top of the joist) and slam a double bottom plate in there. This makes a conventianal wall framing. In addition, I would put blocking between the joist, (PREFERABLY 2 layers), and bolt this to your new rimjoist which you say you are installing. Put thew blocking in after you install the hangars. You may want to appraise your engineer of the conditions now that you have everything opened up. He or she may have a n even better solution.
Molten,
If I've gotten the correct picture, you will be cutting 6" off the ends of the joists over the top plates to make room for the 4 1/2" x 10" header + 1 1/2" rim joist. And you've got stud ends in the way.
Elsewhere, you need to trim 1 1/2" from the joists to make room for the rim.
First problem, supporting the wall while you put the headers in. Scab a 2x10 on each side of the wall over the header location, extending 3 or at least 2 studs past on each end. Nail these two 2x10s to each stud with 3 16d duplexes. The studs you don't cut will hold the wall up that long.
Second problem, inletting the rim joist. Can you just use rim blocks instead? Cut to fit between each stud/joist. Or set the rim blocks to the inside of the studs and insulate the resulting outer cavity.
Of course I'm probably not looking at the same picture you are.
Samt
Molten,
I'm having a tough time totally wrapping my head around your situation. Any chance of a few digital pics to help us out?
I'm guessing, from here, that the double joist hanger will be your best bet. One word of caution though... overloading a beam/header on the side can cause the beam to roll. By overloading, I don't mean undersizing, instead I'm talking about putting too much loading on only one side of it. Usually, you'd like to see the floor hung off the side of the beam and the wall load on top of it... naturally helps to stabilize it. Your very uneven loading could cause your header to roll.
Sorry guys, here's the sketch.
I don't see how your present situation is that different than what you had planned on. If I understand, you had planned on bolting the new header to the rim joist to carry the load in the openings to the addition.
It seems to me that you can always put in that rim joist. This can be done from the outside. Assuming that the framing is reasonably square and even in length, the nails that connect the new rim to the joists and studs will hold up the existing structure. When you open up the existing structure you can add hangers, Stimson or custom made, to secure this connection but the nails will hold it up easily until you are able to convenciently add the hangers.
Then again, maybe I am not understanding the exact problem. There is no substitution for common sense.
Thanks people. A couple digital pics would help. But here is a sketch in the meantime. Don't worry, I frame better than I draw in wretched Paint!
What I thought I'd have was a standard platform-framed 2nd floor (1/2 floor actually)on the existing house: joist ends nailed to a rim joist, both of which bear on the double top plate of the 1st floor wall. Setting a flush header in this case is pretty easy: all I'd do is bolt the new header to the existing rim from the addition side, set the posts to support the new combined header, set my new joists on hangers bearing on the new header, then tear out wall/ceiling finishes from the inside, slip hangers on the old joists and nail these off to the old rim/new header "sandwich". I could then tear out the existing wall and have a nice, clean opening with a flush ceiling. There's no need to trim the existing joists back in my case, since my foundation wall is 9.5" wide and had brick veneer on it, leaving a nice 5" wide ledge on the foundation wall to land the posts that support these headers(as well as a nice ledge for the 1st floor joists for the addition etc.). I end up with a few inches of wasted space in the addition where the posts go, but that's a small price to pay for having my addition dried in before I start the demo on the inside of the house (which we're living in while all this is going on!)
What I've got now is a bit more complicated to "hang" off the new header as you can see. I'll have to use double hangers because the hangers would need to catch both the joist AND the bottom of the studs nailed to the side of the joists. To get the hangers in place, the existing 1st floor wall would have to come out first to make room for the bottom of the hanger. Even though I've nailed the 1st layer of my new header into the end of each existing joist with four 16D spiral nails and they'd be secure enough without the wall under them, the 2nd floor studs would basically be hanging off the nails driven into the sides of the joists until I got my hangers in there and nailed off.
No worries about the flush header overturning due to the load on its side, because the overturning moment is balanced by the new addition's joists in hangers on the other side. There's no way these headers can fall over sideways, since the new joists will be in place before the existing supporting wall comes out.
I don't fancy tearing off yet more sheathing on the existing house, jacking up the top plate, sawing off the studs and jamming a bottom plate under them in sections because though this would look more conventional it wouldn't make the situation any stronger and it's a lot of work just to make things look more "normal".
I think I might nail some 2x4 blocking in there, in-between the studs, over the tops of the joists, to act as a sort of phony bottom plate for the 2nd floor wall. That'll just add a little more nailing area to keep the studs in the air when the wall plate currently supporting them comes out. Then I'd count on the double hangers to support the studs from there on in.
Whatdayathink? Is it any clearer with the sketch?
MM,
Well, that's a different story.
A pretty straightforward situation, although labor intensive.
I would cut any nails between the joists and Studs, and the top plate. If you use a nail cutting blade on a skilsaw, the kerf is the right size for most Simpsons. (You can get the rest of the nails during demo.) Slip the hangers into the kerf from the outside before setting the header.
The really fun part is nailing the hangers to the header. That looks like an ideal application for a "Peashooter" slide hammer.
After you nail off the hangers, you can add blocking like in this pic.
SamT