We are sistering a few 2×10 joists that support our 2nd floor bathroom to help support a cast iron clawfoot tub. We have pulled out the kitchen ceiling below (badly stained anyway) and we see that we can set the ends of the sisters up onto the top plate with the old joists on both ends of the room (spans 13′).
The problem is that old and new 2x10s are not exactly the same width, right? So is it more important that the bottom edge rests even on the top plate with the old joist, or that that top edges are level against the floor up above.
Also, in a couple of places there is a bit of notching near the top that has to happen to help accommodate the tub drain. Should we get these new joists attached before or after the plumber replaces all the old pipe?
Thanks in advance!
Replies
Better to rest the new joists on the plate.
I'd ask the plumber what works best for him/her. But if it were my job, I'd rather fit my new joists around the new plumbing, than let the plumber cut them up.
Putting it diplomatically, plumbers aren't known to be very concerned about framing materials.
Wow.
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Sistering floor joists <!---->[2 new] <!---->
12:26pm
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Sistering floor joists <!---->[1 new] <!---->sistered posts too.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
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sistered posts too.
OK. You answer the other one and give the opposite advice. That'll larn 'em.
Sorry about the double post. I thought I posted it but then I didn't see it there and thought I hadn't followed through and clicked the right button.
Lot of people wanting advice on their sisters all of a sudden!
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Don't have any, but the DW makes up for that, she has 7.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
The world of people goes up and
down and people go up and down with
their world; warriors have no business
following the ups and downs of their
fellow men.
You trying to kill this poor guy?
Its gonna be hard enough sistering these joists without having plumbing in the way too.
The trick is stand over your plumber with a nailgun in hand. When he tries to butcher your new joists "give him a hand".
Family.....They're always there when they need you.
You trying to kill this poor guy?
Its gonna be hard enough sistering these joists without having plumbing in the way too.
HVC: "I'd ask the plumber what works best for him/her."
Remember that part of my post? Maybe the new plumbing won't even pass through the joists. Maybe it'll only be supply lines.
But I like the nailgun suggestion. Probably be better with staples though.
Yeah, I remember, but i've never seen a house plumbed before it was framed either.
Family.....They're always there when they need you.
Make sure you tie the new to the old joists.
Some just nail like 2 nails every 16" on center or so, others use construction adhesive and then nail 3 nails every 8" on center.
I typically glue and nail 3 nails 16" oc which is plenty.
If you set the new joist on the plates, make sure either the new joist does not touch the floor above or glue to the floor above and tie the new joist to the floor above to minimize the squeeking.
(I would glue and install the joists and shim them up tight to the floor so that the joists are secured to the subfloor cause I HATE squeeks)
It might also be helpful to know what proper drilling and notching methods are. While different localities may have somewhat different rules a quick Google brought up this document. Look at figure 7 on sheet 7.
I'm not a remodeler but personally my plan of attack would be 1) remove the pipes that are to be replaced. 2) sister joists with shimming at the top plates and nailing and gluing as described above. 3) Get the plumber in there and cover his plan with him for drilling/etc the new joists before he actually does it - just to make sure. Like maybe just ask him to mark on the joists with a pencil where the new pipe will be. He may get a little huffy, but my experience with plumbers is they always say sorry when they F-up your joists but don't usually actually make the repair. Even if they do they will probably be quick to point out that glue (or whatever) isn't necessary.
If some of the existing joists are notched improperly, I think (after removing the old pipe) I'd ignore the wrong stuff and have the new pipes put in the correct locations on the new joists. As often as not notching and DWV don't really go together unless the floor joists are 2x12 and even that is touch and go.
You shouldn't need to sister all the joists.
Your cast-iron claw-footed tub only pushes on the floor at four places; if you insert two built-up joists--say, tripled 2x8s--so that each runs directly under two of the tub's feet, you should be fine on the support issue. It would be even better if you put some columnar support (tripled studs, for instance) directly under where those built-up joists rest on the plates.
By using a shorter depth of joist and tripling it up, you will leave enough room to run a 1½" ABS DWV line under it without notching.
Assemble the built-up joists with PL Premium and through-bolts (not lag screws) zig-zag patterned on 16" centers. (Once the glue dries, you can take out the bolts if you want to.)
Install the joists using screw-post jacks to get them up tight to the floor. Run a bead of PL Premium on top of the joists before you install them. Set them in position and jack up with the screw-posts. You should actually raise the bathroom floor an eighth inch or so while jacking. Shim snug between the joist heels and the plates, and lower the joists onto the shims. The floor will come back to its former plane as the shims compress.
(PS--this assumes you do not have existing ceramic tile on the bathroom floor that you wish to preserve intact.)
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Thanks for the clear advice, and sorry about the "sistered" post!
Good luck.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....