Bath Remodel Help

metron · #1 09-09-2010, 10:40 AM

Im doing a complete rebuild in my bathroom and I have a problem. What better place to get construction help than TB OT?!

The original subfloor is 1/2" osb and is pretty brittle so I am removing it completely to the edge of the walls. What I have run into is that the walls that are parallel to the floor joists are not directly supported by the joists, they sit between joists and there is no additional support below. Clearly I can't just leave them hanging there so my question is what is a proper fix that meets typical code to support the wall and floor joint? I can access the floor from below.

Jim Campbell · #2 09-09-2010, 10:43 AM

Quote:

Originally Posted by metron

Im doing a complete rebuild in my bathroom and I have a problem. What better place to get construction help than TB OT?!

The original subfloor is 1/2" osb and is pretty brittle so I am removing it completely to the edge of the walls. What I have run into is that the walls that are parallel to the floor joists are not directly supported by the joists, they sit between joists and there is no additional support below. Clearly I can't just leave them hanging there so my question is what is a proper fix that meets typical code to support the wall and floor joint? I can access the floor from below.

depends if those are load bearing walls or not......load bearing walls will usually run across the joists and not parallel

metron · #3 09-09-2010, 11:20 AM

They are almost definitely not load bearing walls. I'm primarily worried about sagging walls and that there will be a floor joint between joists at the entrance to the room.

becker4567 · #4 09-09-2010, 11:52 AM

Can you get under the house? If so the answer is a few pier block supports under the walls. If you can't get under, don't take the floor out right up to the walls. Cut the floor out directly over (splitting) the floor joists.

hover · #5 09-09-2010, 12:12 PM

put some support boards from joist to joist underneath the non-load-bearing wall in question, every 16" or so... It will support the wall more than the subflooring ever did, and strengthen the structure around it / keep the joists in place.

There should be braces like this throughout the structure anyway, to keep the joists aligned and prevent twisting.

()smoke() · #6 09-09-2010, 12:46 PM

are you certain you have 1/2" osb as a sub floor material? what is the spacing of your floor joists?

metron · #7 09-09-2010, 01:06 PM

I forgot to mention this is on the first floor and there is a basement. I can get under it by taking out some drop ceiling in the basement.

It's definitely 1/2" osb (house was built in 1963). The problem with leaving part of it in around the edges is that a new 3/4" subfloor is going in so I pretty much have to cut it all out.

The joist spacing is I believe 16" through most of the house. From what I can see, there is only bracing under larger spans of floor like under my dining room and that may not even be original. Oddly part of the joist spacing in the center of the bathroom looks like it's at least 24"

I will need to add support to that as well.

I figured that the solution would be blocking or bracing between the joists. Is one option better than another? Lumber cost is not a factor.

Thanks for the tips fellow bassists!

Ben B · #8 09-09-2010, 01:24 PM

Quote:

Originally Posted by metron

I figured that the solution would be blocking or bracing between the joists.

That's what I'd do. I'd get lumber of the same size as the existing joists (2x10?) and connect the cross braces to the joists with metal joist hangers.

Ben

hover · #9 09-09-2010, 01:52 PM

yeah, brace in place through the studs on each side, then add the joist hangers for just that bit more support...when you pop the new sub-floor in, make sure to FILL the entire seam around it and the existing wall with black phenoseal to keep any moisture from wicking into that area and causing potential mold problems....let it cure 24-48, then plop down your flooring or tile or what have you.

metron · #10 09-09-2010, 03:07 PM

Quote:

Originally Posted by Ben B

That's what I'd do. I'd get lumber of the same size as the existing joists (2x10?) and connect the cross braces to the joists with metal joist hangers.

Ben

I might be confused on terminology. Cross bracing is literally an X between joists right? How would you use the hangers on an X cross brace arrangement? Or are you suggesting vertically oriented pieces of 2x10 perpendicular to the joists? Thats what I guessed I would be doing.

Quote:

Originally Posted by hover

yeah, brace in place through the studs on each side, then add the joist hangers for just that bit more support...when you pop the new sub-floor in, make sure to FILL the entire seam around it and the existing wall with black phenoseal to keep any moisture from wicking into that area and causing potential mold problems....let it cure 24-48, then plop down your flooring or tile or what have you.

Will do, thanks for the tip!

iamlowsound · #11 09-09-2010, 06:25 PM

Quote:

Originally Posted by metron

I might be confused on terminology. Cross bracing is literally an X between joists right? How would you use the hangers on an X cross brace arrangement? Or are you suggesting vertically oriented pieces of 2x10 perpendicular to the joists? Thats what I guessed I would be doing.

Will do, thanks for the tip!

No cross bracing, do the 2x10 thing. Former (sometimes current) carpenter speaking.

lowsound

Jim Campbell · #12 09-09-2010, 06:34 PM

Quote:

Originally Posted by metron

Im doing a complete rebuild in my bathroom and I have a problem. What better place to get construction help than TB OT?!

The original subfloor is 1/2" osb and is pretty brittle so I am removing it completely to the edge of the walls. What I have run into is that the walls that are parallel to the floor joists are not directly supported by the joists, they sit between joists and there is no additional support below. Clearly I can't just leave them hanging there so my question is what is a proper fix that meets typical code to support the wall and floor joint? I can access the floor from below.

what leads you to believe that the floor will not carry the weight.....has it not done so since it was built....a non load bearing wall running parallel to the joist is not usually a problem.....is it feasible to add a tele-post downstairs to span a few joists.....a pic or three might be a good idea...

metron · #13 09-10-2010, 08:48 AM

Quote:

Originally Posted by iamlowsound

No cross bracing, do the 2x10 thing. Former (sometimes current) carpenter speaking.

lowsound

Gotcha thanks!

Quote:

Originally Posted by Jim Campbell

what leads you to believe that the floor will not carry the weight.....has it not done so since it was built....a non load bearing wall running parallel to the joist is not usually a problem.....is it feasible to add a tele-post downstairs to span a few joists.....a pic or three might be a good idea...

Well once I cut the sub floor out to the edges of the room, the portions of it that remain under the walls will only have support from one side, in the adjacent room. Judging from the strength of the subfloor in it's old dried condition, I am treating the situation as though the walls have little to no support. Also the entrance to the bath is at the same wall and will have an unsupported floor joint. That will definitely sag over time. I would rather take care of the whole thing while I am doing the job and never worry about it again.

Thanks again for the advice everyone!

iamlowsound · #14 09-10-2010, 10:02 AM

No problem. TBOT is here to help. I am continually amazed at how badly people do things, good on you for wanting to do it correctly.

lowsound

Ben B · #15 09-10-2010, 12:12 PM

Quote:

Originally Posted by metron

I might be confused on terminology. Cross bracing is literally an X between joists right? How would you use the hangers on an X cross brace arrangement? Or are you suggesting vertically oriented pieces of 2x10 perpendicular to the joists? Thats what I guessed I would be doing.

Will do, thanks for the tip!

Sorry for the confusion on the terminology. Yes, I meant run pieces of 2x10 perpendicular to the joists.

Ben