Getting ready for the bathroom subfloor project scheduled for this weekend...

tallycat77

First-thanks to everyone who has so generously offered their advice in a previous post (perhaps I should have psoted there???). In preparation for my project, I have discovered and learned a lot about my floor. I have 2x12 floor trusses (2x4's that are bridged togther with metal V straps and that sit 12" apart) these are 24"OC. The bathroom wall runs parallel to the trusses and sits in between, one about 4" into the bathroom and the other in the kitchen. How am I to patch this portion that is in between joists?:confused: I was advised to replace the whole floor and then somebody else told me that was not a good idea, if it wasn't necessary. Can I use blocking in between with a floor truss system? I don't know how to tell if this is a load bearing wall or not. There is an upstairs bedroom and bath and this wall runs half the length, about 6' in. I have to take care of this ASAP and any advice on repairing a subfloor under these conditions is appreciated. Also, I have gotten mixed reviews about installing tile with hardi-backer board in this area with the trusses being 24"OC. Any advice?:o

floorman

First, sorry it took so long to get a reply to ya.

The wall that you refer to is more than likely Not load bearing wall but to make sure go downstairs and look to see where the beam is,that would be the piece of steel that runs the length of the house and try to envision where that wall is in comparison to that beam,if it does not run ontop of that beam or across it then it is not load bearing.Now weather is or not does not really matter to what your floor is going to do or not do.Unless it is a mile or so away from the beam,meaning the closer to the beam you are then the better off you are.
Now ,how thick is the subfloor?Remove a vent in the floor and get a tape and see what it is.If 3/4 o.s.b. or plywood then you should be o.k.if particle wood then it will have to go.If you have an area that has no bracing then you will ahve to figure out how to get some in there to support the portion at the wall that has no joist under it,if you have to replace the subfloor,if not then leave it alone as the sheet is already attached to a joist on the other side of the wall.

I'm not a fan of hardibacker but alot of people are,my first choice is durock but that is my preference.I would use 1/2 backerboard whatever it is install that to the manfacturers reccomendations.
Let us know if we can help some more

tallycat77

Floorman-no problem about the delay, but I am getting a bit "antsy"...
First, I doubt this is a load bearing wall, because I can see under it (from the hole in the floor...) and there is no steel, It rests only on the subfloor and it is in between joists/trusses. I don't really know how to find where this steel beam is. However, I don't think it can be far, I am in a small townhouse and the bathroom is about in the center. My guess it is about 6' as I suspect the load bearing wall is the one in the front of the kitchen that runs all the way up to the 2nd floor. (Upstairs bed and bath sit at the back of the house). I also measured through the hole and the subfloor is at least 1", if not 1 1/8" or 1 1/4". It is plywood and not particle board. It appears someone has done some kind of repair in the past, in the kitchen on the other side of the wall, because I can feel a 2x4 screwed into the subfloor from below, i guess for the additional support.
Is there anyway that after I get this hole patched and the wax ring replaced that I can use durarock and then tile? I have been reading and reading and get mixed answers. It's a small room, the 12" trusses are 24" OC. At this point, even though I think tile would be nice, I will just be happy to have that hole patched and my floor back together. I just won't be using the peel n stick tiles.

floorman

Are you looking at bare plywood now?Is there any type of flooring on the floor now?If not i would put 1/2 durock on the floor and then tile it if there is a floor there now you would either want to remove it or at least get the floor flat and maybe use 1/4 rock over that but i would want to know what that floor is before i commit to telling you to do that.
So get back to us and let us know what you have

Benhamcarpetguy

For 24"OC wouldn't they need more plywood before the CBB? I know it's a small bathroom but... wouldn't 3/4" plywood bring it to spec? I'm looking at an old TCA book but isn't Durock a non-option with a double layer of plywood anyway?

Don

tallycat77

Foorman-There are currently peel n stick tiles down. I have pulled one up that is over the hole. Underneath there is plywood, best measurment I could get from the hole says it is 1" thick, could be 1 1/8".

housedocs

1-1/8" subfloor is what's called for in the specs, but those peel and stick tiles need to go for sure, not suitable substrate. I'm also a durock fan myself, but if you've got a height issue you could use ditra set in thinset over the 1-1/8" of plywood, double 5/8" good grade material is what I'd use, it's a small room as was pointed out, why take a chance on setting tile over a questionable subfloor. Rip it all out, come back with two layers of 5/8" plywood, glued & screwed down, then thinset & either durock or ditra & you're ready to lay the floor.

__________________
All you need is ignorance and confidence and success is assured. - Mark Twain

floorman

Sweet

patticake

I have a similar situation, but hopefully not nearly as severe or involved. In my bathroom I have 4 -1/4 " tile installed over a plywood subfloor..(Was this the "standard" in condo construction in the 80's?) I definitley have water damage from "someone"... (no names of guilty parties!) recently repeatedly forgetting to check the shower curtain liner to prevent this. I did manage to pull up the corner tiles and did find the wood was damp, dark, damaged, and smelly. I still have to get at least 3 or 4 more tiles up along the tub, but so far at the worst point in the corner it only seems to extend out about 5 inches. I also removed a few of the baseboard tiles and there is extremely minimal damage or staining to the sheetrock. Back to the flooring, I scraped up the rotted wood and then used straight bleach on it and dried it with my hairdryer.(hey, I'm a girl...what do I know???? , but it seemed to work!!!!) The sub floor definitley came back to it's natural color, but it is still (1 day later), just a hair damp, with only a very slight odor. Nothing ever seemed "mushy or spongy" with the floor. Do i really need to get so involved with replacing the sub floor section..or can I give it more time exposed to dry, and then use some type of sealer or barrier to protect it before I re-adhere the tiles?
I'll also mention that I'm a 3rd floor, one level, unit, and fortunatley haven't had any complaints of ceiling damage from the downstairs neighbor (thank goodness!!!!)
I was also wondering ...is there a good product to clean the old grout and adhesive from the old tiles?
As you can probably guess, it gets "fixed" by me, or I need to hire someone. I'm really hope this need not be a huge and costly project as I just splurged on new carpet, laminate flooring and tile for all the rest of the place!
Also, this is my first post to any type of forum/chat/or advice, so excuse me if I was too lengthy or didn't follow proper "etiquette". I really need some advice and got nowhere today after wasting over an hour in "H.D." and searching countless other web sites with no clear cut answers or solutions!
Thanks for any replies!!!!!!