master bath project

[Vince]

Hi guys! Been lurking around in here for awhile checkin out some of the posts and I 've got some questions about my bath remodel.
I checked out the deflect-O-lator to see if my floor will support tile and it gave me a thumbs up for ceramic tile. Specs, just in case any injuneers out there want to communt, 2x6 joists of unknown wood type with 6.5 feet between post supports and a beam runing perpindeculr at nine feet. Bath is about 9x10. I currently have 5/8 plywood subfloor covered with vinyl or linoleum of some sort and had carpet which has been torn up already. The shower was previously tile with ceramic which is also torn out now.
My first ? is whether my foundation and subfloor are adequate to support 16x16 travertine with 6x6 porcelin tiles patterned. I'm on top of a crwl space (no basements out here in so cal ) if it makes a difference.
Second ? -- The vinyl flooring that is currently in there is completely stuck. I've tried pulling up a corner and it doesn't buge. Should I try to remove the vinyl before laying CBU?
Additional info---I'm hoping not to have to add to much more height to the floor because my toilet flange is sitting .5 inhes from the floor.
Any input or suggestions would be much appreciated.------Vince

[bbcamp]

Welcome, Vince!

If you joists run the 6 foot direction, they are good for stone or tile. If they run the 9 foot direction, they need help.

Stone floors need double wood, or about 1 1/8" total, or better. You will need to add another 5/8" layer of plywood. If you could live with all ceramic tiles, then 5/8" is the bare minimum, and you would need 1/2" backerboard.

The vinyl needs to come up, if it is cushioned. Most vinyl floors of the 80's and 90's was. However, with the new plywood and backerboard you'll be adding, it may not have to be completely removed. Let's see what the pros have to say.

Your toilet flange can be extended to bring it up to where it needs to be. Do a web search on "flange extenders."

Bob

[Vince]

Thanks for the reply Bob. The joists are supported by posts every 6.5 feet or so. Any ideas on how to beef up the joists? I can't imagine trying to bring a bunch of materials into my tiny crawl space to do repairs. I'll have to look into the extenders for the toilet flange. I really don't want to pay the plumber for another visit unless absolutely necessary.

Vince

[bbcamp]

If the joists are only 6.5 feet long, they don't need support..

If they span 9 feet, then you have to add anther support beam. It needs to go about half way between the wall and the existing beam. Actually, that requires the least material, but it does mean digging a footer for each support post. In crawl spaces that can be difficult. You have to get to undisturbed soil, rock or below frost line. You then fill the hole with concrete, and set a post anchor. Look at the type of materials used for the existing beam, and copy that.

Sometimes we suggest sistering the joists. In your case, that won't work for stone floors, but will work if you switch to ceramic tiles.

[John Bridge]

Welcome aboard, Vince.

[golfin]

Here is a link to what the flange extensions will look like. You should be able to get them at a big box store lowes or HD I have seen them there or support your local plumbing supply store and ask for Closet Flange Extension. Use silicone between the extensions and flange do not use the caulk that comes in the package if it is sold in a kit. Use silicone it is the best way to get the proper seal.


http://www.jtecprod.com/extension.html

[Vince]

Well, I took a break to do some research and tear up the kitchen a little before continuiing with the bathroom. I looked at the liberry and read up on shower pans and the like. I have John and Michael's books on setting tile which I have read a lot of. I've made the executive decision to tear out the plywood (which will remove my vinyl as an extra bonus), build some extra posts to support my joists to cut down my span, lower the floor according to John's book and install 3/4 inch ply between the joists. I am also under the impression that I'm going to need anoother layer of 5/8 plywood on top? The guy at Lowe's is telling me that I should skip the 5/8 ply and just add 1/2 inch hardi and then tile. Any sugguestions?

[cx]

Best not to be advised by the guy at Lowe's, especially if you're still planning to use a natural stone tile. Technically, you wouldn't need the full 5/8ths inch ply, but given the method you're using for the subfloor, I wouldn't use anything less than that. You have final floor height problems? Other than the toilet flange, which is an easy fix. I guess I'm also assuming you have 16 inch joist spacing - don't see it in your first post.

And don't be tempted to rip your sheets of ply in the 8 foot direction. Cross cut it and lay it such that the face grain is perpendicular to the joists, just as you would if you were laying full sheets on top of the joists. And I strongly recommend glue and screws for attachment of both the cleats and subfloor pieces in that kind of construction.

My opinion; worth price charged.

[Vince]

I do have 16 o.c. joist spacing. I'm still usin 16x16 travertine. Lowering the floor takes care of any height problems with the toilet flange. I'm also wondering if I should 1/4 or 1/2 inch hardi and what kind of fasteners should I attach it with? I was also wondering what I use to glue the 5/8 ply to the 3/4 phy? I'm planning to begin work on Wed., so any other suggestions on how I can make my floor 100% flex proof would be appreciated.

[Vince]

I haven't heard anything from anyone, so I went ahead and did the subfloor. I glued and screwed (nailed) 2x4's to the 2x6 joists and then cut the 3/4 ply in the 4 foot direction so the grain runs perpendicular to the joists and glued and screwed that to the cleats. I also added some concrete footers with beams to cut my joist span to 4 feet. I then glued and screwed 5/8 ply to the 3/4 running that perpendicular to the 3/4 ply. I left gaps in between sheets and around the perimeter at least 1/8 in. I put the nails at least every 12 in. Anyone see any problems with this before I move on to installing my hardi board?

[bbcamp]

If I read that right, the 5/8" plywood runs parallel to the joists. If so, you won't get the full benefit. Fortunately, the plywood span is reduced by the thickness of the cleats. If you had the height, another layer of 3/8" plywood running perpendicular to the joists will solve the problem for sure.

[cx]

Sorry Vince, guess you got lost there for a while. Looks like you got it done, though. Bob's right, of course, you should have run that second layer of ply perpendicular to the joists. I think you're OK, though. For future reference, 12 inch fastener spacing for subfloor work is pretty wide. Usually want no more than six inches at the ends and 8 in the field. Again, if you glued it, you're fine.

I think you're ready for your CBU.

[Vince]

Sorry about the confusion with the perpendicularity (a word?) thing. I put the 3/4 ply that is between the joists perpendicular to the joists and the 5/8 ply on top parallel. It sounds like I'm O.K. from the repliles, but I just wanted to clarify. Actually, I'm really glad that I took the advice of the deflecto and everyone else about adding the extra support. My floor feels really solid. I think I might be able to park the truck on it if needed.

Anyways, I'm going to put the mud in the shower this weekend and was wondering if I should mix it with water or an additive? I forget now where I heard to mix it with an additive and why the source said it was necessary, but I want to be sure I do it right. So many questions! I reallly appreciate everyone's replies and knowledge .

[Vince]

I almost forgot. My shower is about 3x5 with the drain in the middle, and I was wondering if I use the slope calculation for the 5 foot span for the 3 foot span also. I'm kinda confused about this slope stuff.

[John Bridge]

Hi Vince,

I figure the slope from the five foot direction, which would give you about 2-1/2 feet from the wall to a central drain. That gives you 5/8 in. in drop from wall to drain. The slope to the closer walls will be steeper, but that's okay. Just keep the perimeter level all the way around.