Replies

1. 
   david_thodal | Feb 26, 2002 11:15pm | #1

   *
   Timothy, One way is to cut out the sheetrock from 1/2" below the top edge of your wainscott to the floor and fill in with 5/8cdx. Tape the joint. Then you have solid nailing for all your wainscott details.

   Alternately you can simply glue and nail whatever thickness you can accept of plywood, either strips or full sheet over the drywall. Minimum thickness would be 1/4". This gives nailpurchase for your wainscott.

   Another choice is to glue thw wainscott directly to the drywall using a good quality construction adhesive or urethane adhesive. You can blindnail into the drywall with brads to hold the wainscott in place until the adhesive sets.

   My personal choice would be the first suggestion, but all will work.

   walk good

   david

1. 
   calvin_ | Feb 26, 2002 11:31pm | #2

   *For the sort of look you are trying to achieve (using solid wood bds) might be new v-groove barn siding. It'll have knots you'll have to deal with as far as finish. There are 3/8" packaged pcs of pine beadbd too, some primed, some not. The paneling is usually the cheapest, but sometimes not the best looking. Stay away from masonite. Look, ask how much, you do the deciding. Whatever you do, prime all sides before install and maybe finish paint the tongues. You won't like it if you don't, when it shrinks.

1. 
   Mongo_ | Feb 27, 2002 01:37am | #3

   *Good suggestions.If you use 3/8th inch beadboard, you can mill a 3/8ths inch rabbet in the top of the 3/4" base and the bottom of the 3/4" cap rail. Install the base, nailing into the studs. Then run your beadboards, one-by-one, tucking them into the rabbet in the base. I'd still run a bead of adhesive on the back of the beadboard. I'd also consider running a small bead of adhesive in the bottom of the rabbet in the baseboard. Once all the boards are in place, run your chair/cap rail, capturing the tops of the beadboard in the rabbet on the chair/cap rail. The rabbet technique gives you a thinner profile, taking up less floor space.If you want more visual depth/shadow lines, consider the following:Simply run the bead board directly on the drywall, using adhesive to tack it to the drywall. Then, over the bottom of the beadboard, mount your baseboard. Nail the base through the beadboard and into the studs. That'll hold the bead snug.Same with the cap...run a chair rail over the upper face of the beadboard with the top of the rail molding flush with the top of the bead board. Nail it off, again, through the beadboard and into the studs. Use a flat cap (1x2 or 1x3) to cover the top end grain of the beadboard and the top of the chair rail.Before you come up with a plan, check to see what kind of room you have behind the toilet tank. Sometimes a minimal clearance requires pulling the drywall.If my words don't make sense and you need a pic, let me know.

1. 
   tom_varney | Mar 02, 2002 02:31am | #4

   *I recently did a job with 5/16 paneling that looked like beadboard. I nailed the paneling to te studs and also glued it with liquid nails. The base and rail was rabbited and the cap was notched over the existing 3/4 trim on the doors and windows. There was no problem with the toilet, but matching it to the stair trim was difficult.

2. 
   TNDonna | Mar 28, 2002 06:38pm | #5

   Hi All,

   This thread is a bit old but my question fits so will give it a try before starting a new one. I'm planning to use T&G beadboard wainscoting in bathrooms in new house under construction. The master bath is the trickiest as it has two exterior walls and the whirlpool tub w/tile surround will be in the corner. Will be insulating with Icynene (spray foam).

   I'm wondering if cdx would be the best thing to use behind the beadboard next to the tub, and if so, should it go all the way to the floor behind tub to provide a continuous air barrier? Or would it be safer to use greenboard instead of plywood and glue the beadboard to that? And am I asking for moisture damage if I run the beadboard all the way down to the tile on the tub deck without installing a tile backspash?

   Also, in the corner opposite the tub there will be a pre-fab shower stall with one end on an outside wall, so if there's enough clearance (will be tight) should I run the greenboard or cdx behind that as well? The GC said he usually just runs the drywall over the top and side flanges but I'd prefer a continuous air barrier behind the shower as well, at least on the exterior wall.

   Many thanks,

   Donna

1. 
   dthodal | Mar 28, 2002 08:03pm | #6

   Using cdx would work fine in your tub installation. Actually it would be an excellent way to deal will the construction. I will typically use cdx on walls where I plan to innstall vertical wainscot, running the sheet to about an 1" of the transition of drywall and wainscott. I will tape the joint as well with hot mud and finish it as if it were a drywall joint. When the wainscott is completed the joint is covered. Using plywood gives excellent nailing without having to resort to adhesives and saves on labour over blocking. I would use 5/8" cdx if using 1/2" rock and float the mud flat.

   As far as your tub area, plywood would be a better choice over drywall as it will soak less moisture than drywall. Before the walls are drywalled, brush on several coats of polyurethane, especially on edges and you will have a very moisture proof substrate. Again use 5/8" cdx and float your butts with drywall flat.

   It would be a good choice to use a tile backslash around the tub, but if you choose not to you could install the wainscott with a few considerations to improve moisture tightness.

   First, regardless of backsplash material, run your waterproofing which goes on under the tile up the wall (cdx) about 12". Pay special attention to the joint between tub and wall. When the tile is being set on the tub surface slope the tile so it drains from the wall to the tub. This should be from every wall . About 1/8" per foot is sufficent. If you bring your wainscott down to the tile surface, you will want to grout with a good water tight caulk the edge of the tile against the wall. Allow the caulk to be proud of the tile and make sure it fills all the voids and overlapps on the tile a bit.

   Wood end grain absorbs moisture more than edge grain or the face. If possible, I would first run a horizontal trim board maybe 2-3" wide around the tub. This would serve as a backsplash and bottom trim piece of the wainscott. It would not sit tight to the tile, but would run about 1/8" above the tile. This would help minimize any water build-up at the wood by allowing easy drainage ( remember your sloped tile?) . I would rabbit the top edge to fit the matching rabbit of my wainscott board, with the wainscott fitting over the trim. All the would should be well sealed and as added protection, rub the end grain well with butcher's wax or bee's wax.

   I have done several shower/tub enclosures like this will excellent durability. I prefer using a penetrating sealer like WATCO or my own mix to insure optimum moisture sealing. I find a penetrating oil fills the pores of the wood much deeper than a top-coating urethane type sealer. Several coats brushed in well will last a good while. As added insurance/maintainence, I reccommend reapplying a coat every year, especially in a shower application.

   As far as your shower and dry wall, I frame a solid backing for all the flanges of the shower stall and attach the flange directly to that. The drywall is then overlaped the flange. I like using J-bead on my exposed drywall edge and holding the edge back from the shower itself about 3/8". Many builders prefer to run the drywall tight to the shower and caulk that joint. Both ways work. Caulk under your drywall regardless of what technique you use to maintain water tightness.

   Long winded but hopefully helpful

   davidwalk good

2. 
   TNDonna | Mar 28, 2002 10:13pm | #7

   Thanks so much for the tips. (Long-winded answers are the best kind!) I think I'm visualizing what you've described correctly but wanted to clarify two things:

   "will typically use cdx on walls where I plan to innstall vertical wainscot, running the sheet to about an 1" of the transition of drywall and wainscott."

   My question: Do you mean that you stop the cdx 1" below the lower edge of the drywall, or that you butt the cdx and drywall 1" below the transition between drywall and wainscoting? (I suspect you mean the latter but just wanted to be sure)

   Also, when you say you use "a penetrating sealer like WATCO or my own mix to insure optimum moisture sealing" did you mean you use that for sealing the plywood or the beadboard? I'm planning to paint the beadboard but need to use water-based paints/sealers only due to sensitivities to oil-based products.

   Sorry for the persistent questions, but after all the time you spent on your answer I want to make sure I'm not misinterpreting anything!

   Donna

3. 
   dthodal | Mar 28, 2002 11:31pm | #8

   Donna, Always glad to help. Anytime.

   In respose to your first question, the drywall and cdx are butting, 1" below the top edge of your wainscott. Therefore a bit of your wainscott, usually the cap covers drywall which effectively hides your drywall joint.

   If you are planning to paint the wainscott, you can forget the sealer. However I would pay close attention to the edges and ends of your boards as that is where typically moisture will enter. It would not hurt to prime every board first before install. If oil-based finishs are a problem, consider using an alcohol based primer rather than latex.

   Once primed and installed, then you can paint .

   My suggestion with oil sealers is the absorbtion into the pores of the wood rather than lying at the surface. Paint especially can be troublesome with moisture getting into the wood grain and causing the paint to blister or bubble off.

   good luck

   davidwalk good