"Wing wall" stability; absence of support at one corner
I am rebuilding an interior shower in the same space as the old one, but as a “no curb” -- by raising and appropriately sloping the floor throughout the remainder of the room and tiling the floor and walls outside of the shower area as well as inside. The shower “stall” space is rectangular, approx. 30” x 54”, and is framed in by typical 2x4 construction on three sides, tied to a typical concrete footing and 4” concrete slab (warm climate). I want the side facing the room (54” opening) to be only partially enclosed with a “wing wall” – alongside the showerhead, taking up about ˝ of the opening (i.e. approx. 27” wide). If I can construct this “wing wall” with adequate stability, it will be only 7’ tall and will be attached to the studs at the showerhead (left) end and to the floor, but not to the ceiling. Of course, I would like this “wing wall” itself to be as narrow as possible providing maximum width to the shower area itself for showering.
I realize the standard method of construction would be to have the top/right corner of this wall connected either to the ceiling joists above or to an opposite wall. I am looking for the best method to avoid either of these two options, if possible, simply from the standpoint of aesthetics.
I have considered two alternate methods of building the wall: a) using 4” wide (4”x8”x16”) hollow tile (CMU) with appropriately anchored, 5/8” (or larger) rebar – epoxied into holes drilled 4” into the slab -- from the floor up to the 4’ level with 2x4 framing 3’ on top of that, including framing for a “shampoo shelf”, and b) build the entire wall section with 2x4 framing anchoring it with a vertically placed 2” galvanized pipe sunk into a foot of concrete below the slab and running all the way up (7’) to the top 2x4 rail. (The latter (b) would require hammering/chiseling out a hole in the slab and, in effect, pouring a “footing” for the pipe. For the combination CMU/wood method (a), I would anchor a 7’ long 2x4 to the end of the 4’ high CMU block portion to provide the needed stiffness for the remaining 3’ above the CMU portion.)
I hope my description is clear. I am not concerned that either of these methods will produce a wall that will topple in the wind. However, I would not want someone who loses his or her balance to fall into the wall and have it topple over. Any opinions as to the stability that either of these methods will provide? Any suggestions for alternatives?
Re: "Wing wall" stability; absence of support at one corner
Whew! I'm already tired, just reading about it.
OK, here's another idea for you to consider. Why not make the stud wall out of either 2x6's or 2x8's. It would give you a wider floor plate. I would buy a box of Red Head anchors that were about 5-6" long, if you can find them. Try Home Depot or if they don't have them, look for the local Hilti dealer in the phone book.
Build your wall and then stand it up, where you want it. Drill holes in the floor plate about 3/4" from the outside edge of the plate. The holes need to be just a little bigger than the anchors, so the anchors will slip through from the top of the plate as it sits on the floor. Make sure you have a large washer at the top, by the nut. Drill the wood holes about every 12-16" apart, staggering them side to side, over the length of the floor plate.
Next, use a masonry bit and drill through the holes in the wood, right into the concrete, so the holes match. Look at the box that the anchors come in to see the recommended size of masonry bit they recommended. USE THAT SIZE ONLY! Any larger and the anchors won't grab the sides of the hole.
Now all you have to do is push the Red Heads through the holes in the plate, down into the holes in the concrete. Make sure the nuts are just sitting on the threads so that most or all of the nut threads are filled. It'll give you room on the threads to screw it down because the threads will start coming up through the nut when you screw it.
Crank down on the nuts and it'll snug the plate down to the floor. I'd use a bead of caulk under the floor plate too since you're working with water. I'd also use a pressure treated floor plate too. That should make the wall pretty rigid. No guarantees but that's what I'd do.