Replacing a porcelain steel tub and the ceramic and walls, which are 30+
Undecided on a product from American Standard, which is a material
called Americast with porcelain over it, or an acrylic tub. Cast is out
of the question at this point because of the weight and small area it's
going into. Comments on negative or positive of the two choices would be
The existing walls are regular drywall, no green/blue board and has
never deteriorated. Will be replacing the drywall, however everything I
read says to go with cement board. I've looked at numerous pictures on
the net, and people are still using green and blue board. Is it really
necessary to use cement board?
Definitely use concrete board around the tub area.
If drywall held up it's only because it never got wet.
30 years ago the only options were drywall or plywood.
Drywall would usually get ruined by water and plywood
expands and contracts too much to be a good substrate
for tile. But there wasn't concrete board then. (There
was, of course, always the option of masonry over
metal lathe, but that's a specialty skill that's rarely
Someone else probably has better advice on the tub.
I prefer the porcelain look and suspect the acrylic
tub will get badly scratched up over time. But the
plastic tubs are popular. If I were you I'd try to find a
friend who put one in some years ago, and make sure it
still looks good, before deciding on the plastic.
| Replacing a porcelain steel tub and the ceramic and walls, which are 30+
| years old.
| Undecided on a product from American Standard, which is a material
| called Americast with porcelain over it, or an acrylic tub. Cast is out
| of the question at this point because of the weight and small area it's
| going into. Comments on negative or positive of the two choices would be
| The existing walls are regular drywall, no green/blue board and has
| never deteriorated. Will be replacing the drywall, however everything I
| read says to go with cement board. I've looked at numerous pictures on
| the net, and people are still using green and blue board. Is it really
| necessary to use cement board?
Do you use the tub? Or do you shower all the time? Last time anyone
took a bath in my hous was over 15 years ago when the grandkids were little.
We had a fiberglass tub and surround and took it out. Now we have a 60"
shower in the palace of the tub and we love it. Bought a 32 x 60 pan
from Swanstone and it replaced the tub and the drain was in the right
position. Ceramic tile walls, glass door, Kohler valves and a Delta
rainhead and handheld. Looks fantastic and we all like it'
Right now I'm in the process of doing the downstairs bath the same way.
The shower has tile to the ceiling, the rest of the room has 5 tiles
high (50") with a 3" trim band and a 3" bullnose on the top.
The shower also has two grab bars. They are a must as you get older.
My wife also uses a seat in the shower and there is plenty of room in it.
Can't speak about "Americast", but anything with the word "Acrylic" in
front of it means that it's made of the same plastic that Plexiglas is
made of, namely polymethyl methacrylate, or "PMMA" for short. PMMA is
great in terms of water resistance, but it's not a very hard plastic,
and would be susceptible to scratches. You're going to have to do the
wall tiling installation after the tub is in place, so ensure you get a
piece of nice thick pile carpeting and place it pile side down in the
tub to protect the plastic.
You should also know that nail polish is acetone, and acetone will
dissolve PMMA. So, wherever anyone is going to be doing their nails,
it's best not to use an Acrylic working surface. Plastic laminate
stands up well to acetone spills, and my understanding is that the
natural rocks like marble and granite do as well.
Here's how to do your tiling:
1. Install new tub, and tub & shower faucet. If you're going to have a
shower, install the shower arm onto lumber that is braced to the studs
so that in future you can twist hard on the shower arm to remove it from
the elbow in the wall without the elbow bouncing all over the place.
The elbow in the wall is called a "wing back elbow" or "shower elbow"
and will have two holes in it for screws to anchor it securely to any
wood bracing behind it.
2. Also install 3/4 inch plywood in the areas where the shower rod ends
will be mounted to the walls. Make sure the front of that plywood is
flush with the adjacent wall studs.
3. Install a proper tile backer board on the wall studs. The most
popular tile backer boards are cement boards like Wonderboard and
Durock, but Georgia Pacific makes a gypsum based ceramic tile backer
board for baths and showers called "Dens-Shield". I've used it on the
walls around a few tub enclosures, and it's as resistant to water as any
cement board, but it's not as strong as most cement boards.
4. Now, paint over your tile backer board with a moisture barrier like
Red Gard. Ceramic tiling is not impermeable to water, and the moisture
that passes through the porous cement based grout can accumulate in the
wall and support the growth of mold or mildew inside the wall. A
moisture barrier like Red Gard effectively prevents the passage of
moisture through the tiled walls.
Now, do your ceramic tiling. I've set more than my fair share of wall
tiles, and I can tell you the following:
A) It's a bad idea to start your bottom row of tiles on the tub. If the
tub isn't flat and level, then all your tiling will be crooked too.
Instead, fasten straight piece of wood (like pieces of wooden molding)
around the tub enclosure a little way above the tub and going around all
three walls around the tub. Set your first course of tiles on that
wooden molding, and tile up to the ceiling. Then, remove the wooden
molding strips, and cut your bottom row of tile to fit down to the tub.
You want those wood molding strips to be installed so that you have to
cut as little as possible off that last row of tiles that fits down to
the tub. That way, it just looks like the bottom row are full tiles,
but they're not. The advantage of doing it this way is that no matter
how out of whack your tub is, your tiling will still be straight.
B) If you're going to grout, then you have to choose between an epoxy
grout and a portland cement based grout. Epoxy grouts never mildew, but
they're inherently harder to work with. Portland cement based grouts
are much easier to work with, but they need to be sealed in order to
prevent mildew from growing on them in time. If you opt for a portland
cement based grout, then you have two choices: to use a penetrating
grout sealer or a film forming grout sealer. Penetrating grout sealers
theoretically last very much longer than film forming grout sealers. In
my own case, I use a film forming grout sealer on the 21 bathrooms in my
apartment block. If you decide to use a film forming grout sealer, make
sure it says that it's an ACRYLIC grout sealer. There are also silicone
based film forming grout sealers, and the problem with them is that once
they're cured, you can't apply more grout sealer over them to increase
the protection of the grout. That's because nothing sticks well to
silicone based plastics, not even another silicone based plastic. So,
any grout sealer that says "something siloxane" on the bottle will be a
silicone based grout sealer, and if it's meant to just remain on the
surface of the grout, you shouldn't use it. Use an acrylic grout sealer
instead which will allow you to continue adding coats of grout sealer to
the grout lines as the tiling gets older.
C) Do all your tiling first, and then stick your soap dishes and corner
shelves to the tiling. Recessed soap dishes are notorious for being the
cause of leaks into the wall. Better to have the soap dish stuck to the
tiling with silicone caulk so that there's no way water can leak in
around that soap dish. In my building, I have about 25 or more soap
dishes and corner shelves installed that way in 21 bathrooms, and not a
single soap dish or corner shelf has come off in over 25 years now.
I replaced an enameled steel tub with Americast about 25 years ago.
Still looks new, although you have to be careful not to use any
abrasive cleansers. Use cement board if the shower is going to be used
to any degree. That the drywall held up for you would seem to indicate
more baths than showers.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.