Best way to fix troubled plaster-and-tile bathroom walls
The walls in one of our bathroms are in bad shape, and I’d welcome any suggestions.
Background: House built in 1959, walls are drywall with metal lathe and then plaster.
Problem: The tiles are coming off the walls in one of our bathrooms. The I know I’ve had leaking water behind one of the walls, but the tiles are now coming off far away (many feet) from the leak. The tiles were affixed to the plaster with mastic. The mastic is still stuck to the tiles, and to a thin, hard top coat of the plaster, but this thin, hard plaster top coat is coming off the plaster leaving behind a chalky surface,
The first photo shows the whole area (the area behind the brown tape is where the ceramic soap dish used to be–before it fell out).
The second photo shows a closeup of the mastic affixed to the top coat and the underlying plaster. (The gaping hole is where the soap dish was–I took off the tape)
In addition to the areas where I’ve pulled off the loose tile, it is also loose on much of the right wall (where the towel bar is). In one area (see corner where tub meets wall) the lathe has rusted away and large chunks of the plaster have come loose, revealing the wallboard.
Ideas/Recommendations? It seems to me I could either:
A) Lighlty abrade the plaster until the chalkiness is gone (this seems to work) and then find something that I can apply to it (Thinset? Mastic?) and reset the tiles on the wall.
B) Remove all the tiles and the plaster and the wallboard on the afflicted walls behind the tiles . Apply enough thicknesses/layers of cement board or Hardibacker on the studs to bring things up to the same thickness as the previous wall (so that I can do less patching and filling where the new surface meets an old one.
Of course, Option A would be much less work. If there’s a significant likelihood that it would work, that’s what I’d favor.
“Extra credit”: This wall structure (drywall AND plaster) seems like a short-lived hybrid bridging the gap between traditional lathe-and-plaster and modern drywall. Why were walls ever done like this? We like it a lot, the house is very quiet, and because there’s so much mass on the inside I think the house probably stays cooler longer during summer mornings. Still, it’s got to be a lot more expensive than just using sheetrock and joint compound.
Thanks for any input/suggestions.
Replies
If the tile's been there since 1959 then it's served well beyond what would be expected for a mastic-over-plaster job. You can piss around with patching it, but I'd say rip it out to the studs and redo from scratch -- don't even try to save the side walls.
The materials available now are so much better than what was available then.
PS: Don't forget to protect the tub with cardboard and layers of paper when tearing things out -- pretty easy to wreck a tub when tearing out tile if you don't take precautions.
Extra credit
The reason walls were done like that and continue to be done that way today is that it a reasonable way to approximate plaster without a full blown lath and plaster job. In my opinion, plaster walls are better. There is a "feel" that is unmatched in lesser construction. You just know when you're in an old plaster walled house because of that feel. And your observations are 100% correct, the greater mass is a wonderful addition for temperature moderation and sound deadening.
I had my house done this way. The current practice is to use "blueboard" drywall material (yellowboard in wet areas) and a top coat called "calcoat" that very closley resembles real plaster and gives a much better feel and finish than the exposed paper gypsum wall board so common in construction for the last 50 years. It is more expensive and requires a level of skill beyond that of the average drywaller or DIYer. Putting a smooth, flat surface on a large wall with plaster or calcoat is certainly beyond my skill level and I can drywall and mud acceptably well. At least as good as most new contsruction I've seen. Like almost all things, you get what you pay for. In larger metropolitan areas, I'm sure you could still find skilled plasterers, but not in smaller towns.
Note that what you have may be "rock lath' -- gypsum board in smaller (roughly 16x32, IIRC) pieces, with a rough surface. This was intended as a base for plaster and is still being used in some parts of the country. Goes up really fast (a two-man crew can do a moderate sized house in a day -- though the cleanup takes two days after), and makes a good base for 2-coat plaster.