Tile from that era was done on a thick mud bed instead of with modern thin set methods. And while many bathrooms from that era or even earlier still survive with no moisture damage behind the walls, not all installations were that good. Those have mostly been torn out. Cementitious products are porous. Water pentrates the grout and into the mud. It was just such a thick layer of mud that it didn't usually penetrate all the way through to the wood framing surround it. That's if it was done correctly. If it wasn't, or there was damage to it, then you had just as much moisture damage from that as you would from any modern installation that went wrong.

A good install is a good install, no matter if the method is old or new. And a hack is still a hack.

Yup. You have the most potential for a durable installation when using a true mud bed on the floor and floated mud on the walls. But I've seen those fall apart too. There is good and bad to all methods. But most good and bad has to do with the installer. Material and method "shortcuts" can be the killer to any installation.

For residential, mud bed installations are the minority now. Lightweight construction (true cement board over wood frame) with a topical membrane will give you excellent performance and durability.

A personal choice, but I avoid the latest-greatest eco- and back-friendly tile backer boards and still use plain ole cement board; durock or wonderboard.

It's almost been 20 years (gulp) since I've gone completely over to topical membranes, which one depends on if I simply need waterproofing or if I also need a vapor barrier for a steam shower.

Use a proper thinset and avoid mastics in showers.

Use proper moisture ventilation. Don't scrimp on the fan. Or the ductwork. And use a timer switch for the fan.

In the olden days when houses leaked air like heck, moisture vapor control was less of an issue as air movement through the envelope simply whisked moisture away. An oversimplification for sure, but my point is that with today's tighter thermal envelopes, moisture control is more critical today than it was 50 or even 30 years ago.

Fantastic question/topic. Mongo, you say that you use plain ole cement board. What do you use for the shower floor typically? Do you do build one with mud and apply a topical membrane over top? Or do you use some of the new pre-formed products such as the Schluter shower tray?

Would love to hear more as well.

Here in Southern California, the mud method is still king. Every single GC, plumber, electrician, tiler - basically every tradesman I spoke to before choosing my team preferred mud. My main contractor tore out the old tile, which was mudded, and showed it to me and said "make sure the tiler you choose does this method because it will last forever." So I am mudding! (Mind you none of these fellows are under forty years old!)

I personally don't care, as the other posters said, you can have bad installs using any method. I would defer to the contractor you choose as to the method they are experienced and comfortable with.

The mud method does seem to be going away with the old timers, and some of them say that the new products were born out of necessity - having a lot of housing developments built in the good times and not enough experienced tradespeople - so easier/quicker methods were introduced.

Forgot to add that the new methods are much more user-friendly for DIY homeowners, a group that has grown by leaps and bounds with the advent of cable TV DIY shows and spurred along by the real estate boom.

When remodeling my kitchen I joined the tile setters forum so that they could give my tile guy instructions on "how to do the same kind of tile installation my mother has." (She's 98.--house was built in 1954. Perfect, absolutely perfect tile.) The mud base was the reason for tile's longevity--but also, because you can mud up or down a wall as if it is one piece, you can avoid using caulk, and just grout or use those curved pieces instead of 90o angles at the bases/baseboards, or from countertops up the wall. Looks so clean, and it has such a substantial "feel" to it.

"What do you use for the shower floor typically? Do you do build one with mud and apply a topical membrane over top? Or do you use some of the new pre-formed products such as the Schluter shower tray?"

Yes, mostly every shower floor I have done in recent years is a deck mud base with a topical membrane over it.

Quite a few years ago I converted a warehouse building into apartments. I had 11 bathrooms showers to do, I used Schluter's Kerdi Trays. No regrets using them.

But given the choice of using one over the other, while there are advantages to the manufactured pans, I'd pick a mud bed every day of the week. You can make the size, the shape, the slope...pretty much whatever you need.

Thanks for the feedback. Good to know that the Schluter trays work well and that mud bed can be preferable due to the options it offers. My master shower area seems like it has maybe an odd size that I'll need to account for, so I've been thinking mud bed is probably the way to go. I really liked using Ditra for several floor installations, so I'm hoping I'll like using Kerdi for waterproofing a shower as well.