This one is old school and built like a tornado shelter...3/8" expanded, no ribs. You wonder why the old timers didn't run felt behind the lath if they weren't using ribbed...seems like a lot of mud to waste.

And certainly before the thinset era...they just made there own.

The wet bed mix is the usual course sand type, I would would guess 4 to 1 or more, the setting layer, super thin with fine sand, I would guess 1 to 1 using white cement.

Anybody know for sure the setting layer mix that was common back in the day...even this mud man can only speculate and there not many guys left to ask.

I wonder in what years this bathroom was built? I saw this last time at my great-grandmother, who lived in Utah and unfortunately died a couple of years ago. With these photos, you reminded me about her house, which was very cozy and comfortable even though the whole place was old. The only thing we changed in her home was that we bought special mattresses for our great-grandmother's restful sleep, and we did it thanks to a website that I accidentally came across this site https://bedselection.co.uk/. I have never seen such a detailed description of the choice of mattress. But you know what, I've always adored old school. There's something magical about that time.