Tadelakt is NOT a DIY project it is very high $$$$ also requires some high class rubbing rocks.
here are some other products I saw mentioned in some plaster videos.
I don't think Tadelakt falls into the DIY category since it involved 4 separate layers and maybe 5 coats expertly applied, but the black soap might be the approach I use instead of paint. I already have a plaster over the wall so maybe black soap applied to the existing plaster will penetrate and waterproof it.
The dream bathroom would be a walk-in tadelakt shower but the bathroom I want for the near future is a $65 glue up shower wall.
As to the question of how long Plaster will last.I have a habit of either procrastinating forever or finishing a job as fast as possible but a little sloppy. I chose the latter for this project.
I mixed mortar with the plaster around the rocks.
then I mixed plaster of paris powder with the limewash.
I also used concrete bonding agent with both and that helped it all stick. of course scraping and washing the walls was important since there was old latex paint on the old plaster. I did experiment with car wax to see if it reduces the amount of chalk that rubs off the lime wash.
I'm going to let nature take its course before I do any more work on these walls. I need some idea of how long lime plaster really lasts. If it stays like this I will be satisfied.
I think my options for an interior earth wall are limited to custom lime plaster but I think the original plaster is some kind of structo-lite plaster basecoat with a veneer coat. I did identify lime in the original plaster by putting vinegar on it, but it looks so uniform I think it was from a bag. It might even be the same basecoat they used for the exterior.
It failed mostly because the roof leaked badly for years and the plaster is 80 years old with no lath.
I would definitely experiment with structo-lite or a stucco base coat if I didn't want to custom mix lime and sand.
thanks for the help.
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