Cob: cleaning earth plaster

[Steve Lewis]

What i do is trowel my clay/lime finish plaster to a smooth finish.
Polished it, really.

 Then, for washability, and to control stain uptake, I give it two coats of
acrylic masonary (or tile) sealer.   Superdeck has a good one, "mason's
select"

Acrylic sealer is like clear latex paint, but really better.  It's got great
coverage  ($20 worth for two rooms)  the matte finish version is not too
shiny,  it is nearly odorless,  water resistant, washable, yet it does
breathe, much better, it seems than latex paint.  Companies for the
chemically sensitive sell similar products  at a higher price.

I have heard that "Future",  an acrylic floor finish sold in groceries, is
similar as well.  Have not tried it.

It needs to be renewed every few years, by recoating.  Very simple solution.

Steve L