[Greenbuilding] Ferrous Sulfate concrete floor finish

[Doug Horgan]

I tried Cathy Moore's Ferrous Sulfate stain on a ferrocement thin-slab
radiant floor at my house.
http://www.cathy-moore.com/house/stain.html
I bought a few pounds (minimum quantity as I recall) online for < $20
including shipping, from a ceramics supply place--and I still have most
of it after completing our 225sf floor.
I only did one coat, hand ragged from a bucket. I think I avoided all
the issues of accidental bucket or boot prints by staying off the
finished part as I went along. I also didn't wet the floor first. There
is a mottling where it's stronger or weaker but that's what I was
shooting for and it doesn't look like a mistake. 
On my concrete it came out more brown than red, kind of a light
paper-bag color. Wonder if the cement makes a difference? I know when we
pour concrete around here, we sometimes get dark gray, sometimes light
gray, others a tawny tan color. I assumed this was due to different
cement from different sources. YMMV on the color it appears.
The stain has held up great. It's been down for four years now and no
noticeable fading. The room has southern glazing and gets lots of sun on
one end, so I'm confident there's no light-based fading in that finish.
It's our entryway and is very well used, often gets wet, muddy, sandy,
whatever is being tracked in by adults, kids & pets, with no issues
whatsoever.  
I covered it with home cheapo clear acrylic something. Mistake because
it was stinky, but the smell is gone now, and it too seems to be holding
up. I would plan on some clear coat of some kind, makes the floor less
porous and easier to clean, and should help lock in the heavy metals
from the flyash.

Doug
Doug Horgan, CGR, CGP

BOWA Builders, Inc.
  Celebrating 20 years of building relationships and award-winning
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