wrote in message
oups.com...

jeffc wrote:
wrote in message
ps.com...
I think etching becomes less of a requirement for older concrete. The
purpose of etching is to give the concrete a rough surface so the paint
will stick. If the floor has become rough over the years from wear,
for example, then I wouldn't etch it.

Actually, sometimes concrete becomes "polished" and smooth over time, and
is
in the most need of etching. Fresh concrete rarely needs it.


That's just totally false. Read any paint can or guidelines for
painting concrete and see what they say. Etching is always required
for new concrete.

No it's not. Really new concrete is going to be very alkaline which is a
problem. Obviously concrete can be poured and finished in a variety of
ways, some more smoothly, some less smoothly. Now this guy is talking about
a crawlspace which obviously doesn't get any traffic. But concrete that
gets traffic definitely gets smoothed over time. Not only that, but the
tiny nooks and crannies can get filled in with dirt and grime. In addition
to etching you should clean and power wash (clean first, etch second, power
wash third to get the concrete particles removed.) You think you need to
etch concrete that's "rough" like a sidewalk? No.