On 3/4/2011 10:48 AM, Bob wrote:
Hello,

A few fairly light to medium orange water stains have developed on our
white bathroom ceiling due to water dam. The typical problem.

A bit on in age now, and I would like to have to re-paint the ceiling
only once, if practical. It's a real job for me to do nowadays.

I know the smart way is to coat the stains with, I think I read to use
shellac (?), and then a white paint. This is supposed to prevent
additional bleed-thru.

Is there any product I can use that stands a good chance of doing it in
one coating/step ?

What about this KILZ I've heard about ? Would that do it in a single
step and prevent further bleeding thru of the stain
(assuming no more water leakages) ?

I think there are also similar products under different names, perhaps ?

Any thoughts would be most appreciated.

Thanks,
Bob

Kilz is a brand name with a number of different kinds of primers. I
think one of their earliest primers was shellac based, and they still
make that. The shellac based primer has nasty fumes, and a water based
(latex) stain-blocking primer would probably be a little easier to use.
I've used both, as well as other brands. You don't need a primer that
COVERS the stain, you simply need to seal it up and isolate it so that
it doesn't bleed through the final paint coat. Kilz, Bullseye and other
major brands make good primers. One can just prime the stained area and
feather out the edges, but that sometimes can give the final paint coat
a different gloss...best to coat the entire ceiling. Be sure the
surface is entirely dry - in a bath, the moisture from showers can lurk
for hours, so drying the ceiling with a towel prior to coating it is
probably a good idea. Here is a link to Kilz website:

http://www.masterchem.com/masterchem...8a 05d103RCRD