On 3/10/2011 12:12 PM, wrote:
On Thu, 10 Mar 2011 08:56:27 -0800 (PST),
wrote:

The paint on my stucco on concrete block house is chalky and peeling
and even cracking in a couple of places. Everyone here, in south
Florida, seems to pressure wash stucco before painting, but I am
wondering whether scraping then scrubbing with bleach and detergent
would be just as effective.

Here's a link, hopefully, that shows the cracking paint:
http://i51.tinypic.com/16hte2f.jpg

The stucco has what is referred to as a smooth finish, though I've
also heard it called a sand finish. But it's basically pretty smooth,
especially with several layers of old paint on it.

If a pressure wash is the way to go, what power of washer would be
necessary to clean it up?

If scrubbing would work, what kind of mixture would be best?

Thanks.

I have a 2700 PSI 3GPM washer and I use the 40 degree nozzle so it is
a wide fan spray that knocks down the power quite a bit but goes fast.
Be careful with too much power. It will eat that stucco right off the
wall.

Pressure washing is the only way to go...you want to remove not only
dirt, but loose paint. You want also to pay attention to
weather...allow at least two days of dry weather after p.w. and before
painting. You should prime any areas that clean down to bare stucco.

Our condo was painted by a contractor and had had badly peeling paint
with a lot of mildew under the paint...probably not p.w. before the
previous paint job. The contractor sprayed the walls with bleach
solution before pressure washing, which seemed odd to me but worked out
to a very satisfactory job. We had loads of loose paint blasted off by
pressure washing and we devised a pretty neat system for capturing all
the paint debris for disposal. I had used bleach previously (1:10 with
water) to clean bad mildew from behind some plants, with no damage to
plants or lawn - just rinsed it well, no major deal. Prior to the
painting, my husband and I repaired quite a few damaged spots on the
concrete block/stucco...corners knocked off by mowers, block broken away
around dryer vents, etc. We used latex stucco patch (sanded), using two
coats if the defects were larger...our stucco was more textured and I
made the patches match by hitting them with a bristle scrub brush. If
you need to patch, it's pretty easy to use and scrape away until you are
satisfied. That was 2001, and it has held up very well. Our bldg. was
about 40 y/o, and quite a few fine cracks in the stucco, and contractor
used brushable caulk to cover those prior to painting...much easier that
smooshing with your fingers if there are a lot of cracks.

You may also want plastic tarps to cover landscaping with, but have to
be sure to remove tarps right away so plants don't get burned.