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John Ross

wrote:
John Ross wrote:
Just installed a dryer vent pipe hood through outside wall, which is
stucco.

Caulk was put around the aluminum hood piece that was on the stucco. I
didn't do this myself, so unfortunately I can't give exact details of
caulk except that it was supposed to go on white and then turn clear
after curing and I assume silicone.

The dryer was used less than an hour after this. I noticed that the
caulk on top (which had a good gap between it and stucco) had sorta
"swellled" up so it is now protruding upwards quite a bit (although
still meeting wall and plate). In addition, it stayed white and is
rubbery to the touch, not hard. The sides mostly turned clear, but have
a sticky feel to them. I assume the intense heating of the aluminum
screwed up the caulk so it didn't cure correctly.

What can be done? The problem is that if you try and take off this
caulk it will damage the stucco (unless there is a chemical way to do
it). If the excess on top (which is the part that is cosmetically
unappealing--kinda like someone took a tube of toothpaste and squeezed
it out--is cut down a bit (before getting to stucco), can new caulk be
put on top of the remaining bad caulk? Will caulk stick to caulk
anyway?

Any ideas? I am lost because I have a feeling that the stucco is going
to be damaged and the cure worse than the problem.
--

John Ross

I have used an acrylic caulk which is advertised to "go on white,
cure clear". Cure actually means the water carrier evaporates so that
the latex particles can coalesce.

Mine took quite a while to go from white to clear. The water has to
diffuse from the inside of the bead before the bead becomes clear. At
that, mine didn't end up water-white clear but it was clear enough
for my purposes.

Most acrylic sealants will stick to cured acrylic. I would wait a
while to see what happens before attempting a repair job though. I
had some thick beads near the roof which took months to reach their
final degree of clear.

Every clear silicone sealant I have ever used went on clear and cured
clear. Stuff that went bad in the tube remained "clear".

-Jason

On your thick ones that took months to "reach their final degree of
clear", what consistency were they during that time? Were they still
soft? But, again, the difference here is that it seemed to swell up.
Also, the parts that did go mostly clear are sticky--did you notice
that?
--
John