Need Advice on Caulking Mishap

[John Ross]

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.

[trader4]

How long has the caulk now been on there? Every vent of this type that I have seen, it's hard to imagine the perimeter of the device with the louvers getting hot enough to interfere with caulk setting up. Even if you applied it directly to the pipe, I would be surprised if a dryer vent pipe could get that hot. I would think it more likely the caulk just hasn't completely cured yet.

I'd wait a few days and see what happens. If what's there is firm and cured and you want to go over it with another bead, you can. I also would not think it should damage the stucco if you want to remove it, but I'd only do that as a last resort.

[m Ransley]

Silicone caulk that does not cure properly is old and should not have been used

[jazon48]

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

[Norminn]

Let it cure completely, then trim the excess off with a razor blade or utility knive. If it isn't adhering to the stucco/vent, it should pull away easily. I certainly wouldn't think of splashing chemicals on it unless it is running down the wall. Is the stucco painted? Color? I can't imagine the color of the cured caulk being important if it is trimmed back and a relatively even line.

[Norminn]

clipped

When our kitchen was remodeled, the contractor used a white-to-clear silicone caulk. I have no doubt it is silicone, but have never used the sil. that changes color myself.

[steve]

john,the aluminum dryer vents dont have vents, the plastic one do, no the heat couldn't heat the caulk, if the caulk is very thick it will take a long time to completely cure, if it stays soft and rubbery, that is good, the junk caulk gets hard and eventually dries & cracks, if it is sealed , the caulk can be painted. and yes you can caulk over old caulk but probley not over silicone. sr ,

[lwasserm]

Can you plant a bush in front of the vent?

[John Ross]

It is not the louver type. It is all metal hood type with metal flapper inside. It is only 4 feet away from dryer and gets VERY hot. It was done on Tuesday.

One issue that no one is picking up on is the "swelling" up. That certainly is not normal is it?

-- John

[John Ross]

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

[John Ross]

What did you mean when you said the heat couldn't heat the caulk? Do you mean high heat doesn't affect caulk or are just assuming it didn't get heated? First, let me assure you, it got VERY hot. Also, it swelled up, so something definitely strange happened.

Also, did you mean it was good to stay soft and rubbery forever or just until it cures?

-- John