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I used Dap siliconized latex caulk. They also have similar caulk with 50 years claim. Urethane caulk, at least the one I used, was already starting to cure in the tube and very difficult to apply with the gun. I read somewhere that the urethane caulk has to be right out of factory to be useable. If possible don’t rely on caulk to shed water, be mindful of the gap size and caulk after priming.
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I am looking for the best type of exterior caulk to use around my windows and doors. The silicone-based caulk that was used is all cracked and separated.
I live on a mountain ridge in Huntsville, in North Alabama. We have high heat and humidity in the summer, and almost no humidity in the winter when the temps get down to 10 to 20 beg F. My house is two years old, brick veneer. The windows and doors are wood. They are currently painted with oil-based paint.
*Check out the article on the Journal of Light Construction on caulks.www.jlconline.com/jlc/archive/exteriors/caulk/index.html
*Vulkem 116 is one of the best. Urethane based.
*I used Dap siliconized latex caulk. They also have similar caulk with 50 years claim. Urethane caulk, at least the one I used, was already starting to cure in the tube and very difficult to apply with the gun. I read somewhere that the urethane caulk has to be right out of factory to be useable. If possible don't rely on caulk to shed water, be mindful of the gap size and caulk after priming.
*I asked this exact same question about 6 months back. Try this link. I found it using the Breaktime b search feature and "best caulk" for the search string.I have had the same problem as Kwan describes with polyurethane being already partially hardened in the tube.Most people around here use silicone, although it is not my first choice. I have also used elasomeric caulk which seams about bullet proof, but still flexile, and is very clear, however it is hard to work with, and you often must do the job twice as it shrinks so much on the initial cure.Also check the BIA technical Library< as I know they make specific recommendations.
*Joe, I like to use latex-silicone based when doing cosmetic caulking but for durability and weather tightness I use polyurethane based caulking. I've found that caulks that hard to apply and tool are the toughest lasting one's. I stay away from any 100% silicone caulks, my experience with them is not god> Skip
*A vote for PL polyurethane, when looks are not paramount. Paintable, tough, and messy. (Vulkem smells horrible!) Otherwise, almost everywhere, Polyseamseal latex, great stuff.It has been suggested in print that the "siliconized latex" is a gimmick; I have no idea whether they're worth the extra money.Still haven't broken open the $$$ Lexel.
*I like the Tremonic polyurethane caulks, but they are, as noted, shelf life sensitive. My supplier buys small quantities, very often, so that's not a problem. Trexel rules in low temperature settings, I believe, though it works hard and it's expensive.
*For caulk that needs to move & a fungicide is not a requirement Dap 230. It also paints well. Tubs 7 kitchens polyseamseal polyurethane. I also like Sike polyurethane's but they can be expensive & hard to find in my area.
*Geez, now you have to be a chemist to understand caulk!Can anyone tell me what "caulk" originally was? Anything handy to stuff holes? ("Daub and wattle?")
*Original could go way back. Early caulks were probably plant fibers (oakum, hemp) tamped in place and tarred in boats. Mud and clays with moss in houses (chinking). I suspect caulk was more of a nautical term originally.Of course I could be wrong.Andrew, if you think Vulkem smells, never use their roof coatings. They make roof coatings that off gas for months and are not approved for residential applications.joe d