This is a multi-part question: 1. Is there any caulk rated for outdoor use that can be used below 40 F? What about use in damp conditions? I wager no caulk likes cold weather. 2. Even if caulk sets under the best conditions, won;t cold temps cause it to become brittle and crack? 3. If caulk is not silicone-based, what else would it be? - Jinx
Caulk can be latex based. Silicone is better (more flex, longer lasting, less brittle), but harder to work with and clean up.
For working outside, have the caulk at room temp and you should be able to work with it. As for wet conditions, you just aren’t going to get caulk to set up on a wet surface, and if you appear to, it won’t last.
Caulk rated for outside will remain plyable, despite being cold. I wouldn’t exactly recommend you go picking at the caulk around the window outside when it’s 10 degrees outside, but it will adhere, flex and provide that barrier that is required.
Caulk can be had for ‘moldings and doors’, ‘tile and bath’, ‘gutters, windows and flashing’ and a lot of other purposes. Outside, go for silicone and be prepared for clean up with mineral spirits.
Inside, I use latex on woodwork, as it cleans easy, spreads easy and doesn’t ‘shine’ through paint jobs.
I’ve got some stuff in the basement that was referred to as “quad” caulk. Don’t remember what’s in it, but it is a bitch to work with, but works in the cold pretty well. I’ll try and remember to check it out when I get home.
A note on silicone caulk - it generally will not adhere to block or concrete very well. There are many varieties of caulking and you should talk to someone at your local building supply about the best application.
Look for elastomeric caulks.
What Philster says…
Following up my original post, OP Jinx, see this article:
or
http://www.tremcosealants.com/fileshare/instructions/COLDWEATHERproduct.pdf