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Need advice on sealing windows

Hey --

My windows which are 1 and 2 years old now (brand: Milgard, professionally installed), are starting to break away from the caulking both on the outside and the inside. I've had the company return to re-caulk one of the 2-year old windows, only to now have it crack AGAIN. Initially they only were breaking from their caulking on the outside (I have a stucco exterior), but now the vinyl strips covering the inside perimeter of the window are starting to break from their caulking. Note that the caulking is splitting in the middle of the bead (as opposed to separating from the surface it was applied to).

My question is: what is the best way to keep the windows sealed?

From what I can tell the caulk they are using is the right kind (DAP Alex Plus 35-year). The company who installed it said that it is meant to be painted, and suggested that since it has not been painted, this might cause it to be more susceptible to cracking. I've read that silicone caulking is more flexible, but also it's not paintable (which is a problem, since I will want to paint it at some point).

I have a hard time believing that the solution is to re-caulk my windows every year, there has to be a better solution.

Hope someone here can help.

Re: Need advice on sealing windows

ok definitely not a good thing having the caulking breaking..

but heres the first thing, alex brand caulking is garbage, use a window caulking made by MULCO. either flextra or flex 9000 or OSI QUAD. they are both thermoplastic caulkings. they can flex up to 400x their own volume and dont pull away from what they are being caulked too

ive installed countless windows both for new construction and replacements on renovations. ive seen the caulking fail more times with silicone than thermoplastic caulking

Re: Need advice on sealing windows

thanks for the tip! I'll see if I can find some of that thermoplastic stuff. I assume I can paint it?

Re: Need advice on sealing windows

jk I havent used the thermoplastics sealants much,but I thought they were more of an exterior product. Isnt it like Butyl caulk.

Re: Need advice on sealing windows

yah, and its paintable, you can get it in a variety of colors too off the shelf, for a dollar or two more some makers have color match to all the colors of siding currently in production

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