best choice for window sealant

[bkbroiler00]

wondering what everyone's thoughts are on the best product for sealing up windows. i used silicone when i installed my first side window, and i used butyl tape when I did the roof vent. i'm cutting in some vintage parallelogram windows, and am wondering which product i should use? i'm leaning towards silicone since i don't know if the butyl tape will squish down enough between the body panel and the window frame. is there another product i should consider? i've seen body seamer, but not sure if that would be the best for this application. what are your thoughts? thanks for the input.

 

[Bikersmurf]

Don't know what is best, but I'd use SikaFlex over Silicone.

 

[QuadsBC]

I can't recall the name of the actual product (window weld?) it's the same glue that the glass companies use for windshields. It remains flexible to allow for hot/cold cycles. I've used it on a few projects with zero water intrusion.

 

[rex_1_mn]

I've used butyl for a lot of stuff. In a marine environment it's all I will use. May not be the best for big gaps. One trick with butyl is to give it time to squeeze and squish out. Tighten a little bit over the course of a few days.

 

[Bbasso]

I'd also recommended butyl tape, maybe a smaller size if you are worried or just trim 0ff any excess...

 

[luthj]

Window weld by 3m is a structural window adhesive (polyurethane type). It works great if applied correctly. It is designed for direct glazed windows (such as most windshields). It is tough to clean up and cures quickly. For a window with a mechanical attachment method butyl tape works. If the gap is small enough, I like adhesive closed cell foam tape. It is mess free, and easy to apply. You would use a single continuous piece with the ends meeting on the bottom. This worked great for my motion windows install which use a trim ring to retain the window.\

Do not use silicone. Some types will release acid during the cure. Once silicone has cured nothing will stick to it. Not even more silicone. So if you need to remove the window, you will have to mechanically remove all the old silicone before sealing the window again.