Sikaflex melts felt/bituthane?
FlyingContractor
| Posted in Construction Techniques on
Heard today some information from an older GC who I trust that some sealants, specifically Sikaflex actually disolves felt paper as well as vycor type products. I cant find any information regarding that from the manufacturer, so now I am really curious, have you guys heard this or is it like the much disagreed agrument about tyvek and cedar, etc?
If it is true, what are ‘correct’ window and door sealants over felt or vycor? I have generally used Phenoseal with good results, hope that’s ok!
Thanks!
Replies
Probably has a mineral spirits component.
There are definitely compatability issues with self adhered flashings and certain types of sealants. Graceconstruction.com has technical letters available to those who register. The letter specifies that you should not use sealants with a high solvent content. That's not much of an answer.
I use protecto-wrap brand self adhered flashing, and my supplier gave me a tech sheet detailing specifically what I cannot use, what brands are reccomended, and also what types of wall sheathing present what types of problems. I have seen some houses where there are black streaks running down the lap siding under the corners of the windows, due to dissolving sticky flashing. Our Milgard rep sites that as an example of poor compatiblity between sealants and flashing.
Basically, you need to do the research before you match up your materials. The factors I look at are:
type of wall sheathing (Foam board, OSB, Celotex etc)
Temp at time of installation
Material of window (Some vinyls don't like some sealants)
Brand of sticky flashing
Type of House wrap
ASTM/type/brand of caulking/sealant
These are all factors that I will bring to a potential clients attention to help show that maybe I cost more than a competitor, but I have the knowledge/experience to avoid the common pitfalls.
If theres any thing I missed or erred on, I hope someone will step in and educate me.
Thanks
That's the word. My stucco guy told me this some time ago.
Oh yeah, I forgot to add, that 35 year, siliconized, dap brand acrylic latex caulk works fine. It's a whole lot easier to use too, cleanup-wise.
I avoid the self adhesive products except when building the pan under the window.
They are no substitute for lapping all the products shingle style.
I do use tyvek tape on the tyvek and silicone on the flanges.