# Caulk that's flexible and paintable and doesn't flash.



## detailssls (May 23, 2018)

Last year on my own house I used Dynaflex and SW950A and they both flashed shiny even after spot priming w/latex. Now, for this job I'm looking for any and all caulk suggestions for Hardie board butt joints and the rest that won't flash and remain flexible. I've read conflicting reports on caulking Hardie butt joints, but some of them on this job are previously caulked (failing), huge (1/4"), and there isn't any flashing as far as I can tell. Any help or recommendations much appreciated.


----------



## detailssls (May 23, 2018)

I should add that I'm using flat finish on the siding and Arborcoat on the shingles. The painting contractor whom I worked for always used Alex fast dry : ((


----------



## finishesbykevyn (Apr 14, 2010)

detailssls said:


> I should add that I'm using flat finish on the siding and Arborcoat on the shingles. The painting contractor whom I worked for always used Alex fast dry : ((


Lately I've been using the All Pro. Pro Stretch. Acrylic Urethane Elastomeric caulking. 
The only reason your caulking would flash after priming and painting is because of a difference in texture. IMO. That's normal.


----------



## MikeCalifornia (Aug 26, 2012)

1/4" is too much gap for any caulking to bridge. Flashing would be the least of my concern. If you need to fill a gap that large, use urethane. Your paint only flashes over better caulkings because it remains wetter for a longer period of time. Over Alex, cheap ass latex, it the same as flat paint over flat, flat over semigloss will take longer to dry.


----------



## lilpaintchic (Jul 9, 2014)

Quad max if you really HAVE to fill those gaps. Ime, they're best left alone...i use qmax because I can paint it in 24 hrs, not 10+days like the other quad....if it's flashing it's likely because it was painted before it was finished gassing off.....we used to deal with a TON of vulkum like that. Entire new neighborhoods striped because nobody followed the directions....smh. 

Sent from my SM-G930V using Tapatalk


----------



## cocomonkeynuts (Apr 14, 2017)

sashco big stretch


----------



## PNW Painter (Sep 5, 2013)

For Hardy I prefer something like Dymonic, Quad or SikaFlex. These products are more common on commercial projects.

These sealants barely shrink, can span a larger gaps and have a higher joint movement rating compared to more traditional painters caulks. 

The downside of these products, like Lil mentioned, is that you have to wait about 5-7 days before they’re paintable. You also have to clean with mineral spirits.






Sent from my iPhone using Tapatalk


----------



## DeanV (Apr 18, 2007)

Tower Tech 2 claims to not flash, I have not noticed flashing with it. AllPro does have that product rebranded as one of theirs as well.

But, I am not sure I like the idea of caulking the butt joints either.


----------



## lilpaintchic (Jul 9, 2014)

DeanV said:


> Tower Tech 2 claims to not flash, I have not noticed flashing with it. AllPro does have that product rebranded as one of theirs as well.
> 
> But, I am not sure I like the idea of caulking the butt joints either.


Exactly...they're designed to expand and contract....provided the siding guys installed it right it shouldn't need caulk at the butt joints.

Sent from my SM-G930V using Tapatalk


----------

