Caulking the joint between top of pool wall and bottom of coping stones

[steveg_nh]

I was reading another member's thread on caulking the joint between the coping and his concrete deck. The recommendation was something poly based. I need to see if I'm ok with what my patio builder wants to use to caught the joint where my pool walls (vinyl liner) meet the bottom of the coping stones.

This is narrow vertical joint, maybe only 1/8" wide. I've read a lot, and find references to elastomeric (what the builder is planning on using) and polyurethane, specifically, Vulkem 116. It was mentioned in another thread that poly is good, but the discussion was around the deck joints. There are lots of warnings on it about indoor use (not an issue of course) and potential cancer causing ingredients. I assume this is when wet, and not cured. But for this caulk line, which is only about 1/8" (except on the stairs where it's wider, and will have a backer bead behind the joint for support), is poly still the way to go? I don't want a mess when they do it. The builder says he uses this elastomeric and it's been fine.

Any advice/discussion is appreciated.

Thanks

 

[steveg_nh]

Just checking....any thoughts on this situation?

Thanks.

 

[duraleigh]

Elastomeric is an adjective....not a product. All flexible caulk has elastomeric properties.

I cannot quite picture where these joints occur. Can you post a pic?

Even without the pic, I am virtually certain I would suggest polyurethane caulk. It just seems to have better flex and better resistance to aging.

 

[steveg_nh]

So to your point about "elastomeric" I just assumed he was talking latex, but maybe I should ask...This pic shows it best (although you still can't really see it)...but right under the coping rounded edge, where it meets the wall and sits on ti, that's the gap to caulk, just above where the lines slips into it's channel.