Recomended Caulking

[Sprint54]

I have an IG concrete pool. There is currently caulking between the ceramic tile (the tile at the water line) and the coping (I've seen it called decking and top cap). At any rate, the caulking needs to be replaced. This area is always wet when the pool is in use, but rarely is completed submerged. The gap is approximately 1/2" wide. I'm assuming the existing caulk should be replaced with an equivalent caulking. Anyone have any recommendations on what type, what works best? Thanks in advance for your responce and help.

Scott

[duraleigh]

Hi, Scott

Wow, that's a pretty big gap for caulk. Is it vertical or horizontal? I'm assuming it's vertical since it seems to touch the waterline tile.

Well, without seeing it (can you post a pic) I've always felt polyurethane caulk was the most durable for pool areas.

I am a little concerned that poly may "sag" a little while curing on that vertical plane. Worse, I can think of no way to prevent it. Silicone sags less but I dont think it's long-term characteristics are as good as poly.

Give us a little more info. Confirm the vertical plane. Post a pic if you can. Perhaps some of the pros will be along soon and will have experience filling that large gap....it's a little larger than I'm accustomed to and I'm not confident in my advice.

Dave S.

[KurtV]

That area is usually grouted instead of caulked; are you sure it's caulking?

[Sprint54]

Thanks Dave and Kurt, I'll get a picture posted today. The pool is currently covered and winterized, but this is a good reason to get the cover off early. Actually was planing on doing it this week anyway. I'm fairly certain that I could penetrate the caulking , or grout, with a finger nail last season, but I could be wrong. The joint being grouted just makes more sense. Look for a new posting and confirmation if it's caulking or grout today. Thanks again. Scott

[Sprint54]

Well that didn't take as long as I expected. Just removed some of the cover tension springs and pulled the pool cover back from a corner to get a peek for the camera. I believe it's caulking. The gap is about 1/4" at the minimum to 1/2" in some spots. It's not grout, like the tile grout, as I can stick a finger nail partially into it, it's chalky and has some flexibility to it. I've attached two pictures for reference. Let me know what you think. Thanks
Scott

[KurtV]

I think you're right that it's caulking. I don't know enough about that to make a recommendation.

[duraleigh]

Hi, Scott,

(nice pics...thanks) (nice coping, too...I like that look)

Pretty sure that's acrylic caulk (acrylic shrinks). Too bad they used such nice coping material and short changed on the caulk.

Anyway, I believe your course of action is to remove the old caulk and replace it with a high quality polyurethane caulk. Removing the old is probably going to be 75% of the work. I'd start on a small section and get your system perfected start to finish.

Once you get the section cleaned out...doesn't have to be perfect...be sure to use masking tape on both top and bottom of the new caulk line. I have had very good success with a caulk named Vulkem 911. Comes in many colors and not too much money...about 3.25/tube, I think.

Again, the poly is tough to work with (not water soluable) and takes days to dry out but you'll never have to replace it again.

Dave S.

[Sprint54]

Thanks Dave. Spent 5 minutes searching the Web for Vulkem 911 and get several hits but have not found a site that sells it. Any idea where I can get this stuff? Also, replacing the caulking is just one of many items on my spring startup list for the pool. The list includes, pool caulking (which this is about), acid washing pool, replace pump seals and replace pool decking caulk (the stuff you walk on). Since I'm doing all this, I'm just wondering about your comment, 'nice coping, to bad they used caulking'. If I am going to remove the caulking and drain the pool, is there another choice that would be better? Hate to go through all this and find out later that I could have had xx but I settled for yy. You know what I mean? The extra work I'm not worried about and if the xx is only a few more dollars but better for the long run and aesthetics, why not do xx. Anyway, your thoughts and help are appreciated. Thanks Scott

[duraleigh]

Hi, Scott,

I misled you a little on that post. I should've said "too bad they used acrylic caulk instead of polyurethane caulk" You must have a flexible seal at that point because the pool vertical wall and the coping move independently of each other...not much, but they move. If you try to grout it, it will crack before you know it and possibly fall out if your temps are extreme enough.

I suspect they used acrylic caulk on your expansion joints on the decking as well. Again my advice would be to switch to poly when you get the old cleaned out. The depth of the caulk should roughly equal the width of the gap you're filling. Masking tape on each side of the joint is mandatory.

I got that Vulkem stuff at a local (I don't think they're a chain) industrial supply house that specializes in masonry accessories. Drains, waterproofing, etc. It's called "General Materials" The Vulkem is made by a company called Tremco. I'm sure there are others just as good but this one works so well for me, I've never attempted anything else. I hope you are able to locate it but, if not, talk with some concrete pros in your area and ask them what they use to seal expansion joints.

Dave S.

[Sprint54]

Thanks Dave.. Going to Reno on Friday and have some concrete supply stores to call on. Appreciate your help.

Kind Regards,
Scott