Polyurethane caulk recommendations

[JamieP]

There is about a 6' linear section of grout between my waterline tile and precast concrete coping that is cracked enough to let water in. There must have been some settling to cause this as the coping sounds hollow underneath along this section when I knock on it. I'm thinking the crack needs to be sealed.

I read on this site that polyurethane caulking is recommended, but when I went to Lowes I only found one thing actually labeled as polyurethane and it didn't get too great of reviews when I looked it up online when I got home. Since I'm not familiar with caulking, I'm wondering if anyone has a particular product and brand that they'd recommend in my situation? I want to do it right the first time. In case it matters, we also have a Home Depot close by so I can shop there too if that's the only place I can find something.

Thanks for your help!

 

[pooldv]

Sikaflex is the brand my PB uses.

 

[JamieP]

Thanks pooldv. That does seem like the go-to caulk for this application.

I've been doing some more research and found you recommended pool putty to another member not long ago in a similar situation. Do you think that is preferable for me? It certainly sounds easier. But maybe if I'm getting movement there, a flexible seal would be better?

 

[pooldv]

I didn't fully read/comprehend your question. Depends how big the crack is. If the crack is 1/16" or smaller hairline crack then the putty would be easier and work better. If it is bigger then the caulk will work better. It is fairly normal for some coping stones to have a hollow sound. Some of ours do too. Yes, you likely have some soil movement with summer heating up and drying and contracting the soil. We have a micro-irrigation system from Lowe's around the pool to help maintain even soil moisture and reduce movement.

 

[camueller]

MasterSeal NP1 Caulking Sealant, STONE, 10.1 oz.

This is the stuff my dad, a PB always recommends to me. I haven't found it locally though, but I've found equivalents at Ace Hardware, though kind of pricey. And it comes in other colors beside Stone. I just linked to the above because it was the first thing that came back in a google search.

 

[BigEinAZ]

Used to be Sonneborn NP-1. They sold or rebranded as Masterseal. If you see Sonneborn NP-1 in a builder supply house it is the same product.

 

[camueller]

Used to be Sonneborn NP-1. They sold or rebranded as Masterseal. If you see Sonneborn NP-1 in a builder supply house it is the same product.

Good to know, I'll look for that next time I need any.

 

[Rossterman]

I just used the lowes and homedepot sikaflex SL to redo the expansion joint on our pool. Here are my thoughts:

1. when they self leveling (SL) they mean it. It is thin enough that any minute ability to drain into the foundation will allow it to do so. I put new foam backer rod and it was tighter in some places than others but still compressed on both sides. Caulking ran right through it and drained down in a couple locations. Brought larger size for the other side of the pool. Ill probably install the rod and add a small amount of sealant then come back a second time to fill it fully after the first dries.

2. Color mixing in the tubes isnt complete. Caulking isnt fully color mixed in each tube so the first few squirts of calking come out white, stripes of sandstone color, then finally the color you pay for. This in my opinion is unacceptable! Others have had the same experience so not an isolated issue. Your only workaround is to squirt it into the trash until you confirm its color is OK.

3. I dusted mine with sand afterwards which leaves a nice finish and blends nicey with the travertine coping and sandstone concrete.

in conclusion, would I Do it again using this caulking material? Probably not but Im not sold on paying several $100 for the two part deckOSeal just yet either. Will see how well this lasts and go from there.

 

[camueller]

I just used the lowes and homedepot sikaflex SL to redo the expansion joint on our pool. Here are my thoughts:

1. when they self leveling (SL) they mean it. It is thin enough that any minute ability to drain into the foundation will allow it to do so. I put new foam backer rod and it was tighter in some places than others but still compressed on both sides. Caulking ran right through it and drained down in a couple locations. Brought larger size for the other side of the pool. Ill probably install the rod and add a small amount of sealant then come back a second time to fill it fully after the first dries.

2. Color mixing in the tubes isnt complete. Caulking isnt fully color mixed in each tube so the first few squirts of calking come out white, stripes of sandstone color, then finally the color you pay for. This in my opinion is unacceptable! Others have had the same experience so not an isolated issue. Your only workaround is to squirt it into the trash until you confirm its color is OK.

3. I dusted mine with sand afterwards which leaves a nice finish and blends nicey with the travertine coping and sandstone concrete.

in conclusion, would I Do it again using this caulking material? Probably not but Im not sold on paying several $100 for the two part deckOSeal just yet either. Will see how well this lasts and go from there.

As with many things, you can't buy the good stuff at the Box Stores. You have to find some place that sells the better made stuff. I refuse to buy caulk from Home Depot again, I don't care how much cheaper it is.