loose coping, pool builder advice please

[tltmom]

Unfortunately, another new problem with my pool: ig gunite, built in fall 2010. Recently, I noticed the joint under the coping above the waterline tile cracked open about 1/8 to 1/4" around the perimeter of the pool between the deep end skimmer and the diving board. Coping sounds hollow when tapped. My pool builder plans to fill in cracks this fall, then remove the affected coping next spring and fix it back down properly. He feels that groundwater has been getting under the decking, and that a corrugated pipe drain covered by gravel along the pool deck edge would prevent water from continuing to cause the problem. Landscapers, who claimed to have a lot of experience completing projects around pools, did not put a drain there. Instead, what I have is a grass yard that slopes down slightly from my house deck towards one side of my pool deck. The rest of the sides of the pool deck probably drain adequately and seem unaffected. I remember questioning the designer repeatedly about whether the mild slope towards the pool would cause a problem with groundwater flowing towards the pool, but he was sure it would not. There definitely has not been any mud washed into the pool this summer when it rained, so I don't think the grading is too bad, but probably not good enough.

My question is this: will a drain be enough to solve this problem with the water getting under the deck or do I need to pave the whole grassy area and put in a drain. I'm not sure that a single 4" drain along the edge of the pool will be enough. I'm sure this will be hard to answer without a picture. If it would help, I can try to take one in the morning. As much as I hate to do any more construction, I don't want to do less than the full job to get the problem solved.

Thanks in advance for your advice.

 

[JamesW]

Pictures would help. Is the expansion joint filled properly with caulk?

 

[tltmom]

Yes the expansion joint was filled right away last fall and held up perfectly over the winter, aside from about 5 or so tiny spots that sunk in a little ways. These spots were not near the affected area anyway. These little spots were filled in at opening this spring. The pool builder opened for me and went around and inspected the expansion joint for me. They seem to be very aware of how important it is to keep that joint sealed and plan on watching it for me and probably replacing the mastic in 5 years.
I will post pictures when it's light enough.

 

[PoolGuyNJ]

The French drain system should be fine as long as they send the water somewhere down hill and away from paths, driveways and the foundation of the house.

I just did one that required I move the water over 50 feet away from the capture zone.

Scott

 

[tltmom]

As always, thank you for the super fast advice.
Here are some pictures:
problem area is to the left of the steppingstones, btween the deep end skimmer & diving board
[attachment=2:2yw4hdip]pool 6.JPG[/attachment:2yw4hdip][attachment=1:2yw4hdip]pool 7.JPG[/attachment:2yw4hdip][attachment=0:2yw4hdip]pool 8.JPG[/attachment:2yw4hdip][attachment=0]

 

[tltmom]

one more pic, showing the crack in the mortar between the tile and the coping.[attachment=0:12ycjhxp]photo pool 3 copy.jpg[/attachment:12ycjhxp]
My pool builder had the same opinion that Pool Guy NJ did, that a drain along the edge of the deck between it and the grass will help prevent this from happening again.
We will be getting that done asap before it freezes here.
Again, thank you for your advice.

 

[XsAllOverIt]

To me that looks like what I had. I had a much bigger case of it and it was clearly heaving due to the winter we had last year. Heaving is caused from residual water underneath the decking. They repaired it last year and I've got my fingers crossed for this winter.

 

[tltmom]

By repairing it, do you mean pulling up & resetting coping? Did you need to do any drainage or other remediation to prevent the coping from loosening again?
BTW if I had not been doing a lot of reading on TFP, I would not have realized that the cracks were actually a fairly big issue. Thank you to all of you for this great forum!

 

[XsAllOverIt]

They didn't put the caulk joint until real late in the season - late November last year and it was a crappy job with many cracks. I believe that may have caused the problem and that's why I'm keeping my fingers crossed for this winter. They came back and took all the caulk out from the previous install (incidently they came back twice the first time and it still didn't look sufficient last year) and never put the caulk back in. I did it myself in early July so the ground underneath certainly had plenty of time to dry. We have an entire french drain around the entire pool and had MUCH rain this year, so I'm hoping all will go well this winter.

 

[tltmom]

ours was caulked correctly but it looks like not having any drain along the grass edge with the decking is the culprit.
so glad I trusted the "professionals" to think of all these details for me.
yet again, I wish I had found TFP before I had the pool designed/built. Fortunately, I think we had an excellent builder. It's the landscapers that are the PITAs.