New to forums, but advice and help for “possible” spa leak

[jakemiller69]

Hi everyone from Raleigh NC,

I have some concerns with my pool build. Started at 1” water loss per day and about 1/2” now after leak company plugged some holes. Basic stuff they said and treated.

Question: is it a generally accepted practice to have any pool water ever touch non-plastered concrete in any way in that structure?


As you can see from the picture, the live stone around the raised hot tub area does not have the plaster like in our pool. They also did not use any water barrier of any kind or sealer. The builders did the live stone and then had the plaster company come in after that was done. I have some hunches and would love feedback.

 

[ajw22]

Welcome to TFP Jake.

The picture you posted does not show the pool water against the Spa wall. Can you post some close up pics of the area in question?

How did they grout between the stones? What type of grout was used?

You have any pics of the area during construction?

 

[jakemiller69]

Thanks for checking it out. I have a lot of pictures, I will attach some of the build process and current (to see how water sits against the live stone).
The live stone is my concern with the water sitting against it all day and night in that channel for the spillover.

 

[Jimrahbe]

Jake,

In my tiny mind, this is one of those things that looks so cool, but is not very functional... How are you going to clean between the deck and the spa? I am not a fan of anything touching the water except tile... I also do not think, that the stone will work well over time as it becomes scaled or calcified..

That said, I do not see any construction errors, but rather a design issue..

Thanks for the pics.. Let's see what our other members have to say..

Jim R.

 

[ajw22]

The buildup from the gunite on the spa walls should have including a waterproofing membrane like

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Your pics do not show how they grouted or sealed in between the stones. Gunite is not waterproof. What is under the footing of the stone?

@bdavis466 thoughts?

 

[jakemiller69]

The buildup from the gunite on the spa walls should have including a waterproofing membrane like

HYDRO BAN - Waterproofing & Crack Isolation | LATICRETE

HYDRO BAN is the perfect combination of load-bearing waterproofing & crack isolation membrane you could want! Get yours today!

laticrete.com

Your pics do not show how they grouted or sealed in between the stones. Gunite is not waterproof. What is under the footing of the stone?

@bdavis466 thoughts?

As a footnote, I am not very construction oriented and just have the internet to help my ignorance. But, my PB and hardscaper said they did not put that sealer and it’s not “standard.” I asked another pool company in my area to look and they affirmed that it isn’t necessary to do. But I am not sure they understand...

I also do agree it’s a design issue, besides cleaning hassle. We believe that this is a cause to our water loss without that seal.Is it possible that stone not having the seal under it cause the large 1/2”+ a day water loss we are seeing?

 

[Jimrahbe]

Jake,

What is actually leaking? Does the water in the pool go down or just the water in the spa?

Is the problem just when the pumps are off the spa level drops a little?

Or what?? Tell us why you think you have a leak?

Thanks,

Jim R.

 

[JoyfulNoise]

That submerged stone with mortar is NOT waterproof against the gunite shell. The outer wall of the spa should have been sealed from the base to at least 6" to 12" above the water line, kind of like how you have to use cement-board in a tiled shower from the floor and up the wall. Gunite on it's own is NOT hydraulically sealed. However, is that enough on it's own to cause the leak you are seeing....not so sure of that unless the gunite shell is somehow cracked.

Can you do a bucket test to confirm the water loss? 1/4" to 1/2" per day is not unreasonable but that's during the hot months....this time of year it should be less.

 

[jakemiller69]

Jake,

What is actually leaking? Does the water in the pool go down or just the water in the spa?

Is the problem just when the pumps are off the spa level drops a little?

Or what?? Tell us why you think you have a leak?

Thanks,

Jim R.

The pool is roughly 33,000 gallons and I am losing 1/2" - 3/4" almost daily since June. The leak company found a few little issues they plugged up, but the leak continues.

My theory: No sealant was placed behind the :"live" stones on the outside of the hot tub. Like a home, you want to seal this with a foam or some type of insulation to prevent water from expanding over concrete. In my case, we have water that is sitting on exposed concrete that only stone is covering it. Thus, causing water loss into the ground somehow.

I have to add 2 (40) lb bags of salt roughly every 2 weeks as I am putting in fresh water to make-up for the loss, so this would remove a lot of the evaporation theory my PB tries to convince me of. But, we have tried turning off the spillover (runs 2 hour per day to cycle) to make sure it was not in the hot tub and no water loss there. So, our focus is now structural, especially since a detection company has dived 4 times now and we still have the loss. We are at our ends wit trying to solve this one.

 

[jakemiller69]

That submerged stone with mortar is NOT waterproof against the gunite shell. The outer wall of the spa should have been sealed from the base to at least 6" to 12" above the water line, kind of like how you have to use cement-board in a tiled shower from the floor and up the wall. Gunite on it's own is NOT hydraulically sealed. However, is that enough on it's own to cause the leak you are seeing....not so sure of that unless the gunite shell is somehow cracked.

Can you do a bucket test to confirm the water loss? 1/4" to 1/2" per day is not unreasonable but that's during the hot months....this time of year it should be less.

Our thoughts exactly and that is our concern. We have done bucket test after bucket test. A few leaks were found around some pool jets and in skimmer basket area, but the detection company "repaired" this. I am in NC and the pool is not covered and open during the winter months and I am still losing 1/2"+ and that is on a bucket test result.

 

[JoyfulNoise]

I just looked at the first picture....did not realize you were doing a negative edge spa. That entire spa gunite wall, inside and out, should have been waterproofed.

If the spa is your leak source, the only fix will be to drain the pool, demo the spa surfaces and redo it. Salt water flow through gunite is a bad idea. The high chloride content of the water will not only weaken the concrete over time, but it will rot out the rebar. Is it an urgent failure, no. But you're not going to get the full life out of it. Unfortunately, the pool is built and the PB is highly unlikely to remedy the situation without litigation and an unbiased opinion from an independent civil engineering firm. I agree with @Jimrahbe 's opinion - the spa design sure looks nice on paper, but the implementation and long-term upkeep are going to be devils...

 

[jakemiller69]

I just looked at the first picture....did not realize you were doing a negative edge spa. That entire spa gunite wall, inside and out, should have been waterproofed.

If the spa is your leak source, the only fix will be to drain the pool, demo the spa surfaces and redo it. Salt water flow through gunite is a bad idea. The high chloride content of the water will not only weaken the concrete over time, but it will rot out the rebar. Is it an urgent failure, no. But you're not going to get the full life out of it. Unfortunately, the pool is built and the PB is highly unlikely to remedy the situation without litigation and an unbiased opinion from an independent civil engineering firm. I agree with @Jimrahbe 's opinion - the spa design sure looks nice on paper, but the implementation and long-term upkeep are going to be devils...

Why is the seal necessary around the inside and out? From a laypersons perspective.
We are now having the plaster company come back and fix a “rust” looking issue that appeared inside the hot tub. A spot has formed and they are going to have to now cut and replaster that rust area. I’m attaching a picture of the spot.

Needless to say, we just want this to find resolve and am willing to pay a structural engineer to evaluate.

 

[ajw22]

That rust area is likely rebar. My guess is with water leaking through the gunite the rebar is beginning to rust and the rust is coming up through the plaster. Whatever the plaster company does is not going to permanently fix the problem until you possibly cut out the rusting rebar and stop the rusting.

 

[JoyfulNoise]

Why is the seal necessary around the inside and out? From a laypersons perspective.

It is standard construction practice to use a waterproofing sealer at the bond beam around the pool. So the water line tile and coping should be attached to the pool's bond beam with a waterproof interface between those elements and the gunite. Similarly, the tile inside the spa as well as the coping on top of the spa AND the entire outer wall with the stacked stone facade should have had a waterproof sealer applied. The pool and spa plaster is considered waterproof and so no sealer is needed. If the inside of the spa had been all tile (some people choose to tile rather than apply plaster), then a waterproofing layer would be needed.

It sounds to me from your explanation that your PB was not doing this. Construction practices for pools vary from place to place and so it's entirely possible that it is "just not done that way here" where you are. However, out here in the "wild west" standard construction practice is to use a waterproof sealer on any water bearing surface that is not coated with plaster.

 

[jakemiller69]

It is standard construction practice to use a waterproofing sealer at the bond beam around the pool. So the water line tile and coping should be attached to the pool's bond beam with a waterproof interface between those elements and the gunite. Similarly, the tile inside the spa as well as the coping on top of the spa AND the entire outer wall with the stacked stone facade should have had a waterproof sealer applied. The pool and spa plaster is considered waterproof and so no sealer is needed. If the inside of the spa had been all tile (some people choose to tile rather than apply plaster), then a waterproofing layer would be needed.

It sounds to me from your explanation that your PB was not doing this. Construction practices for pools vary from place to place and so it's entirely possible that it is "just not done that way here" where you are. However, out here in the "wild west" standard construction practice is to use a waterproof sealer on any water bearing surface that is not coated with plaster.

I agree and thank you for your feedback, very much.
Do you have any rec’s on a title or type of person I go to for the independent third party validation of this issue? This is probably going to cost a significant sum and want to make sure I have everything needed.
My PB is on brink of bankruptcy (we hear) and most likely won’t make this right.

 

[ajw22]

Do you have any rec’s on a title or type of person I go to for the independent third party validation of this issue? This is probably going to cost a significant sum and want to make sure I have everything needed.
My PB is on brink of bankruptcy (we hear) and most likely won’t make this right.

Talk to Pool Engineering, Inc., Structural Design of Swimming Pools and Residential Improvement Structures and see how they can help you.

You need someone experienced in pool construction. The title does not matter, the knowledge and experience matters. You also need to find a local construction company who you trust who will renovate your spa area.

If all it will take to fix the problem is stripping the stone off the spa, apply a waterproof membrane, and tile the walls, then it is not that big of a job. However I would want to find some way to confirm the water is leaking through the wall the way we assume. All that water needs to be going someplace. I would want to dig around and under the spa area and see if wet spots can be found. I assume your water ahs CYA in it. You can test any water found around the pool for CYA to determine if it came from the pool.

 

[jakemiller69]

Talk to Pool Engineering, Inc., Structural Design of Swimming Pools and Residential Improvement Structures and see how they can help you.

You need someone experienced in pool construction. The title does not matter, the knowledge and experience matters. You also need to find a local construction company who you trust who will renovate your spa area.

If all it will take to fix the problem is stripping the stone off the spa, apply a waterproof membrane, and tile the walls, then it is not that big of a job. However I would want to find some way to confirm the water is leaking through the wall the way we assume. All that water needs to be going someplace. I would want to dig around and under the spa area and see if wet spots can be found. I assume your water ahs CYA in it. You can test any water found around the pool for CYA to determine if it came from the pool.

Thanks for the contact. I just sent them a note now. Recent bucket test was almost 1" loss differential from bucket to pool. My concern is where all the water can be going after it seeps out. But, starting with a structural engineer is the first steps I believe.

 

[jakemiller69]

Hi Everyone, Update here:

1) Had a structural engineer evaluate standards and the build quality of pool; everything was level and no improper tiling, etc
2) Another pool builder in the area came to look at the pool and was not "too concerned" of the hot tub live stone not being coated with any waterproofer
3) The engineer did see a exposed jet flow valve in the hot tub, so definitely something to be repaired and losing some water to

So after all this, I am back to square one in terms of why am I losing 1" of water per day. I have done all my diligence with hiring divers, engineers and other pool companies. The bottomline from engineering group is that it is "probably a combination of a few leaks causing that water loss."

Any suggestions for next steps would be appreciated and what to try next!

 

[ajw22]

Everyone is saying that they don‘t see any "smoking gun" pointing at where the water loss is coming from.

Your choices are:
- Live with the 1" a day water loss for a while. The water has to be going someplace. Eventually it may undermine an area and you will have something cave in or see an area of consistent wetness that you can track back to the pool
- Spend money ripping stuff out and changing things. I would remove the live stone and waterproof the spa walls and put on tile.
- Keep on bringing people in to look at the problem. Losing 1" of water a day in the winter is not right.

 

[JoyfulNoise]

Gunite is like a sponge, when it is exposed to water, it will soak it up. It not a hydraulically sealed material like plaster is. So the entire stone face of the spa outer walls, with no waterproofing material applied, allows any water in contact with it to seep in. As you cycle the spillover of the spa, the water will soak into the gunite and then evaporate away or get pulled into the ground depending on water saturation. It’s also a large, rough surface with a lot of water flowing over the stones and in & around the crevices. That will enhance evaporation during hot days. So it’s not all that surprising that you’re seeing water loss.

The comments made by those people you brought out to inspect their pool sound like hedges to me - they don’t want to throw the original PB under the bus and they don’t want to be responsible for fixing his mess. It’s like they’re just shrugging their shoulders and saying, “Meh! Looks ok to me?”. It’s pretty unusual to NOT waterproof a concrete wall that is exposed to water. Think about home construction with basements - you’d never build a basement without adding waterproofing layers to the outside wall that sits in contact with the ground! Same concept with a raised spa wall - if it’s going to see any water at all it either has to be plastered OR a waterproofing material has to be applied.

So I think you’re at the point where you either have to live with what you have OR spend a lot of money to deconstruct that spa and have the exterior properly engineered.