Here are the pics...
BTW... the PB is being very reponsive to this problem and seems to be willing to do whatever it takes to get it right.

Could you please post some pictures of the spa being built?

Devildog,

IMO you do not have enough steel in the pool. I know every area is different but you still have clay soil which is highly expansive. Since you are digging into a slope that alone requires extra steel. When you get into expansive soils, most pool engineers will require additional steel. If you have had rain this spring all that water soaks into the ground runs under the ground and puts pressure up against the pool walls. If you do not have adequate steel in the walls the shell will crack. I'm surprised your shotcrete guy is taking responsibility. If your city or county does not require engineering plans the builder will put in what he deems is necessary. You see similiar things when decks lift when they are at the bottom of the hill and they are squeezed between the hill and a retaining wall without adequte drainge behind the wall, water build up behind the wall swells the soil and the deck lifts.
Or it could just be a bad prep on the tile job. But it looks like something is making that tile crack and move.

We do not have a pool but we have friends who do and have seen their pools under construction--as our neighbor's...
their pools were not nearly as large or on as sloped a lot as yours--and their spas were flat with the pool--not elevated--and they had more rebar in their pools...

I went back and read your pool thread--
you have quite a bit of fill because of the slope...and you had some problems with construction as well

could these cracks just be the beginning of more in that they come from movement in area around the pool?

PS--I also read where you said the project manager only came around to pick up the checks--
I know my comments are just rude--but aren't you worried that these cracks could be precursors to something more serious...

there are some PB on this forum--
hopefully they will look at your thread and give you some feedback--
what are they going to do if their remedy does not work and/or looks tacky and you are not satisfied?
What is you get cracks in another part of the spa in 3 months?

Devildog: The pool 'builder' that ncrealestateguy picked doesnt build anything. They just sell pools.Everything is sub-ed out to companies that will do exactly what it takes to get a check,nothing more. I agree that the problem is the light steel schedule and should have been prevented.

This is an obvious structural failure or else they would not admit fault or repair it. This pb has lots of corporate lawyers to keep lesser claims in limbo forever.

Engineering plans? If so the steel crew never saw them or knew how to read them. And I guarantee no engineer actually saw the pool (until maybe now). Are there any of you out there to comment?

well you can check his past posts and see who he used--he posted the name...
I looked at other pool builds last night trying to compare how the rebar looked in different pools--
some pools had about the same look of steel--but most of them were pretty flat pools w/o big raised spa or lots of backfilling from what I could tell on the photos...

one of the pools I saw shows smaller diameter vertical rebar within the square sections in certain areas (#55 photo)--and lots more rebar in like floor of the spa
I am posting link to that pool build so you can see the difference...just go to the next link to see other photos

sorry I did not think to lable the photo in my favorites so I could say what the gardenweb user's name was so you could check other photos...but it looks good to me--

that is how I want MY pool to be done...at least that much rebar
and the dirt behind it does not look like clay soil either IMO

Here is a link that might be useful: extra rebar in pool

It doesn't matter what the soil conditions are in this case, a failure was going to occur. It appears there was no engineered plan being used.
Were any inspections made by the building department or a permit required?
Generally speaking, an engineered plan would specify #3 @ 3" centers on the vertical both inside the pool and the spa, minimum. Continuous steel in the bond beam would also be a must.
Unfortunately, the fix described is a band-aid. A better fix would be to remove 3'(minimum) on either side of the spillway for width and 3' down from the top of the beam. Then drill and epozy rebar on the vertical and horizontal making sure to tie to existing rebar also. Good luck.

Mikethepoolguy I know what company you are talking about and I agree. The bond beam should be a minimum 3 bar continuous bond beam. The other parts of the pool would be dependant on depth, raised beam etc. Most of it would be #3 at 3" O.C. although on the deeper depths with the raised beam it could be 2 #4 at 4" O.C.., but if there was no engineering I guess it doesn't matter at this point. Even on the pool that loves2read shows it should have been a 3 bar beam and I usually run my 3 bar bond beam all the way up the raised bond beam. Although the pool was acceptable to the inspector ( I think that pool was built in socal)It was just a different engineer that I use and that was his schedule and was accepted by the city.

The only inspections required in NCREG's area are bonding, final electrical, and health dept.( which is to look at the fence and make sure they didnt put a diving board on a 5' deep pool).

Only once, in hundreds of pool inspections did an inspector require additional steel on my jobs.

This lack of enforcement provides for lots of oppertunities to cut corners. (until a pool is round)

It also allows the customer to get the best price. In previous threads I mentioned how customers often demand crap.

Its a shame though, Its a beautiful pool.

ncrealestateguy, I'm sorry to hear of your misfortune. It's a beautiful set-up you have there! I hope you can get it corrected.

In the pictures above that ncrealestateguy posted, the bond beam re-bar is there around most of the pool except for that area around both sides of the spa. It leads me to believe that for some reason, the steel guys weren't able to complete the job before the gunite stage.

Those pictures will definately help him support his claim because it clearly shows that the bond beam re-bar adjacent to the spa is missing while they were shooting the gunite. To me, the guys that did the gunite are not to blame, it's the steel guys, the PB, the inspector, and the engineer for not noticing it and correcting it before gunite.

The quality of the work on this job is terrible. The excavation, plumbing, shotcrete and tile work are all substandard. This is probably just the beginning of an epic journey of problems on your pool. Its a lot harder to fix these problems than it is to build it right to begin with. What makes you think the builder is capable of solving this mess. Why aren't they out there with hammers and chisels figuring out what went wrong? It looks like the pool is less than a year old from the plants and the unfinished retaining wall.

Although the steel job is minimal, I would guess the shotcrete application is the biggest problem. It could be any or all of the following: slump voids, weak mix, poorly timed application, poor curing. The only way to figure it out is to start tearing into it. Its usually best to know what is wrong before you plan on how to fix it.

This is the kind construction management and workmanship that gives our industry a bad name.

Compare the steel work with the pics in the thread 'new pool build in So Cal'.

renovxpt,

You say a very strong statement. This is substandard, that is and so on. The steel work has been commented on but you added blanket statements about the plumbing, excavation, and gunite that had little substance to back them. Care to back them?

Scott

Sure Scott, The following is based upon the pictures in this thread and represents my opinion. I could not find the build thread.

Excavation: It appears that there is very little finish work in the excavation. The walls were not chipped down and there is loose dirt on the floor and in the coves after the steel is in place. It looks like the operator didn't want to get off his machine and if he had a helper they didn't want to pick up a hand tool. The forming is also very minimal. Having an accurate excavation is an important begining. Everything else follows.

Plumbing: The pipes and fittings are not trenched in. There is a lot of flex being used. Its sloppy. The spa drain plumbing appears to have side drains and is just laying on top of a loose looking subgrade. They have deadended one jet and the whole manifold is not secured to anything, its just laying in the steel. Its hard to see how the main runs are handled. It does not reflect a lot of pride and craft. It appears that they were in a hurry.

Steel: As previously discussed the steel is very minimal. It appears to be ungraded #3 throughout. It follows the excavation which takes away from the normally crisp look that you see in a good steel job.

Shotcrete: In the one photo of shotcrete in process, it looks like they already have areas that have dried a while that still have to patched into. Not sure why they picked that time to do the spa and in general it looks like their timing is off. A good shotcrete job is all about timing. When marginal things happen during shotcrete the best insurance is a good curing process and I don't see any evidence of soaker hoses or sprinklers or a good curing process in place.

Tile: It appears from the abundance of calcium carbonate that there are a lot of voids behind the tile. These areas are not just scattered on the spa dam wall but also on the pool waterline tiles. My guess is that most of this tile will be falling off in a couple of years.

Thats how I interpret these photos.

They didnt bother to stone the pool, and if it rains on red clay you have a huge mess. They didnt bury the plumbing, instead laid steel right on top of it. The use of flex loses points with me, and they've got plenty. Calcium is also leaching out of the edge damwall.

What is the purpose of having two pipes going to two drains? If they needed more drains for additional pumps, they should have put them in.

Mike, How do you find the build thread? When I search ncrealestateguy nothing comes up. Who built this pool, it looks like a Sylvan or Blue Haven job.

I assumed that the dual drain pipes were for entrapment relief. Not having pots or sumps on the drains is dangerous enough, if they have multiple pumps hooked to those lines it really increases the hazard.

Why did they run the cleaner line around the pool? It looks like the machine operator was too lazy to move the stuff out of the way and the plumber didn't have any 45s. There is no pressure test on the plumbing? I don't see a chop saw anywhere and guess the plumber used a hacksaw which means he probably didn't debur the cuts. Judging from the taped off pipe in the pictures, his cuts are far from square.

The whole job looks like there was no plan or quality control.

The build link is below. Too bad some of the builders on this site had no comments during the build.

Here is a link that might be useful: pool build

All of the four PBs that I interviewed were quoting rebar, 12" OC. Is this not the norm? Seems like plenty of pools on this forum have the same.
It seems that not all readers understand where the cracks are... If you are looking down on the spa fro a birds - eye view, and the spillway is about at the 12 o'clock position, and the step is at the 6 o'clock position, the cracks area at 4 o'clock, and at 8 o'clock. There are no cracks near the face of the spillway, nor near the bond beams.
The spa was dug down to the original grade, even though it seems that the back one third of the spa has settled a bit, causing the two cracks.
I appreciate the feedback about maybe not enough rebar being in the spa, but I do not care if the plumbers used a chop saw or a hack saw, nor do I care now if flex pipe or rigid pipe was used. I would really like to know if the proposed repairs will work or not.
My main questions are:

1. Does the recommended process for the crack repairs seem ok? If not, what should I expect?
2. Does gunite create "cold seams"?
3. Is it ok that they are only chipping away the first 6 inches of the old pebbletec?
4. Will the new pebbletec adhere to this gunite patch stuff?

This is a pretty good website for your situation. They also offer repair suggestions.

Here is a link that might be useful: cracking up

nc, i so feel for your situation.
the only one of your ?s i can answer is "...were quoting rebar, 12" OC. Is this not the norm?" the standard contract from my PB was '10"OC with 5"x10" in stress areas' my pool is very basic with just a 6' deep end, (nothing like the huge drops that you have) and the rebar was best of luck with the repairs

Our minimum steel detail is 10m 8"oc both ways, 10m beam ties 12" oc, 4 - 15m bars in beam. That being said there are different standards everywhere and I never comment on structure in build threads unless the poster asks specifically for input.

As to your questions:

The recommended repair does not address the cause of the problem.

You will be creating cold joints, but gunite cold joints are not as concerning as poured concrete cold joints

They need to remove enough plaster material to create room to work

Yes, the plaster material will bond to the new gunite

renovoxpt...thanks for the link. I really think the soil that the tub is on has settled a bit.

Cascade... thanks for the input. If the cause of the problem is the tub resting on soil that is not original grade, what would be the best solution?

Also, they are suggesting that before the new pebbletec is shot, that they would seal the entire tub with that stuff that they use to repair minor cracks. (I do not know the technical name of this stuff). Will pebbletec adhere to this stuff?

Unfortunately, if the soil under the spa is moving already it will continue to do so.
It may be possible to inject grout or epoxy under the structure to support it (slab jacking) but again, the structure will be perched on unstable soil.
Was a soils engineer involved in the project? Perhaps your first step would be to contact him or another soils professional familiar with the conditions in your area.
As much as it probably hurts to hear it, in my opinion the only "correct" solution may be to remove the spa, excavate to bearing ground and start again. Sorry.

If its the soil then the rest of the spa is probably hanging over a void. You could tear out the bottom of the spa and install a pier system. Are the cracks wider at the top? it doesn't appear that way in the photos.

This is one of those jobs where an engineer should have been brought in to design the raised spa, steel, raised bond beam and probably for a soil test under the spa. You can't build a pool like this, the way that you build every other cookie cutter you crank out in mass. When a spa is that high out of the ground, you should pour a footer under it. I agree with the others about the plumbing and steel issues as well.

The Pebbletec will adhere but you are essentially getting a replaster job. Although I am sure some will argue, it is my opinion that a replaster job is never the same as the original plaster job.

Make sure you document everything they do and get amended warranties, extending them and guaranteeing the fixes.

What color is your pool? Is it Pebble tec or Pebble Sheen?Thanks.

that site for pool cracking is very informative...
thanks for providing it
makes good background reading...

how does one know when a soil engineer is necessary because you know most people don't get one when designing a pool...
we have yard that has slope because dirt was trucked in to raise elevation out of flood plain--this house has a piered beam foundation with piers sunk into ground under the slad...and has clay soil from what we can see in the flower beds...

people on each side of us have basically the same situation and both have pools ...and don't think they had a soil engineer in ...
so how would you know???

Color of the pool is Carribean Blue Pebbletec, which looks nicer now than what the pics show, which were taken right after fillup.
Renovxpt, the width o the cracks are so small, that one can not say if they are wider at top thatn at the bottom.
We are going to have a soil engineer to evaluate the soil and install a crack gauge. If the soil is fine, then I suppose we move on to a structural engineer to suggest a fix.

It could be a shrinkage crack. If it were my job or home, I would remove the brick and tile and expose the crack to see what is there. Then you can start to diagnose the problem.

You said the shotcrete crew had equipment problems and from the pictures, it looks like they shot the spa with the last half of the first load. Its very possible that the mix was too hot by then and they watered it down to get it to pump or lots of other possibilities.

If you expose the crack, you could determine how strong the concrete is, what kind of voids might be there, how deep the crack is and a host of other info that could guide your decisions.

loves2read, Most residential pool jobs do not have core samples done because an experienced builder/excavator can usually make a good assesment of site conditions. In your case it might be wise to pay 1k+- to find out what kind of fill is there and whats under it. Most developers are not too concerned about the fill that goes into your backyard and will quite often put the non-structural or marginal dirt there.

You can go buy a probe an poke around, you might learn alot.

loves2read, my structural engineer signs off on geotechnical as part of his requirements. If the ground is abnormal, he requires that we bring in a geotechnical engineer for a separate report. To second what renovxpt said, my structural engineer generally trusts me to make the call on whether he needs to see the hole before we do forms and steel

would the soil survey done for the piered beam foundation be something that would provide information so a pool builder could tell if an engineer was needed...

I am sure the builder did not truck in anything special--the dirt in our front flower beds and the yard is pretty bad--clay--stays pretty wet--we have added some compost with green sand and organic but probably should have taken out a foot of the beds and added couple of inches of decomposed granite before adding compost mix back into the dirt

It would be useful information and you should provide it. Some people might hold it back fearing it would drive up the cost. Go figure.

I am having a similar problem with my spa. I live in Central Texas with heavy clay soil as well as hard water. I just contacted our pool builder about 10 days ago and we are going on their schedule. We reported horizontal cracks in the spa last year with calcium building up in them. They came out and inspected and said it was normal and nothing to worry about. Now, the spa has a vertical crack going from the seat to the waterline completely through the wall. The spa drains into the pool overnight so the crack is completely visible now appears to go completely through the spa wall.

The pool is going on its fourth summer so it is relatively new. I also have a lot of calcium deposits all over the PebbleTec on walls in the pool with very few on the floor of the pool. I have not seen any cracks forming in the pool walls. However, the concrete patio has hairline cracks in several places going the full width of the patio. Do the calcium deposits indicate an underlying problem with the plaster or gunnite and will the cracking patio have any effect on the pool?

Soils reports are required by the International Building Code for swimming pools. Your cracks are structural. The cracks could be the result of the clay soil putting pressure on the shell. Your cracks in your deck are a good indicator of what is happening to your pool. Without proper steel surcharge engineered from the recommendation of a soils engineer the concrete does not have enough resistance to keep the expansive soil at bay. I would call a soils and structural engineer out for guidance, no crack is normal in a pool.

Soils reports are good for proper reinforcement for hardscape also.

Here is an example of an under engineered pool. The soil was an expansive clay. When the clay got wet the soil put enough pressure on the shell it cracked right where the rebar is located. Notice the almost perfect 12" O.C. cracks. This pool was part of an insurance claim I went and looked at and had to write up an estimate on. Insurance doesn't cover improper engineering. Pool was a total tear out.