Need urgent help with cracking/leaking pool on a hillside in Austin, TX!

JamesW

TFP Expert
Mar 2, 2011
21,129
I think that the biggest issue is that the pool was built on about 8 feet of fill that was totally unsuitable.

In my opinion, the design is critically flawed.

You basically have some structurally unsound walls filled with random dirt/sand/construction debris and then a very heavy load placed on top.

So, you have a pool being supported 8 feet above the ground on a perimeter wall that was never designed for that type of load.

Most of the wall is in compression (vertical force) and the wall is beginning to fail as evidenced by the cracks.

If the load shifts horizontally, the risk of catastrophic failure goes up substantially.

In my opinion, there's no way that you could find any engineer who would consider the current construction to be structurally sound.

Can a retrofit support system work?

Maybe, if it's done correctly, but I would want an independent engineer to evaluate the current construction to determine if reinforcements will work and if they will, design a proper plan.

I suspect that the current plan is the least effort possible to install some piers at the lowest cost then replaster and hope for the best.
 

Arizonarob

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Mar 25, 2018
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Chandler Arizona
After seeing all those cracks closer, and hearing what James and Brian had to say, I’m going to say there is no way I would want that “elephant in the room” outside my back door. IMO I would want a complete tear down and rebuild.
That absolutely stinks that it needs to happen, but you’ve spent your hard earned money on that property and you want it done correctly!!
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
20,474
Northern NJ
Have to support the back wall with a retaining wall built up along it or by braces at a 45 degree angle down to the grass area and into the bedrock.

At some point it becomes better to start over than a bunch of fixes to the pool base with piers and supporting the back wall.
 

bdavis466

TFP Expert
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Aug 4, 2014
5,529
San Clemente, CA
The problem with any sort of retrofit is that no engineer or contractor truly knows what is there to begin with. I certainly wouldn't want the liability and anyone throwing an idea for a solution at the existing pool is basically taking a shot in the dark.

If it were mine my only plan of action is to get what I could out of the Builder(s) and start over with a pool that is actually engineered for the site conditions.

The retaining wall that the pool was built on top of probably wouldn't even meet the requirements of retaining the fill, not to mention that there is a pool with a freestanding wall sitting on top of it.

Honestly I think any sort of retrofit that you do to this pool is going to be a waste of time, money and emotion.

The expense of redoing the pool is probably sickening but I bet it will end up being the most economical option when you consider what you are more than likely going to face down the road if you keep trying to retrofit the pool. you also need to consider that the Builder is only going to be willing to do so much until he stops answering the phone. Truthfully I'm surprised that he still willing to work with you at this point.
 

JamesW

TFP Expert
Mar 2, 2011
21,129
I agree, remove the pool and rebuild it correctly.

Trying to retrofit is going to result in a neverending saga of stress, worry and frustration as the piers are installed, then cracks and leaks and then draining and going through the exact same process over and over.

And, that's hoping that the wall doesn't catastrophically fail and the pool goes tumbling down the hill with everyone in the pool.
 

bdavis466

TFP Expert
Platinum Supporter
Aug 4, 2014
5,529
San Clemente, CA
I would say that's highly unlikely because I don't think it's possible to build a house and not have it adequately engineered. It's a little baffling to me that they were able to get the pool in this state without engineering and permitting but who really knows what happened behind the scenes.

I know there are rural areas where pool permitting isn't a concern but I can't imagine that being the case with an actual dwelling that people live in.
 

JamesW

TFP Expert
Mar 2, 2011
21,129
I suspect that if the walls buckle, the pool will fall straight down and hit the backfill or tumble down the hill away from the house.
 

PoolGate

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Jun 7, 2017
4,963
Damascus, MD
I would say that's highly unlikely because I don't think it's possible to build a house and not have it adequately engineered. It's a little baffling to me that they were able to get the pool in this state without engineering and permitting but who really knows what happened behind the scenes.

I know there are rural areas where pool permitting isn't a concern but I can't imagine that being the case with an actual dwelling that people live in.
If this was a new subdivision the contractor can get away with a lot more. There may have never been an inspection. Usually on larger projects the inspector inspects 1 in 10 homes and if a significant amount of pools, the same. The fact that the builder insisted on a specific pool builder kind of says they were "pre-approved" by the inspectors.
 

atxneedshelp

Member
Nov 3, 2018
12
Austin, TX
Hi all.

So we live outside of the city limits so the pool was permitted but only through the water district. The water district approved the plumbing on the pool! There was no permitting for the structure component (would have been if we were inside the city limits).

The builder (and their structural engineer) wants to add eight 18" piers with wide capitals on top (like maybe 3'x3' square capitals on top of the piers to help distribute the support more evenly). They would dig down through the pool, through the fill, and down into the rock. The rebar from the piers would connect up with the existing pool structure. Four piers would be under each corner of the hot tub and then four more over by the steps/tanning ledge area, evenly spaced. The purpose is because their structural engineer is concerned that the pool did not have a wall supporting it on the edge by my house (opposite the faux infinity edge) so they think it is shifting more towards my house. They believe these 8 piers could support the weight of the pool and that the fill underneath would serve no purpose. They would seal around the metal grab bars in the pool and re-Pebblesheen it too.

I do not know if the pool builder had engineering plans initially but my guess is that he didn't since the home builder won't give them to me and someone said no structural engineer would have engineered it like that. We would get the engineering plans before proceeding with the piers though if we go that route.

I would love to just get the money from the builder for all this work and then demo the pool and re-build but the cost of doing so would be so expensive! The money from the piers might not even cover the demolition of my pool!!

My builder doesn't think I could get anywhere with the pool builder's insurance (1 year on faulty workmanship and it is past that and he said they would just fill the cracks as part of the gunite shell 15 year warranty).

The structural engineers we have spoken to and brought out to our pool all have varying opinions too. The interesting thing is during the build, they went back and added "staples" to connect the floor and that back wall better. I am not sure how they got the idea that it wasn't structurally sound so that they should cut through the gunite to install those staples. I feel like there are many back stories that we don't know about.
 

kimkats

Mod Squad
LifeTime Supporter
Jul 10, 2012
47,063
Tallahassee, FL
So they will take out all of the plaster, punch holes in the shell all over the place, put in the piers and hope that back wall stays up.

The staples-I saw the pic with them in it....What did they connect the staples to when they did it? Was it just to the concrete or did they go all the way to the rebar?

Did any of the engineers look at your pics? My main concern is the steel (or lack of steel) in the back wall to the floor. They should be able to look at your pics (thank goodness you took them!) and know if the steel is enough to hold that wall up.
 

PoolGate

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TFP Guide
Jun 7, 2017
4,963
Damascus, MD
Hi all.

So we live outside of the city limits so the pool was permitted but only through the water district. The water district approved the plumbing on the pool! There was no permitting for the structure component (would have been if we were inside the city limits).

The builder (and their structural engineer) wants to add eight 18" piers with wide capitals on top (like maybe 3'x3' square capitals on top of the piers to help distribute the support more evenly). They would dig down through the pool, through the fill, and down into the rock. The rebar from the piers would connect up with the existing pool structure. Four piers would be under each corner of the hot tub and then four more over by the steps/tanning ledge area, evenly spaced. The purpose is because their structural engineer is concerned that the pool did not have a wall supporting it on the edge by my house (opposite the faux infinity edge) so they think it is shifting more towards my house. They believe these 8 piers could support the weight of the pool and that the fill underneath would serve no purpose. They would seal around the metal grab bars in the pool and re-Pebblesheen it too.

I do not know if the pool builder had engineering plans initially but my guess is that he didn't since the home builder won't give them to me and someone said no structural engineer would have engineered it like that. We would get the engineering plans before proceeding with the piers though if we go that route.

I would love to just get the money from the builder for all this work and then demo the pool and re-build but the cost of doing so would be so expensive! The money from the piers might not even cover the demolition of my pool!!

My builder doesn't think I could get anywhere with the pool builder's insurance (1 year on faulty workmanship and it is past that and he said they would just fill the cracks as part of the gunite shell 15 year warranty).

The structural engineers we have spoken to and brought out to our pool all have varying opinions too. The interesting thing is during the build, they went back and added "staples" to connect the floor and that back wall better. I am not sure how they got the idea that it wasn't structurally sound so that they should cut through the gunite to install those staples. I feel like there are many back stories that we don't know about.
This is encouraging. It looks like they are willing to go to the mat to make this pool safe. I am not a structural engineer and don't even play one anywhere so I won't comment on the solution. I will suggest you ask them to pay for an independent structural engineer to evaluate their plan and bless it. What they are suggesting sounds quite expensive so I would think they'd want all the input they can get.
 

JamesW

TFP Expert
Mar 2, 2011
21,129
Have you checked the credentials of the engineer to verify that they are actually licensed and qualified?

The plan sounds weak, at best.

I think that you need your own qualified engineer to advise you.
 

Arizonarob

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Mar 25, 2018
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Chandler Arizona
Yeah I agree with James. There is no way I would let anything move forward until I had an independent engineer hired by you evaluate the plans.
 

JamesW

TFP Expert
Mar 2, 2011
21,129
I think that the staples were added because the concrete was beginning to crack almost immediately.

You have a pool sitting 8 feet above the ground being supported by 3 wall that are not strong enough to reliably support a pool full of water.

Putting in 8 piers seems more like show than anything.

Also, why didn't they do a real infinity edge?

It's a perfect location.

If you wanted to demo the pool, a few taps on the back wall with a sledgehammer should bring it down. Just be ready to run when it comes crashing down. And, get it on video. (Of course, don't do anything to the wall to damage it as it can be seriously unsafe).

I would suggest that people stay out of the pool and away from the back wall until it is certified as safe by a real engineer.

If you do remove the pool, then, you could build it right with a real infinity edge.
 

PoolGate

Gold Supporter
TFP Guide
Jun 7, 2017
4,963
Damascus, MD
Again, not being a structural engineer I have a question. Does adding piers do anything for lateral strength issues? It seems to me that maybe the piers would stop it from sinking if that is the issue but the horizontal cracking looks like that wall simply cannot take the weight of the water pressing against it.
 

aham23

Well-known member
Aug 8, 2018
100
AZ
definitely get your OWN engineer to inspect and opinion on what is wrong, why it is wrong, and how it should be fixed. if this home was a new build and the home builder hired the pool buidling then they have a vested interested here. the can be found liab for improper supervision of subs, breach of contract, ect... good luck.
 

atxneedshelp

Member
Nov 3, 2018
12
Austin, TX
I also think the piers will help with the vertical loads below the pool but they will not address the rotation of the outside pool wall which could be part of the problem... We did hire an engineer and he wants us to make a hole from the center of the pool to the bottom of the outside wall but I am not sure who I hire to do that?!? He said this will give us a good cross section of the construction thru the crack.

We didn't do a true infinity edge because we have little kids. I didn't want to risk one getting on a floaty and floating over the edge! It is scary enough with the edge as we have it. Plus, I didn't want the extra maintenance of having another pump and a lower pool, etc. And we have a lot of critters in our area so I don't want to invite them over to take a drink in our pool. I prefer to make them work at it to get to our pool. Also, our pool is close to our side yard so we didn't have any more room to build out (over the build line as it is so we had to get approval from the HOA) for a lower pool area for an infinity edge.

Any ideas on who I would hire to make the hole in the pool that the structural engineer is asking for?

Thanks!
 

JamesW

TFP Expert
Mar 2, 2011
21,129
Just Google concrete cutting Austin Texas.

What does the engineer think about the overall construction based on the pictures?