Repairing pool immediately upon finish

SpaceDog

Member
Oct 9, 2018
23
Cary, NC
We opened our pool yesterday, but not before finding that the concrete in the deep end has already collapsed. Pool company is claiming that there must be a water source beneath.
They intend to repair in a few weeks, but I want to be sure that they do what they need to do and we don't have a recurring issue.

In addition to the collapsing concrete we have these issues, and I don't know whether they are common or concerning:

The bottom is not smooth, there are several pea-sized bumps along the bottom of the pool.
One in particular, near the steps, is sharp enough that we are concerned in time it will puncture the vinyl.

We have steel external steps that are covered in vinyl. The vinyl is pretty tight on each step, but has a loose tenting at the corners of the top step. Not sure if this should be tighter or if this is normal.

Any advise is appreciated. I want to get this right before they wash their hands of the pool.

Thank you,
John
 

SpaceDog

Member
Oct 9, 2018
23
Cary, NC
This is a brand new pool, the dig started in August. They did not hit water nor was water apparent to them when they did the initial dig. We dropped 2 feet with a retaining wall and then another 8 feet for the deep end.

For a few weeks the concrete was in optimal weather conditions. Then we had the outer bands of Hurricane Florence which filled most of the deep end. This water was pumped out shortly thereafter.

Upon returning for the vinyl phase, the concrete was disrupted. We had massive damage at the base of the deep end and at the edge of the shallow end. They were supposed to install the vinyl on Thursday, but were delayed and made no progress. Friday, but left the site at noon and didn't return. Saturday morning they returned and the vinyl was installed at some point in the afternoon. The concrete was apparently repaired with vermiculite which I was advised was fast drying.

The major damage/structural problem runs along the wall of the deep end at the far side away from the house from roughly halfway through the deep end to the back wall. You can see the and feel the separation.

They indicate they've never seen anything like this but they intend to repair. Given the experience we've had, I'm concerned about the repair being done properly and that all issues will be tended.
 

JamesW

TFP Expert
Mar 2, 2011
16,537
You probably had a lot of ground water during the storms.

I suspect that they are going to have to pull out the liner or at least pull it back to access the vermiculite.

If the light and fittings are all installed, that's going to make the job a lot harder.
 

SpaceDog

Member
Oct 9, 2018
23
Cary, NC
Thank you, James, for your feedback.

My understanding is that they will empty the pool and remove or partially remove the liner to repair.
My bigger concerns are these:

Will the repair take or will this problem persist

and

Are the other "imperfections" indicative of a problem.

I don't care if I have tenting at the step corners as long as this is to be expected and won't cause issues with the liner.
I don't care if I have pea sized bumps along the bottom as long as this isn't an indication of a greater problem and won't disrupt the liner.

I am concerned about the one bump that feels sharp by the stairs and whether it could eventually pierce the liner.

I probably wouldn't be as stressed about the minor stuff if the process and the major issue weren't a factor.
 

JamesW

TFP Expert
Mar 2, 2011
16,537
It's hard to tell about the stability of the bottom. If it's done correctly it should be fine.

The liner should fit correctly everywhere. There shouldn't be anything that feels too tight or too loose.

Steel steps are tricky. As long as there's no excessive tension in the liner, it's fine. A little bit of looseness is better than too much tension.

Debris under the liner should be close to nonexistent. Nothing big or sharp should be left under the liner.

Mostly, if it doesn't seem right, it's probably not.
 

SpaceDog

Member
Oct 9, 2018
23
Cary, NC
Thank you again.

We are definitely "not right". I got in again last night with the goggles and there has been more deterioration in the last 24 hours along the bottom and even on the opposite side from the major issue.

I suspect the contractor for the final phase of the project didn't do what they were supposed to properly. There is too much going on for this to have been done right.
 

JamesW

TFP Expert
Mar 2, 2011
16,537
They're probably going to have to remove the liner and cut out the bad sections of vermiculite and redo them.

Reusing the liner might not be possible. Once you cut in the returns, skimmers, steps and light, you're not going to be able to get them to line up again.

The vermiculite mix might have been too thin or maybe not mixed correctly causing a weak floor.

A lot of ground water could have been a contributing factor.

Another possible issue is what condition the floor was in before the vermiculite was installed.

Check the vermiculite when the pool is drained. Look for good thickness and strength. The mix should be strong and not soft or crumbly.
 

SpaceDog

Member
Oct 9, 2018
23
Cary, NC
Thank you, that's what I was suspecting.
On the one hand, at least it's still their problem.
On the other hand, if they don't think to re-order the vinyl before starting, we may be looking at a concrete hole again for some weeks.

I just want it right.

I appreciate your help James, and I'm thrilled this resource exists. Although the situation it terrible, understanding what is going on from an unbiased 3rd party really helps a lot.

Thank you.
 

JamesW

TFP Expert
Mar 2, 2011
16,537
The vermiculite should be between 1-1/2" to 2". If it's thin or weak, it should be removed and replaced.

If the damage is extensive, it might indicate a compromised bottom that should be redone.

They should have put the liner in fairly quickly after the bottom was done to reduce any risk. Ideally, the liner should be done the day after the bottom is finished.

I suspect that they might want to drain and then crawl under the liner to patch. This is a lot cheaper and faster than replacing the liner and bottom.

Hopefully, they do the right thing. If they inspect the bottom and determine that it should be replaced, then that's what they should do.

In my opinion, I think that I would want the liner and bottom removed and replaced based on the extensive damage.

The floor should be redone and the liner installed the next day.

The builder will probably not want to do that. They will probably try to get out as cheaply as possible with some patching and a promise to fix anything else that comes up under warranty.

It's hard to tell if the bottom definitely needs to be replaced or just patched.

When they start removing the bad vermiculite, get a few pieces for examination to check thickness and strength.
 

SpaceDog

Member
Oct 9, 2018
23
Cary, NC
Finally had the repair. The primary concrete needed to be redone. They used a different type to hold back ground water.
Looks better now, hoping it will hold.

Of course it turns out they didn't install enough drains or returns for our setup, but that's not something that can be easily remedied.
 

SpaceDog

Member
Oct 9, 2018
23
Cary, NC
The whole liner came out and was reused. I don't see any flaws in the liner.
The primary repair was in the deep end with a major crack repaired. They resealed the whole of the pool though, and smoothed out the bumps and divots that had formed.