Shotcrete day - another quasi panic

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Not what I want to hear JamesW but what I expect based on everything else I've read. I don't see any meaningful recourse though...until it fails it's just dissatisfaction re: a sloppy job, right?

The PB offered to fix the missing bench area without prompting from me and he didn't try to charge for it either. I think he tries to do "the right thing" so I'm not really surprised...but clearly he's not using the best crews. I also think he's too friendly with his crews and not really representing my interests/pushing them to do better work.

He didn't respond to my report re: the area of the wall that got thin and has exposed rebar. I brought it back up with him and he said he'd have the crew to "patch it" and if they can't, "it will be fixed at brown coat time" and he mentioned according to the engineering the wall was only 6" (it is about 9 in that thin area and more like 11 everywhere else). It looks to me like they just didn't have a spacer in that corner so the backer board ended up going straight up against the rebar. Guess I have to read up on the process of shooting on top of existing material -- I don't like the idea that tile/plaster guys are going to "fix it" -- I assume there is a reason that rebar is supposed to be encapsulated in a couple inches of concrete so I'll try to get them to do that.

Soooooo wish I had done an owner-build and been able to hire my own crews...
 
So here is what you can do to further your cause................be there when the "fixers" get there. Have a breakfast/lunch laid out with a cooler full of water and Gatorade. Talk to them about your concerns and ask them to please, pretty please help you out. You have sweetened the pot so they might be VERY willing to go the extra mile. Should you have to do this? Nope but...........no one else is going to care like you do so take care of you and yours!
 
Well, they came back out to shoot the missing bench. They also shot a little more on the corner that was too thin with exposed rebar...not that I think they likely did any better quality work than the first time around but at least they made an effort.

IMG_7726.jpg

IMG_8278.jpg
 
JamesW said:
Gunite and shotcrete should give the same quality finish.

Any weakness is due to application processes.

The original poster's shotcrete does look a little bit sloppy.

Probably poor technique and maybe improper mix.

Apparently, there was extensive use of rebound and cuttings, which create areas where the concrete is not properly compacted and not dense enough.

I wouldn't be surprised if the pool gets some cracks.
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This is not correct. Gunite will always have a cleaner finish as it is composed of much finer material than shotcrete. Shotcrete is concrete. Concrete typically consists of 3/4" - 1" rock, sand, and cement. Gunite is sand and cement with water applied at the nozzle. Shotcrete will have a rougher looking finish versus gunite due to its composition.
 
Dry mix Shotcrete (sometimes called Gunite) and wet mix Shotcrete are both methods of applying concrete.

They both use the same concrete mix.

The difference is that gunite is sent down the hose predampened but not fully mixed with water. The water is added at the nozzle by the nozzle person.

Wet mix Shotcrete is mixed with water and sent down the hose mixed with water.

So, the difference is how the water is added to the concrete mix.

Both processes use the same aggregate. The aggregate is usually about 3/8". No aggregate should be larger than 1/2".

A cement mixture with only sand aggregate is called mortar. A pool uses a concrete mix and not a mortar mix.

https://www.concrete.org/Portals/0/Files/PDF/Previews/506R_16_preview.pdf
 
That isn't the case here. Shotcrete can be spec'd with whatever size aggregate your pump can handle.

Gunite is sand and cement. The only time I've seen aggregate added is when the crew specifically had the equipment to handle it and few do because the hose was so large and a 1500 cfm compressor was needed.
 
For the dry-mix process ACI recommends (gradation 1) aggregates no larger than 1/4 inch, for wet-mix (gradation 2) aggregates shall be no larger than 3/8ths of an inch.

How to Apply Shotcrete - AQUA Magazine
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So, this indicates that the aggregate is 1/8" smaller for gunite vs shotcrete maximum recommended aggregate size.

It's a relatively small difference and both methods use relatively small aggregate. I would consider 1/4" aggregate to be bigger than sand.

Shotcrete can use the finer aggregate mix or the coarser aggregate mix. Gunite should use the finer aggregate mix.

I would consider either mix to be concrete with aggregate.

In any case, you should be able to get a good finish on either shell if done properly. If shotcrete uses the finer aggregate mix, the finish should be about the same as gunite.

If shotcrete uses the coarser aggregate mix, then you might get a slightly rougher finish.

In this case, the concrete looks poorly done. It looks like the mix wasn't consistent, it looks like proper compaction was not consistency achieved and it's reported that rebound and cuttings were incorporated into the shell instead of being discarded.
 

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JamesW said:
Dry mix Shotcrete (sometimes called Gunite) and wet mix Shotcrete are both methods of applying concrete.

They both use the same concrete mix.

The difference is that gunite is sent down the hose predampened but not fully mixed with water. The water is added at the nozzle by the nozzle person.

Wet mix Shotcrete is mixed with water and sent down the hose mixed with water.

So, the difference is how the water is added to the concrete mix.

Both processes use the same aggregate. The aggregate is usually about 3/8". No aggregate should be larger than 1/2".

A cement mixture with only sand aggregate is called mortar. A pool uses a concrete mix and not a mortar mix.

https://www.concrete.org/Portals/0/Files/PDF/Previews/506R_16_preview.pdf
Click to expand...


Did you participate in 506?

There is only ONE voting members from p&s side.

- CMM 506 : is prefaced as a tool for subject matter experts, not the layperson.

*content also conflicts with a popular online questionable engineering “printer” often linked in threads.
 
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PoolguyinCT said:
*content also conflicts with a popular online questionable engineering “printer” often linked in threads.
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:laughblue: :laughblue: :laughblue:

Gunite and shotcrete are not the same thing here. I only know of one gunite contractor in my area and he is used exclusivity by one low budget pool builder... Likely due to cost.

Shotcrete is a superior product especially when "industry standard" less than ideal installation practices are used.
 
bdavis466 said:
:laughblue: :laughblue: :laughblue:

Gunite and shotcrete are not the same thing here. I only know of one gunite contractor in my area and he is used exclusivity by one low budget pool builder... Likely due to cost.

Shotcrete is a superior product especially when "industry standard" less than ideal installation practices are used.
Click to expand...

Regional nicknames aside, If it is shot it’s shotcrete and it’s all concrete.

Bdavis-
I knew you would get the laughs.

I think the moral of the thread story is OP is staring at hand packed rebound.

& I just cancelled my next 12 haircuts, I’m bringing it back!
 
kimkats said:
What is going to go over all of that in the corner in the second pic?
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You mean where it looks like there is a pile of loose concrete on that outer corner between spa and pool?

There will be a seating bench along the pool wall, level with the coping. Along the spa wall will be stairs. You might imagine it better in this pic:

IMG_6206.jpg

My build thread might have a more designy pic that would show it better but I’m on my phone and not sure how to link to it.

There will be a fire pit between the house (left side) and the spa. There will be a bench on the outside of the pool wall along that top stretch of pool in the pic, then just above that bench, the fire pit and just above that another bench (that one will have a back to it, not just a bench).

To the right side of the fire pit area will be stairs to the spa. You can’t be expected to dry off out in the cold after all!! Of course, the outdoor shower is just past the fire pit area so you could always go that route too. ;)

Just hope the pool shell holds together after this shoddy work that was performed.
 
bdavis466 said:
Any idea who the shotcrete sub was?
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Gold Coast Shotcrete

1a92167cb163a401a687b24850366c34.jpg
 
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