Coping not flush with surrounding concrete slabs, coverup of prior damage?

[larrynburris]

Hello everyone,

You've got a pool newbie here. I purchased a home with a pool last June. The pool was described as having a brand new liner. As part of the closing process, we hired a pool inspector because we thought it was strange that the coping edge was raised with a 'half-speed bump' shape leading up to it. Over the last year I have noticed that there are different styles of concrete that were used for the slabs that are around the pool. One is best described as rougher look and feel with small rocks and pebbles in it that is mostly what's visible in the picture. The other is the smoother concrete which you can see a little on the right side of the picture. The concrete leading up to the coping seems completely different than these two, feeling very thin and brittle.

Our pool inspector mentioned the deck condition on the pool inspection as:

Many cracks; Coping is raised several inches and a concrete patch is installed to tie coping with existing concrete

The rest of the pool was described as follows on the pool inspection:

18 x 36 28,000 Gallon Inground Vinyl Liner with 3 liner covered steps surrounded by concrete deck
White plastic/tooled expansion joints and aluminum coping
1 Hayward Skimmer Square Lid, 2 Wall Inlets, 2 Wall Returns
1HP Hayward Superpump and Hayward S244T Sand Filter using 1.5" PVC

When closing the pool, I installed a safety cover which was installed and under tension all winter. After taking the safety cover off, I noticed that the concrete slabs were separating from the concrete lip that meets the coping concrete. I have attached a picture showing the separation that I'm talking about. In one place, you can see that the coping concrete is breaking away significantly and you can see the steel structure behind the broken pieces. In that location, the concrete slab is visibly canted downwards towards the pool.



I have a handful of questions about this:

1. Is the coping concrete a patch that is indicative a problem that the previous owner / renovation contractor was trying to cover up?
2. Should the pool inspector have been able to diagnose and warn us about this?
3. Can anyone describe possible causes for the separation?
4. Given possible causes, what are the best courses of action for recovering from this?

Thanks for reading and any advice you can provide.

 

[zea3]

Hi, welcome to TFP! My initial thought is that this may have been an attempt to prevent rainwater from running off into the pool. Does it look like the yard is sloped toward the pool? I don't know if this is something the pool inspector should have noticed or not. If everything was intact before the winter cover went on, how would he have known without digging into the structure of the pool? It looks like a cosmetic issue more than a structural one.

 

[larrynburris]

Thanks for your reply zea3!

Around the concrete is are flower beds and beyond that the yard actually slopes downward where it is not flat. Rainwater is actually a concern of mine now because the concrete slabs that are shifted downwards toward the pool in the left side of the image cause rainwater to runoff under the coping edge and potentially erode whatever is underneath.

 

[bmoreswim]

Here's what I think happened...

All of the concrete decking has settled some and sloped inward towards the pool (not as much as it would seem though). When the vinyl liner/aluminum profile coping was replaced, they likely cut back the overhanging part of the poured in place aluminium/concrete coping and installed new coping higher up than it originally was (basically on top of the old coping). So as not to necessitate ripping out all of the decking. It was almost certainly an approach to get the pool looking pretty good without concern for the ultimate aesthetics or how one might go about making it look/work correctly after that was done.

So now what I think needs to be done is to see if the curb-shaped concrete coping can be cracked out from the aluminum coping profile. If it were to work and come out cleanly, or at least to not damage the aluminum, then the decking could then be ripped out, the ground properly compacted (and piping and other repairs done while concrete is out) and then repour the decking into the aluminum coping profile and with the appropriate slope away from the pool.

Bottom line, it's a great opportunity to have a fantastic looking pool area, albeit at considerable expense. But what good home improvements don't cost some good money. If you are handy, I could see this being a DIY (with friends) project that helps the cost side of equation significantly.

 

[larrynburris]

Thanks for the feedback bmoreswim,

I think that you have a pretty accurate assessment of how it played out. Do you have any idea how to estimate what the deck around a pool this size would typically cost?

 

[Pool Tool]

I agree with boreswim for the most part, except for the part of them repouring new coping, etc. My $.02; is while the decking sunk in the pool didn't move. The pool is a much more rigid structure and is much deeper than the decking support. When they replaced the liner they added the concrete ramp to create a transition in and out of the pool that would prevent people from breaking their toes.

Your inspector's note details kind of details that. But instead of the coping being raised, it should have actually said that the deck has sunk several inches due to poor compaction during backfill of the pool.

There are companies that can "lift" the concrete back up with mud or grout, i.e. mudjacking. But I don't know the feasibility of doing this near a pool. Replacing the concrete is likely your ultimate option. You will hear of concrete decks costing anywhere from $5/sq ft to $9/sq ft to even higher. That would not include demo of the old.

 

[larrynburris]

Thanks Pool Tool,

When I first made this post, I was considering the possibility of the previous owner dealing with pop out or something similar but I didn't want to influence anyone's opinions by including that in the description (I'm not sure if the previous liner was liner or not). I am thinking along the same lines as you where the concrete is settling rather than pressure pushing the pool upwards. There was as significant shift between last year closing and this year opening. In some places, the separation between the ramp and the slabs is around half an inch where there was no separation last year. There wasn't a safety cover on it prior to last year. Could the tension of the safety cover have caused some of the shift that I'm seeing?

 

[bmoreswim]

I think it just continues settling and is unrelated to the safety cover. With the decking sloped towards the pool, lots of water is flowing down next to the pool and going somewhere. And wherever water goes, it takes sediment with it, thereby making the sinking worse. I suspect it will continue to get worse and not stabilize until you resolve the bigger issue.

 

[Pool Tool]

I agree with boreswim again and add to that if there is clay below the decking it will move the concrete up and down and it swells with water and contracts as it dries out. The concrete anchors probably have no effect on the concrete, if the anchor was supporting the weight of the concrete they would likely just rip out of the deck.

 

[kimmielea]

My 2 cents… since I went through this.
2 years ago I replaced my liner and I also replaced the coping. I had the old aluminum "cinderella" coping. I had it replaced with a bullnose coping (like what is around your pool). Now the problem… The old coping slanted down and was just above the existing concrete, and the new coping was about 2" higher than the concrete. I ended up having new concrete poured.

Before with "cinderella" coping:

New Bullnose Coping:

After with new concrete:

 

[dw9000]

I would put a 4 or 6 foot level on that decking,, if it is running down hill towards the pool (check on all 4 sides in the middle), I agree with the above posters, the deck is sinking inwards and someone just built up the coping (or put concrete/putty) behind the existing coping and now you have a big lip.
If the level doesn't show severe inward slope (toward the pool) then you might have something different. Like the pool walls sunk in, they tried to build up the top of the walls and installed new coping too high? Or got lazy and just installed coping over the existing sunken coping??

Either way, if you want to pour in a an entire new deck (w/o removing the existing) you could probably do it for (ballpark) $4500. But you would have to remove that existing concrete from the back of the coping so you have a nice seam between the deck and the coping.
If you were to have to remove the existing deck and repour your looking at more like $6500-$7500+.

Either way, your decking near the edge (grass/flower edge) is going to be 3-5 inches higher because of this high coping.

Before I did anything I would want to make sure there is no more settling, which might lead me to removing of the deck and making sure the sub-base is packed