bond leak?

[boutselis]

I have a situation that I was told is called a bond leak. from the way it was explained, my pool was poured and then my deck was poured on top of the pool wall making the deck the top 4 or 5 inches of the pool.

supposedly over time the bond between the two pours has broken causing a water line leak. I took off a few tiles and ground off the mortar. I was expecting to see the seam where the deck and the pool wall meet but it looks seamless. I know I have a water line leak. but I was wondering if the leak is from the grout of the mosaic tile failing and water is just passing through the many cracked grout areas and then passing through the mortar and the cement pool wall? It doesn't seem like a water proof mortar is used on tile. Mine is very soft and came off pretty easy.

hopefully I explained it correctly

 

[Melt In The Sun]

How certain are you that the leak is at the water line? There is an article in Pool School here that gives some basic advice for pinpointing a leak's location.

Cracked grout isn't going to cause a leak...your tile could be completely gone and you won't lose a significant amount of water through the pool shell. Something else is going on.

 

[gwegan]

I agree with Melt above.

We need pictures.

If it was constructed as described it will almost certainally leak and it cannot be fixed.

Normally the water line of a gunite pool is about three inches below the top of the pool structure (bond beam). A cataleaver deck would be poured on top of that so the deck slides over the bond beam. Otherwise the deck and pool will Fight each other and cause cracking and buckling.

 

[boutselis]

I had a contractor friend come over and look at it. He looked at the area where I removed the tile and ground down the mortar. He noticed 2 different size aggregates. a small one in the shot crete (his words) and a large one in the pool deck pour. so he was able to point out right where the bond beam was. He says the portion of the deck over the pool is only 2" thick. thats why I have a uniform crack all the way around my pool on the deck .

So if the thickness of the deck poured on the pool wall is relatively uniform then that couldn't be the leak because its too high.

He also notice that the crack in the deck is level on each side of it except in one spot. right by the skimmer. So the deck sunk down a little right by that spot. the skimmer looks solid but I.ve been told looks can be deceiving

I'm going to take off the rest of the tile and try and get some pictures up. As to the position of the leak. The water stops leaking just at the bottom of the tile.

 

[gwegan]

Normally the top of the tile line is the top of the bond beam and the deck is poured above that. often with something between so the move independently. This doesn't apply if you have a coping on top of the bond beam, then the coping is attached to the bond beam with mortar.

We really need pictures to be of much assistance.

 

[boutselis]

I was originally looking much lower for the bond because I had a pool guy telling me it was close to 6" down. Now that my friend pointed it out to me I feel stupid for missing it. The deck was poured just thick enough to me covered by the top 2" bull nose tile. Looking at the picture now I'm worried it doesn't show you enough

 

[chiefwej]

I would be looking very carefully at that skimmer and the area right around it. What you are describing would have put a lot of stress at that skimmer location.

 

[boutselis]

Here is what the crack looks like at the skimmer. surprisingly not 1 of FIVE pool refinish companies even pointed this out. Though I'm not certain its significant. the crack goes all the way around the pool and is pretty uniform but this is the only place its un even

 

[gwegan]

WOW

That crack runs around the whole pool?

Could you post more pictures.

from further back and showing the tile.

Does that seam in the pool wall under the skimmer extend around the whole pool?

I have some thoughts but I'd like to see more pictures.

 

[boutselis]

What do you mean by seam in the pool wall under the skimmer? Do you mean where the deck and the pool wallet like I showed in the first picture? I would have to remove the tile there to see but I think it does

yes there is a hair line crack pretty much around the entire pool about 5 inches from the edge.

 

[gwegan]

So as I see it you have several problems that is caused by the faulty design of the pool and deck interface. You are experiencing two different results of the same design defect.

The faulty design is this: Gunite pool structures are homogeneous masses of concrete. They act like a large rock. Because they have water inside they are relatively stable rocks. Most of its surface area is burred. That means pools don't change temperature quickly and don't change size quickly. They change and move, they just do it slowly. Your deck on the other hand is a large flat surface relatively thin structure with a great deal of area exposed to the sun or to the cold. The deck is flat so most of its movement is horizontal.

With that background, it appears here is appears a number of mistakes were made. First it appears that the deck was laid directly over the bond mean and the deck is apparently thicker outside the bond beam than on top of the bond beam. That means it does not slide over the bond beam as it expands and contracts. It pushes against the pool every time it expands. The crack five inches from the edge of the pool is just above the outer perimeter of the bond beam. Stress there is causing the crack.

Second the crack by the skimmer access is a no brainier. Unless you are really good and use high strength concrete, you need at lest two opposing control joints on either side of a solid round penetration. The concrete knew the rule and created its own second opposing control joint -- a crack.

Third your tile problem. Because the deck is laid over the pool its acts seperatly from the pool. So the tile cracks and falls off.

For this to work you needed to pour the concrete over the bond beam seperately from the rest of the deck with a large control joint between then. A concrete coping actually. Then the concrete coping would act more like the pool. It would eventually fail but the lifetime would be greater. The tile over a joint between two very different structures will fail but with careful construction you should be able to get 10 years of life.

I don't see a way to repair this, only replace and crate a concrete coping over the bond beam.

 

[boutselis]

none of the tile is falling off. But I think that may be because there is a 2" tile at the top, and it seems a grout line is at the seam of the deck and the pool and then the 6" mosaic is below that on the pool wall. So no piece of tile seems to span over the area where the pool wall and the deck meet.

here is a picture of the inside of my skimmer. the water stops dropping right at the bottom of the skimmer. to me it looks like it could be leaking here

 

[PoolguyinCT]

I can't see the pics - but based on the read I would look hard at skimmer to wall interface.

 

[boutselis]

the pictures aren't showing up?

 

[gwegan]

They are for me.