Gunnite Problems

Our pool is less than 10 years old, and has had several long cracks in the plaster since we bought the house, 5 years ago. We have the cracks tested regularly, and have always been told that they aren't leaking, it is just superficial cracks in the plaster.

This year we decided to have the cracks repaired. When the contractors cut out the crack they found that the gunnite had turned into the consistency of wet sand. When the surrounding plaster was hit with a hammer, it was obvious there were hollow voids under the plaster.

Obviously, some water had been leaking through the cracks, but I wouldn't have expected the gunnite to just disintegrate like this? Is this normal for gunnite when it gets wet? Or did the original pool contractor screw up?

Our contractor thinks they can repair the pool, but every hole they've dug has shown the gunnite to be the same consistency. If they continue digging, they have to remove at least 1.5" of gunnite to get back to anything solid. The holes quickly fill with water shortly after.

I'm concerned that any fix may be very temporary, and that the pool shell is not stable enough to be repaired.

Has any one else had this experience? Could the pool be repaired or should I think about ripping it out and starting again? :(

Jim

Gunite is just cement without the stone (aggregate). It sounds like the gunite in this area was improperly mixed when initially installed. Patch it an don't worry about it - but check the rest of the pool for hollow spots while your in there. Hopefully it was just this one area.

Thanks Mschumack.

We've had a couple of core samples taken and it looks like it is poor quality gunnite and is isolated to about 1/3 of the pool. The gunnite appears to be in two layers (two applications?), the bottom one is fine, it's the upper one that is bad.

We're going to have the plaster removed from the problem area and the bad gunnite repaired.

Jim

Removing the plaster to inspect and address the gunite platform is your best avenue.
I wouldn't sweat this at all, I'm sure that your contractor has dealt with situations like yours before.

See Ya,
Kelly