NEW Build with hollow sound in OK flagstone coping

[tssklsimpson]

Need some advice on new build !

Have had several problems with quality, PB has been out 6 times to correct horribly set tiles and I suspect that coping is also an issue. I have OK flagstone and after install (2 weeks ago) I have noticed a hollow sound when tapping on about 50% of the stones. After reading some of the forum posts I suspect that the flagstone has not been set correctly. I am tapping the stone with a wooden broom handle and hear a distinct hollow sound and have also observed that the stones vibrate under foot. There also seems to be a fine crack between the mortar and the stone at the tile mortar/ grout line on the pieces that are hollow/vibrate. The solid sounding stones do not vibrate or have the fine crack at the tile line.


Should I be pressing the PB to reset the stones in question prior to the plaster being installed? I wonder if I am being to picky at this point due to all of the other issues that have been experienced thus far.

Thanks,
Scott

 

[Charlie_R]

I'd ask that it at least be checked and explained, and if it is done wrong, fixed.

 

[bmoreswim]

We have flagstone coping on our pool. When the tile/coping crew was building up the level of the bond beam (it needed to be higher after the autocover track was installed) they put a good layer of mortar down that the coping would go on top of. On ours, this layer didn't adhere well to the bond beam in many areas (which was evidences by the exact same method you employed). I was very worried. When they came back out to do the coping, I was there and pointed this fact out. Before doing the coping, they cracked out all of the offending mortar, laid a new bed and then installed the flagstone. No issues or funny sounds on the final product.

I would definitely say if it sounds hollow it didn't properly set/adhere onto the gunite and all such areas should come up.

 

[tssklsimpson]

Thanks for the feedback