by Nancy C
The pool leaked under the flagstone for some time on my spacious patio. The stones sound hollow and there is white residue on top of the decaying grout. Chlorine I figure. (I thought it was acid rain.) After I fix the pool leak. Some of the flagstone is as long as four feet and the problem stretches 50 feet. It has affected approximately 1/4 to 1/3 of the patio. After I fix the pool leak. Do I need to pull up all the hollow sounding flagstone and let it dry. Or can I remove the decaying grout let it dry for a couple weeks and replace it the grout?