Empty fiberglass built in pool - side rupture..question

[David Nasser]

Is it common for a built in fiberglass pool's sidewall to
rupture if the pool has been empty for over a year. The pool's
is 9ft deep.

As I walked on the surface of the pool I could feel the
fiberglass crunching as I walked.

David

[Barry Adair]

DO NOT DRAIN YOUR POOL
Your fiberglass pool is designed to remain full of water at all times. If the pool is drained without proper directions, hydrostatic or ground pressure outside the pool could cause the structure to buckle or crack. All damage to the pool shell resulting from improper pool drainage is the owners responsibility. If it becomes necessary to drain the pool, contact your Dealer or Pool manufacturer.

installed for san juan, parkhill & dolphin pools back in the day

Anyone having swimming pool, hot tub or spa problems with their residential or commercial properties is free to contact me at 972-487-5634

[Robert Ernst]

Barry is right on here. Even non fiberglass pools can be effected by hydrostatic pressure. Often in a concrete pool when work is being done a couple holes will be drilled in the bottom of the pool to keep the water from pushing it up. Hydrostatic forces can be 10x more than dirt alone.

[David Nasser]

Thanks Barry and Robert.....
That's the insight I was looking for.

[Randy L. Mayo, PE]

David

To add to what others have said, these pools can float up out of the ground if the soil gets saturated. As said NEVER DRAIN A POOL without some input from a professional.

[KEVIN WOOD]

Don't forget the uv damage also can break down the lining of the pool if it does not have protection on the bottom with water.

[Pete Campbell]

For every action there is an equal and opposite reaction.