How do I make sure my pool doesn’t pop? Don’t fiberglass pools pop out of the ground at any moment? I get this question all the time. My answer. Fiberglass pools NEVER pop out of the ground. Concrete pools pop out of the ground…and they take the deck, the plumbing, and can even damage the house as they lift. I have become an expert in repairing fiberglass pools that are severely damaged after hydrostatic pressure has attempted to pop or float them. I have personally reconstructed the floors of such scenerios 14 times. In every case the pool was either drained and left empty for an extended period of time without addressing the possibility of hydrostatic pressure, or a pipe burst and the pool was emptied by its own pump and not noticed in a timely manner. Both of these scenerioes would have damaged any type of pool. The main reason a fiberglass pool will never pop is the the deck around the pool and the vacuum created by the backfill will not allow the pool to lift. Fiberglass has flexability and while it will attempt to float, it cannot because the deck and backfill will hold it in place. As the water pressure underneath the pool builds, it will push up on the pool until the floor can no longer hold together and the floor bursts releasing the hydrostatic pressure. A 2 inch hole in the bottom of the pool would have avoided this whole disaster. A concrete pool has no give and when it attempts to float, the pressure will build until the entire pool lifts and it will take everything connected to it. No pool should ever be drained except by a professional who understands and is equipped in addressing hydrostatic pressure. I have drained and resurfaced over 250 fiberglass pools and have to date not had a single pool damaged by hydrostatic pressure. We install a hydrostatic relief point in every pool we work on and our pools are installed in a manner to stabilize the ground around the pool perminantly. In many of the pools I have worked on a few extra steps would have prevented the damage that occured.