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Insurer has declined a claim on the pool due to the hydrostatic pressure.

Details of events:

    1.     Dec 21: Pool is emptied and checked by pool specialist for painting. Hydro valve is placed, no issues arise.

    2.     Dec 21 afternoon: Pool is empty, no signs of bubbling, hydro removed, pool gets prepared for painting, but specialist advises that a storm is on the way so they will do the painting another day. No indication of bubbling or damage to pool.

    3.     Dec 22: Storm passes through and that afternoon client notes the pool starting to bubble, specialist fills the pool to stop further bubbling.

Insurers have advised they will decline due to the hydrostatic clause.

It seems a little presumptuous to think it was caused by hydrostatic pressure rather than hydrodynamic pressure?

Thoughts or suggestions are appreciated.

Crossley Gates Replies:

This sounds like a proximate cause issue.

As I understand it, the hydrostatic pressure exclusion relates primarily to fibreglass pools and excludes the risk of the pool popping out of the ground when it lies empty. This occurs because of the pressure of the water in the soil surrounding the fibreglass wall well exceeding the air pressure on the other side (because the pool is empty) and the differential lifts the fibreglass structure out of the ground.

This is a well-known risk and because of this underwriters won't insure it as they expect the owner to take measures to prevent it happening. One of those measures is the hydro valve you refer to.

I am unsure from your post above about the exact sequence of events, but it appears the valve was removed in preparation for painting but this did not proceed on the day in question as rain was forecast. The valve was not reinstalled. The rain fell and the pool lifted.

The rain would have increased the hydrostatic pressure.

If reinstalling the valve would have alleviated this increase and stopped the lifting, I believe the proximate cause was the failure to reinstall the valve in the certain knowledge of rain, leading to the inevitable hydrostatic pressure issue that damaged the pool. In this case, the exclusion may well apply.

June 2024

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