Q&A: Painting a gunite pool and the risk of a pool pop-out

Question:

I have a house in Orlando and the pool needs painting. The only thing is I have been told that I cannot drain the pool as it will pop out of the ground.

Can you advise me please on how to paint it.

Answer:

Example of a Gunite Pool Pop Out

A fiberglass pool that popped out of the ground after sitting empty.

If you have to paint a gunite pool, you need to make sure that the pool does not get left open any longer than absolutely necessary. Hiring a pool company to do this for you is a great idea. The concern with emptying a gunite pool is that it is like a concrete boat, and if the water pressure holding the pool in the ground becomes less than the water (hydrostatic) pressure in the ground, the pool can pop out. (the expense to fix a pool pop out is almost the same if not more than installing it new)

The main drain in the bottom of the pool should have a hydrostatic relief valve. If the valve is working properly, when you drain the pool, if the water pressure is higher in the ground it will pop the valve and allow the water to enter the pool. Another measure that pool contractors take if the water table is a concern, would be to drill holes through the gunite of the pool in the deep end to allow for the water to pass through as well. This is more typically done when a gunite pool is getting new marcite or pebble, as the last step is to fill the holes back in as the pool starts to fill again with water.  The fastest way to get a pool filled back up is obviously by truck, and the second would be using multiple hoses (if you have city water). If you water has minerals/iron and you freshly paint a pool I’d try to get the cleanest water back in there as possible.

If you do paint the pool, be sure you have a plan and understand the timetable, how long the paint needs to dry, and what your risk factors for ground water are. Even if you hire a pool contractor to paint the pool they may have you sign a risk waiver (often required by their insurance company) stating that you know the risks of draining a pool.