I'm starting a multi-phase remodel of my existing IG gunite pool. Installation of remodel pavers and coping over the existing concrete deck is scheduled to start in two weeks. The marcite pool will be resurfaced with a Pebble-Tec finish later on. I'm also updating the 1993 installed Fiberstars fiber optic lights with a Fiberstars PAL Treo LED retrofit system in order to utilize the existing 1-1/2 inch conduit and niches. I am also replacing all of the original Caretaker 99 pop-up heads (20 total). Some of the heads are broken internally and cannot be removed with the head removal tool on a pole...I will need to work on getting them out of their collars once I drain the pool.
My question is a simple one: How long can a gunite pool be drained without damaging the plaster? I would like to keep the pool dry and out of service for a month or longer while I renovate everything using different contractors for the pavers, screen enclosure upgrades, and pool resurfacing. I had the pool resurfaced in 2001 when I purchased the home (mediocre job done by the contractor I hired back then). The pool does have a hydrostatic valve that I plan to remove and replace with a new one. I've read several articles that marcite will dry out and may de-laminate from its substrate if left drained for too long. My question is really this...how long is too long?
I'm not too concerned about the pool floating out since the property sits on an elevation, the soil is sandy and I've never had any standing water issues (an it sometimes rains 5" or more in a day here in Florida.) The water table should not be too high in my vicinity and I will remove the hydrostatic plug when I drain the pool.
I'd appreciate some feedback on how long I can safely leave my pool emptied given that the existing layer of marcite will need to be removed during the prep work for the pebble finish installation.