A buddy of mine and I are both trying to decide on pools at our respective houses. I'm trying to decide between getting a gunite pool or fiberglass. He's going with gunite. My issue is the soil in and around San Antonio - it's very expansive and shifts a lot depending on the moisture. Lots of people have foundation issues eventually because of the soil shift and I worry that the gunite pool may suffer the same fate and crack whereas a fiberglass pool may be more resistant to a little ground shift here and there, at least moreso than the concrete. On the other hand, a relative of mine in this area has fiberglass, but already had a crack due to an issue at install which allowed some water down the side of the fiberglass and compacted a portion of the sand allowing a gap under the pool which cracked due to the unsupported weight. Looking for input from people who have more experience and have the pools already...would you do it different if you had the chance or make the same decision on pool type?
Gunite vs fiberglass in expansive soil
- Thread starter TXchad
- Start date
- Jun 22, 2014
- 52,038
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Hello and welcome! 
Honestly, in our area, I'm not sure if either matters. At first I did which is why I got a FB. No doubt our soil shifts and settles each season. Always fixing fence posts and such. This black gumbo soil is not the best for stability that's for sure. I suspect in either product, it all boils down to base prep and how it was installed. Our installer, off of Hwy 281, did fine, however they used sand. This was before I came to TFP and knew better, otherwise I would've insisted in more of a crushed pebble/granite base. Our pool settled slightly after a couple years so it's slightly off level. Most visitors never even notice, it's just something we see as the owner. Otherwise no issues to date after 5 years.
I had a friend who's gunite did crack and required repair, but I have others who have yet to have an issue whether it be S.A., Converse, or La Vernia. So again I really think a lot depends on preparation. In either scenario, I would encourage soaker hoses just like around our homes to try and keep the soil consistent this time of year. That should help reduce the gaps around the pool decking and such.
Aside from that, each pool comes with pros & cons. We are pleased with our FB pool, but I did learn some things that in hindsight I wish I could do over (soil prep, chemically, etc). But it's easy to care for and a pool certainly makes the backyard a completely new living environment.
Honestly, in our area, I'm not sure if either matters. At first I did which is why I got a FB. No doubt our soil shifts and settles each season. Always fixing fence posts and such. This black gumbo soil is not the best for stability that's for sure. I suspect in either product, it all boils down to base prep and how it was installed. Our installer, off of Hwy 281, did fine, however they used sand. This was before I came to TFP and knew better, otherwise I would've insisted in more of a crushed pebble/granite base. Our pool settled slightly after a couple years so it's slightly off level. Most visitors never even notice, it's just something we see as the owner. Otherwise no issues to date after 5 years.I had a friend who's gunite did crack and required repair, but I have others who have yet to have an issue whether it be S.A., Converse, or La Vernia. So again I really think a lot depends on preparation. In either scenario, I would encourage soaker hoses just like around our homes to try and keep the soil consistent this time of year. That should help reduce the gaps around the pool decking and such.
Aside from that, each pool comes with pros & cons. We are pleased with our FB pool, but I did learn some things that in hindsight I wish I could do over (soil prep, chemically, etc). But it's easy to care for and a pool certainly makes the backyard a completely new living environment.