We are building a new house and would like a pool but our builder is worried about pressure against the foundation wall with possibility of expansion of pool. Is this a real worry? Do a fiberglass pool expand much? If so, how much? The more information about this that you can give me would be appreciate. We were looking to put in a pool on a smaller lot so would be about 6 feet off the house. We were actually looking at a liner pool but are wondering if it would be better to do fiberglass. Any information would be extremely helpful!!