This is from Aqua Pros’ perspective, which includes installing vinyl liner pools since 1985 and fiberglass pools since 1999. For this comparison I am speaking from my personal experience and I have always demanded the highest quality of both types of pools.

Getting Started: A fiberglass pool is delivered as a one piece shell. The shell is crane set into a pre-prepared hole on a bed of stone. Its critical the excavation is carefully done so as not to require an excessive amount of stone. In addition, the finished stone bed must be solid and meet the manufacturers specifications so the pool sets level and no settlement of the base material occurs.
Our vinyl liner pools are delivered as panels of specially coated, galvanized steel. We carefully excavate and shape the hole for the pool so the panels sit level and conform to the shape of the pool and its liner.

Shape and Size: Fiberglass pools are limited to shapes offered by the manufacturers, and also limited in size because they’re delivered by truck and trailer to the job. Due to Department of Transportation regulations, Fiberglass pools must be DOT permitted and do not exceed 16’wide x 40’-44’ in length.
Vinyl liner pools can be custom built onsite to most any shape and size. I tell our vinyl lined pool clients, if they can draw it, I can build it.

Installation Time: We’ve found no real difference from start to finish in fiberglass and vinyl liner pools. Our crew can complete either pool in a 10 day to 2 week window.

Upfront Cost: Fiberglass pools are more costly than vinyl liner pools on the front end. However, if one starts adding features such as benches or ledges to a vinyl lined pool of the same size, the costs can soon become very close to equal. There is also the consideration of replacing the liner down the road 10 years.

Maintenance and Chemicals: A quality Fiberglass pool’s interior finish should have an indefinite life if installed correctly and maintained well. A well installed, well maintained vinyl liner should have at least a 10 year lifespan. Since both interior finishes are mostly not porous, there’s very little difference in the chemical cost of maintaining either pool. One does need to be very careful about chlorine levels in vinyl liner pools, however overly high levels of chlorine in a fiberglass pool is wasteful and will lead to premature fading of the gelcoat finish.

General: Vinyl liners can be cut but they can also be patched. I once put 12 patches on a new liner after the customer’s dog got in and struggled to get out. We say that a patch is as good as new vinyl and can be done with material that matches. There are differences in how liners are made and we demand the highest quality vinyl and also order our liners as Precision Fit. Our steel pool walls have the maximum amount of strength and corrosion resistance built into them to ensure our clients get maximum life from their pool investment. I installed my first fiberglass pool in 1999 and we’ve never had to repair or replace its interior finish.