Gunite, vinyl or fiberglass: which pool for a Hamptons house?

The three, in one table

	Gunite	Vinyl liner	Fiberglass
Long Island cost, 2026	$90,000–140,000 standard; $100,000–400,000+ custom; $100–280/sq ft	$40,000–70,000; $45,000–100,000 complex (single source)	$45,000–85,000; $90,000–120,000+ with extras (single source)
Structure	30–50+ years (sources disagree on the low end)	15–20+ years	20–30 years
Finish or liner	Plaster about 10 years ($4/sq ft); quartz $5–10; pebble 20+ years ($10–20/sq ft)	Liner every 8–10 years on Long Island, $5,000–7,500, 28-mil spec	Gelcoat; no clean refinish-cycle figure found
Shape	Anything	Rectangles and gentle curves	Factory shapes and sizes
Build time	12–16 weeks typical; 4-week cure	Weeks	Days to weeks, plus the crane

Gunite

Concrete sprayed over a rebar cage in the shape of the hole. It is the reason Hamptons pools look the way they do: freeform, deep ends, a spa spilling into the shallow end, a sun shelf, an infinity edge on the ocean side. The shell is a 30–50+ year structure; what you maintain is the finish, and the finish is the cost of ownership nobody mentions at the sales meeting: plaster about every 10 years, pebble every 20 or more, $6,000–20,000 a time. A 20×40 gunite with a spa, pebble, automation, a cover and a heater is a $200,000 project on the South Fork before the pool house.

Vinyl

A steel or polymer wall panel structure with a vinyl liner over a sand or vermiculite floor. The cheapest to build and the cheapest to keep, with one recurring bill: a new liner every 8–10 years on Long Island, $5,000–7,500, 28-mil because of the freeze-thaw. Vinyl is soft underfoot and tolerant of a lot, but it is the pool that ends up with a puppy-claw tear in July, and it does not do spas or vanishing edges. Many of the 1970s–90s pools in Springs, Northwest Woods, Montauk and North Sea are vinyl and on their third or fourth liner.

Fiberglass

A one-piece shell built in a factory, trucked in and craned into a prepared hole. Fastest to install, smooth and non-porous (which helps chemistry), a 20–30 year shell, and limited to the shapes and sizes the factory makes and the truck can carry. The crane is the Hamptons problem: a village lot with a hedge, a narrow drive and neighbors on three sides is not a fiberglass site. We could not find a trustworthy source comparing fiberglass, vinyl and gunite on a high water table or in salt air, so we do not claim one; what we can say is that Sag Harbor's rule that a pool sit above the seasonal high groundwater table, proven by a test hole, applies to all three.

Which one

Gunite if the pool is part of the house's architecture, if you want a spa or a shape, and if the budget starts at six figures. Vinyl if the budget is the deciding factor and you accept a liner every decade. Fiberglass if speed matters, the shape on offer is the shape you want, and the crane can reach. On the South Fork the answer is gunite far more often than not, which is why the builders here are gunite builders.