New pool construction in the Hamptons: gunite, vinyl, fiberglass, and what a South Fork pool really costs

What it costs on Long Island (2026)

Pool	Cost
Gunite, standard build	$90,000–140,000; $100–280 per sq ft
Gunite by size	14×28 from $90,000 · 16×32 $105,000–130,000 · 20×40 often above $140,000; shell alone (16×32) $55,000–80,000
Gunite, custom	$100,000–400,000+; a Hampton Bays builder puts most of its projects at $100,000–150,000 within a $75,000–200,000+ range
Vinyl liner	$40,000–70,000 typical; $45,000–100,000 on complex sites (single Long Island source)
Fiberglass	$45,000–85,000 standard; $90,000–120,000+ with extras (single Long Island source)

What moves a gunite number: a spa or waterfall +$8,000–35,000; a pebble finish +$4,000–8,000; automation +$3,000–8,000; travertine coping $28–55 per linear foot (bluestone $25–50); filtration $4,000–8,000; permits $800–2,000; rock or boulder excavation +$3,000–15,000 on the moraine; a limited-access lot +15–30%; an automatic cover $15,000–25,000; a gas heater $3,300–6,800 installed or a heat pump $2,500–7,500. A 20×40 gunite pool with a spa, pebble finish, automation, cover and heater is a $200,000 project before the pool house, the fence and the landscaping, which is why the Hamptons figures run past the national ones.

Gunite, vinyl or fiberglass

Gunite is a concrete shell sprayed in place: any shape, any depth, a spa in the same shell, a 30–50+ year structure, and a finish that needs redoing every decade or two (plaster about 10 years, pebble 20+). It is what the South Fork builds. Vinyl is a steel or polymer wall with a liner: the cheapest to build, a liner every 8–10 years on Long Island at $5,000–7,500, a structure that runs 15–20+ years. Fiberglass is a factory shell craned into the hole: fastest to install, 20–30 year shell, limited shapes and sizes, and a crane on a tight village lot is its own project. We have not found a trustworthy source comparing the three on a high water table or in salt air, so we do not claim one.

The calendar

Design to swim is 12–16 weeks for a typical gunite pool and up to 5–6 months for a complicated one: permitting 2–4 weeks in an ordinary jurisdiction, construction 8–12 weeks, and a 4-week gunite cure that nobody can shorten. Long Island builders say to book 4–6 months ahead for a spring completion. Two Hamptons realities stretch that: the Town of East Hampton's building department reported a 16–20 week permit backlog in 2026 against a 15-day statutory clock, and the 2020–2022 pool boom, when Bloomberg reported Hamptons owners waiting until 2023 for a dip, showed how fast the season fills. A pool for next summer is designed this fall.

The rules that shape the plan

• Barrier and alarm. New York requires a barrier at least 48 inches high around the pool with no openings over 4 inches and self-closing, self-latching gates, and every pool built or substantially modified since December 14, 2006 must have an approved pool alarm; where a house wall forms part of the barrier, doors need alarms. A pool with an automatic safety cover is exempt from the alarm requirement.
• Electrical. GFCI protection on every pool circuit and equipotential bonding of the pool's metal parts under NEC Article 680, by a licensed electrician.
• Town of East Hampton. Side and rear setbacks are doubled for pools, decks and pool equipment; no structure, pools included, within 150 feet of a wetland; a pool house is capped at 200 square feet plus 400 square feet of open porch, one per lot, and it is the only accessory building allowed plumbing besides an approved ADU; noise 65 dBA by day and 50 at night at the property line.
• Village of East Hampton. Its own code doubles the accessory-structure setback for pools, pool equipment and pool houses, expressly for noise.
• Town of Southampton. Pool equipment at least 10 feet from every property line (8 in R-10 districts) with screening; structures 150 feet from wetlands; a drywell for backwash; lot coverage capped, with up to 2% over at the Chief Building Inspector's discretion.
• Village of Sag Harbor. A 15-foot pool setback; the pool must sit above the seasonal high groundwater table, proven by a test hole; cartridge filtration only, so nothing backwashes to the ground; equipment in a closed, noise-screened enclosure.
• Village of Southampton. Pools in the rear or side yard only, behind the 4-foot barrier.
• Suffolk County. Pool builders, service and maintenance contractors need a special pool endorsement on the county Home Improvement Contractor license, with industry certification and two years' experience for anyone touching pool plumbing, heating or electrical unless already a licensed plumber or electrician. A pool is set back 20 feet from a septic system under the county sanitary code, per one reported ruling.

Water, ground and salt

Filling a 20×40 pool takes roughly 33,000–39,000 gallons: about $87 in Suffolk County Water Authority water charges at 2026 rates, which surprises people who expected worse. A private well can fill it too, but iron and manganese in well water stain the new finish the moment chlorine goes in; test first or filter the fill. The ground matters more than the water: on the outwash plain the sand drains and the lower layers sit wet in spring; on the moraine there are boulders; near the bays and ponds the water table is a few feet down and a shell built without a hydrostatic relief valve can float. Near the ocean, specify cupro-nickel heat exchangers and corrosion-resistant hardware from the start.

Insurance

A pool raises liability. The industry guidance is to carry at least $300,000–500,000 of liability coverage instead of a typical $100,000 base, and an umbrella policy on top; tell the carrier before the water goes in.