Islip's Climate Data and Its Top-Rated Window Pros
Islip sits in IECC climate zone 4A, which sets the energy-performance bar here no matter who ends up installing your windows. A window license file doesn't cover Islip on this site, so Google Maps supplies the 7 ranked names you see below. Checked September 2026.
Google Maps ratings checked · How we rank
4AIECC climate zone · ENERGY STAR North-Central zone
Islip's climate zone, in plain terms
New York-Newark-Jersey City, NY-NJ runs a January average near 32°F and climbs to about 75°F by July, a swing that adds up to roughly 5,148 heating degree days most winters, with 853 on the summer cooling side of the ledger.
That load is the actual argument for paying up for a better U-factor in Islip, separate from anything a brochure claims.
Zone 4A's requirement is the floor; Islip's specific load is what tells you whether beating that floor is worth the extra cost.
Data: U.S. EPA / DOE, ENERGY STAR, ENERGY STAR Version 7.0 Climate Zones by County/ZIP (Windows, Doors, and Skylights) (V7.0); Pacific Northwest National Laboratory (DOE Building America), Guide to Determining Climate Zone by County: Building America and IECC 2021 Updates (PNNL-33270) (2021 IECC), from the nearest NOAA station 6.6 mi away.
What FEMA's risk data says about Islip
FEMA scores Suffolk County's winter-weather risk as Very High and its flood risk as Relatively High.
Winter risk in Islip weighs on U-factor and condensation resistance; flood risk weighs more on sill height and drainage detailing than on the glass package.
Treat these as two separate conversations with a Islip contractor, not one.
- Hurricane
- Relatively High
- Strong wind
- Relatively High
- Winter weather
- Very High
Data: FEMA, National Risk Index for Natural Hazards - County-level table, v1.20 (v1.20, December 2025).
Guides to finish before Islip window bids come in
- How to Read an NFRC Window Label Four numbers on one sticker decide most of a window's real-world performance. Here's what each one means.
- ENERGY STAR Window Criteria by Climate Zone ENERGY STAR splits the country into four zones, each with its own numbers. Here they are, and why the Northern zone works backward from the other three.
- Impact Windows vs. Shutters in Florida's Hurricane Zones Florida gives homeowners two paths to a protected opening. Here's how each one is tested, and where the HVHZ raises the bar further.
Islip's top-rated window installers, by Google
The order below weighs a Google rating against its review count, the same way this site weighs a U-factor against a brochure claim: on the number, not the name. Treat it as a rating, never as proof of a license, bond or HVHZ approval.
- Prestige Window and Door Repair Long IslandGoogle reviews
- Champion GlassGoogle reviews
- Window NationGoogle reviews
- V&P Siding & Window CorpGoogle reviews
- Royal Windows and DoorsGoogle reviews
- EcoView Windows of Long IslandGoogle reviews
- Baradzi Glass IncGoogle reviews