Vinyl siding is made primarily of polyvinyl chloride, or PVC — a durable, chemically stable polymer built to handle decades of outdoor exposure.
Vinyl siding is made primarily of polyvinyl chloride, or PVC — a durable, chemically stable polymer built to handle decades of outdoor exposure.
Quality vinyl siding uses a co-extruded, two-layer construction: a PVC substrate base and a proprietary outer layer engineered to resist sun, rain, ice, and wind year after year. For homeowners evaluating the best siding for New England homes, understanding what’s in the product helps explain why it performs so well in harsh climates.
What Rockingham County Homeowners Should Know About Vinyl’s Composition
- PVC origin: PVC resin starts with two common building blocks: chlorine derived from salt and ethylene from natural gas. These are combined and optimized with other ingredients to create a weatherable, long-lasting exterior panel.
- Two-layer construction: Exterior Portfolio Vinyl Siding is manufactured using a co-extruded, permanently bonded two-layer system. The substrate layer is primarily PVC, while the outer layer is a proprietary blend designed to stand up to the elements.
- Water resistance: PVC is one of the most weatherable polymers available and is virtually impervious to water. That’s a meaningful advantage for homes in the Seacoast Region where moisture and coastal humidity are ongoing concerns.
- Fire behavior: Rigid PVC requires 45% oxygen to sustain combustion, which is higher than the 21% found in normal air. Fewer than 2% of all home fires originate from exterior wall surfaces, making vinyl a reasonably safe cladding choice.
- Energy efficient siding options: Insulated vinyl siding adds a foam backing that improves a home’s air tightness by an average of 11%. In studies of five re-siding projects, homeowners saw an average energy savings of 5.5% after installing insulated vinyl.
- Proven popularity: Vinyl siding has been the number one exterior cladding choice in the U.S. and Canada since 1995. Its average national cost is $18,000, with an 118% ROI at resale — making it one of the most accessible energy efficient siding options available for Southern NH homes.
| Vinyl Type | Composition | Key Benefit | Best For |
| Standard vinyl | PVC substrate + outer layer | Low maintenance, water resistance | Budget-conscious installs |
| Insulated (foam-back) | PVC + EPS foam backer | 11% air tightness improvement | Energy efficiency priority |
| Composite vinyl (Celect®) | Cellular PVC composite | Seamless look, impact resistance | Premium curb appeal |
Choosing the Right Vinyl for Your Home
Top Pick: Foam-backed insulated vinyl siding for homeowners who want the most energy-efficient siding option available — it delivers low maintenance, strong durability, and measurable energy savings in one product.
Good alternative: Standard vinyl siding for homeowners focused on budget and curb appeal, with an 118% ROI and virtually no ongoing maintenance costs.
Worth knowing: Not all vinyl is created equal — product thickness, layer construction, and warranty terms vary significantly between product lines. Ask your contractor about the specific product before committing.
Ready to upgrade your home’s exterior? Coastal Windows & Exteriors is the #1 woman-owned exterior remodeling contractor in New England, with 7,000+ installations across Massachusetts, New Hampshire, and Maine.
Request a free estimate by clicking here.
Learn more about James Hardie and vinyl siding by clicking here.
For more questions about siding FAQs click here.
Sources:
- Polymeric Exteriors Insulated Siding Guide — https://polymericexteriors.org/wp-content/uploads/2017/09/ISHI_Guide_Update_January_20141.pdf
- Exterior Portfolio Vinyl Sustainability Guide — https://RoyalBuildingProducts.com/ExteriorPortfolio
- Cost vs. Value Report 2024 — https://remodeling.hw.net/cost-vs-value/2024
- Fixr Home Siding Statistics — https://www.fixr.com/articles/home-siding-statistics
- Coastal Windows & Exteriors — https://mycoastalwindows.com
Last Updated: March 2026
