Cornerstone Building Brands — Complete Window, Door & Siding Systems

All window lines are NFRC rated for U-Factor, SHGC, and Visible Transmittance. ENERGY STAR qualified products are available across all climate zones. Request our current NFRC-certified performance data sheet for any specific line.

Yes. We maintain Miami-Dade NOA listings and Florida Product Approvals on our impact-rated window and door lines. Our technical team provides NOA numbers and supporting documentation for code submissions.

Yes. Environmental Product Declarations are published for our core window and door product lines. They satisfy MR Credit requirements under LEED v4 and v4.1. Contact our technical team to request the relevant EPD documents.

Vinyl window and door lines carry a limited lifetime warranty for the original purchaser covering frame and sash construction. Glass seal failure is covered for 20 years; hardware for 10 years. See our Warranty page for full details.

Locate your model number on the unit label, then visit our Warranty page or call 1-800-555-0190, option 2. Claims are reviewed within 5 business days of receipt.

Yes, with modified terms. Most product lines transfer to subsequent homeowners at reduced coverage. Vinyl siding transfers at 50% coverage after the first transfer. Contact us to confirm terms for your specific product line.

Vinyl (our primary offering): Lower upfront cost, no painting required, U-Factor as low as 0.17 with triple-pane glass packages, and broad color stability under typical UV exposure. Vinyl's coefficient of thermal expansion is higher than fiberglass — in extreme temperature swings (below −20°F or above 120°F surface temperature), frame flex can marginally affect air infiltration ratings over time. Best suited for production residential, multifamily, and renovation where cost predictability matters.
Fiberglass: Higher dimensional stability across temperature extremes, closer expansion coefficient to glass (reducing seal stress), and paintable surface. Upfront cost is typically 20–40% higher per opening, and lead times for custom sizes are longer. Better suited for custom high-end residential where performance at temperature extremes or premium aesthetics justify the cost premium.
Our recommendation: For most climate zones and construction segments, vinyl delivers better value. For projects in extreme northern climates or specifications requiring painted surfaces with long refinishing cycles, we will say plainly that fiberglass deserves a side-by-side specification review.

Vinyl siding (our product): No field painting ever required, moisture-immune core, and lowest installed cost per square foot among primary cladding options ($3–$8/sq ft installed depending on profile and region). Vinyl does not accept field paint once installed, limiting future color-change options to re-siding. Impact resistance is lower than fiber cement — hail events above 1.75-inch diameter can dent or crack vinyl panels in direct hits.
Fiber cement (e.g., HardiePlank): Paintable surface allows color changes, higher impact resistance, and Class A fire rating without additional treatment. Installed cost is typically $6–$14/sq ft. Requires repainting every 8–15 years, adding long-term maintenance cost that narrows the lifecycle cost gap with vinyl.
Trade-off summary: Vinyl wins on first cost and maintenance simplicity. Fiber cement wins on impact resistance, fire rating flexibility, and paint customization. Both are valid choices — the right answer depends on project budget, HOA requirements, and regional weather exposure.