Verified from the manufacturer’s own documentation · last checked September 19, 2026
| Manufacturer | Marvin |
|---|---|
| Series | Essential |
| Frame material | Ultrex fiberglass inside and out. Marvin states Ultrex is 8 times stronger than vinyl and 3 times stronger than wood-vinyl composites, has a low thermal expansion rate, is heat resistant and non-corrosive, and expands at virtually the same rate as glass. Marvin states Ultrex contains no sawdust or vinyl |
| Styles / configurations | Double-hung, casement, awning, glider, picture and direct glaze, plus specialty shapes including round top, trapezoid, triangle, pentagon and octagon; patio doors are offered in the same collection. Custom sizes available in 1/64 inch increments |
| Glass options | Dual-pane and triple-pane options; grilles between the glass in several styles; ENERGY STAR certified glass options offered |
| U-factor | Not published by Marvin as a single range. Performance data is published per product in Marvin's product resources. Configuration dependent: check the NFRC label on your quote |
| SHGC | Not published by Marvin as a single range. Configuration dependent |
| VT | Not publicly specified |
| ENERGY STAR | Marvin states Essential is available with ENERGY STAR certified glass options; certification follows the glass package and the climate zone |
| NFRC certification | Performance data, manuals and specifications are published per product in Marvin's Essential product resources |
| Warranty | Marvin Limited Warranty (effective January 12, 2026), fully transferable to later owners of the structure. Insulating-glass seal: 20 years up to 60 sq ft, 10 years at 60 sq ft and larger. Non-tempered glass stress cracks: 10 years. Hardware and other non-glass components: 10 years. Standard exterior fiberglass (Ultrex) cladding finish: 10 years (AAMA 625). Factory interior coated composite finish: 10 years. Labor is not covered: removal, installation, finishing, refinishing and disposal costs are excluded. Claims within 60 days of the defect appearing. Not a lifetime warranty (Infinity by Marvin is a separate brand with its own terms) |
| Positioning | Marvin's streamlined, budget-focused fiberglass collection, positioned below Elevate (wood interior, fiberglass exterior) and Signature. Marvin states that Ultrex has 8 times the tensile strength of vinyl and 3 times that of wood-vinyl composites, that it expands at virtually the same rate as glass, and that its acrylic finish is verified to AAMA 624 and about three times thicker than competing painted finishes. These are Marvin's own claims, not UpgradeWorth test results |
| Price position | Not publicly specified |
| Installation | Replacement, remodeling and new construction, sold through Marvin dealers |
Notes
Ultrex fiberglass inside and out. Re-verified September 19, 2026 against Marvin's January 2026 warranty and materials pages. Correction: the record gave Essential's exterior finish the 20-year AAMA 2605 term, which applies to aluminum cladding; Essential's Ultrex fiberglass cladding finish is covered 10 years. Warranty link updated to the current PDF; 60-day claim window added. Ultrex strength comparisons are Marvin claims. Performance data is style- and glazing-specific — check the NFRC label
Sources
Marvin Window and Door Limited Warranty (official PDF, marvin.com) for all warranty terms; Marvin Essential collection page and the Essential double-hung, casement, direct glaze and specialty shape product pages; Marvin Ultrex explainer page for the material claims; dealer pages for colour counts only