A window company started by an architect.

GlasFëns Window Systems USA is a supplier of high-performance windows, doors and façade systems for buildings across North and South America. Our focus is fiberglass, with thermally broken aluminum for hurricane and high-wind applications, all based on proven European systems and fitted with German hardware. We exist to do one thing exceptionally well: deliver energy-efficient fenestration that performs at the highest level, approaching zero.

GlasFens, LLC is a Massachusetts company founded and led by Todd Fix, a licensed architect with more than thirty years in practice and a decade of work with fenestration manufacturers in Europe and Asia. The GlasFëns name dates to 2018, when the first fiberglass window quote went out to a Boston architecture studio; the company was re-established in 2026 around the F-Series fiberglass line and the hybrid vacuum-glass package.

We build lasting relationships with developers, architects, contractors and glazing contractors by pairing our products with real industry knowledge and hands-on support. We are not just a supplier; we are a partner through specification, value engineering and delivery, helping projects hit their performance targets without surprises along the way.

Our systems serve every sector, from single-family and multifamily residential to commercial, hospitality, prefab and Passivhaus-certified construction. Each one is engineered to order and built to the most demanding standards of thermal performance, security, acoustics and design. Our flagship fiberglass and vacuum-glass system reaches a whole-window U-value of 0.045 (R-22), with vacuum-glass IGUs standard across the range.

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