F-Series

Fiberglass windows & doors

Pultruded fiberglass has the thermal expansion of glass, the stiffness of a structural frame, and none of the maintenance of wood. The F-Series pairs GR85 and GR70 fiberglass profiles with our hybrid vacuum glass to reach whole-window performance that aluminum and vinyl cannot.

The line is built on two profile systems, F85 (85 mm) and F70 (70 mm), each offered in five window types: outswing casement with integrated screen, outswing casement, dual action, and two fixed variants. Doors complete the range. Every unit is made to order and delivered to site or to the modular factory.

NFRC certification of the F-Series is in progress (CSA Group physical testing of F85 and F70 fixed and tilt-turn units). Until labels are issued, published U-factors are simulation values from LBNL WINDOW and should be treated as design assumptions.

F85 fiberglass frame section with hybrid vacuum IGU

Window and door types

Fixed window

F85 Fixed

GR85 pultruded fiberglass frame, 85 mm depth, hybrid vacuum IGU. Two fixed variants (profile flipped) for sightline matching.

Frame	GR85 pultruded fiberglass (F85); GR70 (F70). Same head, jamb and sill profile around the whole unit for fixed, tilt-turn and outswing casement.
Glazing pocket	F85: 42 mm (6/12/6/12/6 triple or hybrid VIG stack 6 + 18 Ar + 6 + 0.3 V + 6; also 5 + 18 Ar + 5 + 0.3 V + 5).
Spacer	Kodispace 4SG thermoplastic spacer in the argon cavity; welded one-piece titanium-alloy edge seal on the vacuum unit.
Glazing bead	Aluminum, 2 mm wall.
Hardware	German multi-point locking; concealed hinge options.
Performance	Whole-window values by NFRC 100/200 simulation and physical testing (CSA Group); certification in progress. Tested claim basis: ZERO 08 configuration.

Dual-action inswing

F85 Tilt-Turn

Tilt for ventilation, turn for cleaning and egress. German multi-point hardware, concealed options.

Frame	GR85 pultruded fiberglass (F85); GR70 (F70). Same head, jamb and sill profile around the whole unit for fixed, tilt-turn and outswing casement.
Glazing pocket	F85: 42 mm (6/12/6/12/6 triple or hybrid VIG stack 6 + 18 Ar + 6 + 0.3 V + 6; also 5 + 18 Ar + 5 + 0.3 V + 5).
Spacer	Kodispace 4SG thermoplastic spacer in the argon cavity; welded one-piece titanium-alloy edge seal on the vacuum unit.
Glazing bead	Aluminum, 2 mm wall.
Hardware	German multi-point locking; concealed hinge options.
Performance	Whole-window values by NFRC 100/200 simulation and physical testing (CSA Group); certification in progress. Tested claim basis: ZERO 08 configuration.

Casement

F85 Outswing Casement

Outswing casement with the same head, jamb and sill profile as the fixed and tilt-turn units.

Frame	GR85 pultruded fiberglass (F85); GR70 (F70). Same head, jamb and sill profile around the whole unit for fixed, tilt-turn and outswing casement.
Glazing pocket	F85: 42 mm (6/12/6/12/6 triple or hybrid VIG stack 6 + 18 Ar + 6 + 0.3 V + 6; also 5 + 18 Ar + 5 + 0.3 V + 5).
Spacer	Kodispace 4SG thermoplastic spacer in the argon cavity; welded one-piece titanium-alloy edge seal on the vacuum unit.
Glazing bead	Aluminum, 2 mm wall.
Hardware	German multi-point locking; concealed hinge options.
Performance	Whole-window values by NFRC 100/200 simulation and physical testing (CSA Group); certification in progress. Tested claim basis: ZERO 08 configuration.

F85 Outswing Casement frame section, view 1

F85 Outswing Casement frame section, view 2

F85 Outswing Casement frame section, view 3

F85 Outswing Casement frame section, view 4

Casement with screen

F85 Casement + Integrated Screen

Outswing casement with an integrated insect screen in the frame.

Frame	GR85 pultruded fiberglass (F85); GR70 (F70). Same head, jamb and sill profile around the whole unit for fixed, tilt-turn and outswing casement.
Glazing pocket	F85: 42 mm (6/12/6/12/6 triple or hybrid VIG stack 6 + 18 Ar + 6 + 0.3 V + 6; also 5 + 18 Ar + 5 + 0.3 V + 5).
Spacer	Kodispace 4SG thermoplastic spacer in the argon cavity; welded one-piece titanium-alloy edge seal on the vacuum unit.
Glazing bead	Aluminum, 2 mm wall.
Hardware	German multi-point locking; concealed hinge options.
Performance	Whole-window values by NFRC 100/200 simulation and physical testing (CSA Group); certification in progress. Tested claim basis: ZERO 08 configuration.

F85 Casement + Integrated Screen frame section, view 1

F85 Casement + Integrated Screen frame section, view 2

F85 Casement + Integrated Screen frame section, view 3

F85 Casement + Integrated Screen frame section, view 4

Tilt / turn

F85 Dual Action

Dual-action window for rooms that need both trickle ventilation and a full opening.

Frame	GR85 pultruded fiberglass (F85); GR70 (F70). Same head, jamb and sill profile around the whole unit for fixed, tilt-turn and outswing casement.
Glazing pocket	F85: 42 mm (6/12/6/12/6 triple or hybrid VIG stack 6 + 18 Ar + 6 + 0.3 V + 6; also 5 + 18 Ar + 5 + 0.3 V + 5).
Spacer	Kodispace 4SG thermoplastic spacer in the argon cavity; welded one-piece titanium-alloy edge seal on the vacuum unit.
Glazing bead	Aluminum, 2 mm wall.
Hardware	German multi-point locking; concealed hinge options.
Performance	Whole-window values by NFRC 100/200 simulation and physical testing (CSA Group); certification in progress. Tested claim basis: ZERO 08 configuration.

Terrace door

F Outswing Door

Full-height fiberglass door on the GR85 profile system; inswing and outswing configurations.

Frame	GR85 pultruded fiberglass (F85); GR70 (F70). Same head, jamb and sill profile around the whole unit for fixed, tilt-turn and outswing casement.
Glazing pocket	F85: 42 mm (6/12/6/12/6 triple or hybrid VIG stack 6 + 18 Ar + 6 + 0.3 V + 6; also 5 + 18 Ar + 5 + 0.3 V + 5).
Spacer	Kodispace 4SG thermoplastic spacer in the argon cavity; welded one-piece titanium-alloy edge seal on the vacuum unit.
Glazing bead	Aluminum, 2 mm wall.
Hardware	German multi-point locking; concealed hinge options.
Performance	Whole-window values by NFRC 100/200 simulation and physical testing (CSA Group); certification in progress. Tested claim basis: ZERO 08 configuration.

Why fiberglass

Pultruded fiberglass profiles are made from glass fibers drawn through a resin bath and cured into a continuous, dimensionally stable section. The material expands and contracts at almost the same rate as the glass it holds, so seals stay tight through decades of freeze–thaw cycles. It does not rot, corrode or creep, and it can be painted in any color.

Conductivity is a fraction of aluminum's, which is why a fiberglass frame does not need a thermal break to outperform a thermally broken aluminum one. Combined with vacuum glass, the frame stops being the weak link of the envelope.

GlasFëns frames are produced by G-Ren on fiberglass-reinforced polyurethane pultrusions with an independent ASTM C518 conductivity test on record. Hardware and components come from established European suppliers; glass is produced by LandGlass (LandVac) with Jinjing and TGI coatings.

Frame materials compared →