FG65 is a slim-profile passive-grade window system combining fire-rated GFRPU construction with triple glazing options including vacuum glass — achieving U-values as low as 0.9 W/(m²·K). Designed for inward-opening applications, the FG65 supports both tilt-and-turn and casement configurations in single and double sash, making it the ideal choice for passive house retrofits and new-build low-energy projects.
GFRPU window profiles · 65 mm system · passive ultra-low energy fire-rated series
Glass Fiber Reinforced Polyurethane (GFRPU) window system · 65 mm frame · triple & vacuum glazing · U-value down to 0.9 W/(m²·K)
The FG65 is a slim-profile passive-grade window system combining fire-rated GFRPU construction with triple glazing options including vacuum glass — achieving U-values as low as 0.9 W/(m²·K). Designed for inward-opening applications, the FG65 supports both tilt-and-turn and casement configurations in single and double sash, making it the ideal choice for passive house retrofits and new-build low-energy projects.
Thermal conductivity
0.34 W/(m·K)
vs. aluminum 160 W/(m·K)
Flexural strength
≥ 1,200 MPa
~5× aluminum · vs. PVC 30 MPa
Flexural modulus
41.3 GPa
vs. PVC 2.2–5 GPa
Density
2.1 g/cm³
25% lighter than aluminum (2.79)
Thermal expansion
0.5–0.8 × 10⁻⁵ /K
vs. aluminum 2.2–2.4 × 10⁻⁵/K
Dimensional shrinkage
≤ 0.2%
ΔT 40°C deformation only 0.15 mm
Glass fiber content
70–82%
PU + additives 18–30%
Carbon footprint
1/8 of aluminum
Manufacturing process emissions
Performance advantages
Thermal conductivity 470× lower than aluminum · flexural strength ~5× aluminum · failure temperature >1,100°C vs. aluminum ~680°C · forms carbonized fire curtain · sound insulation ≥ 40 dB · dimensional shrinkage ≤ 0.2% · stable from −40°C to +80°C
Engineering & fabrication advantages
Pultrusion process · straightness ≤ 0.25 mm/m · Euro-groove hardware compatible · CNC-machinable · coating adhesion ≥ Grade 1 · weathering life ~1.5× aluminum powder-coat · corrosion-resistant for coastal environments · LEED / BREEAM / Passivhaus compatible
| Property | Aluminum | GFRPU (this product) | Nylon thermal break | PVC | Polyester FRP |
|---|---|---|---|---|---|
| Density, g/cm³ | 2.79 | 2.1 | 1.3 | 1.5 | 1.9 |
| Thermal conductivity, W/(m·K) | 160 | 0.34 | 0.30 | 0.35 | 0.45 |
| Flexural strength, MPa | 250 | ≥ 1,200 | 80–180 | 30 | 300–400 |
| Flexural modulus, GPa | 50–80 | 41.3 | 2–5 | 2.2–5 | 10–22 |
| Dimensional shrinkage, % | 0.6 | ≤ 0.2 | 0.4 | 0.4 | 2 |
| Linear expansion, 10⁻⁵ K⁻¹ | 2.2–2.4 | 0.5–0.8 | 2.4–3.5 | 5–8.5 | 0.73 |
Orange column = GFRPU (this product). All values from material comparison testing. GFRPU leads in thermal conductivity, flexural strength, and dimensional stability.
> 1,100°C
Failure temperature
vs. aluminum ~680°C melting point. Furnace temperature exceeds 800°C within 10 min of fire testing.
Carbon curtain
Carbonizes on combustion
Thermoset matrix + >70% glass fiber forms a stable carbonized layer — structurally blocks flame spread.
0.5 – 1.5 h
Fire integrity (EI 30 / EI 60)
Meets fire-resistance requirements while simultaneously satisfying energy-efficiency targets.
280°C
ccPVC fails at just 280°C
GFRPU's inorganic glass fiber matrix provides structurally superior fire behavior at every stage.
Series: FG65 · Window · 65 mm frame depth | Window types: Inward tilt & turn (single & double sash) · Inward casement (single & double sash)
Fixed performance — all glazing configurations
Wind load
Grade 9
GB/T 7106
Watertightness
Grade 6
GB/T 7106
Airtightness
Grade 8
Highest class
Sound insulation
≥ 40 dB
Grade 4 · GB/T 8485
Best U-value
0.9
W/(m²·K)
Glazing configurations & thermal performance
Glazing
5 Low-E + 9Ar + 5 + 9Ar + 5
U-value W/(m²·K)
1.6
Wind
9
Water
6
Air
8
Glazing
5 Low-E + 9Ar + 5 Low-E + 9Ar + 5
U-value W/(m²·K)
1.5
Wind
9
Water
6
Air
8
Glazing
5 Low-E + 9Ar + 5 Low-E + 9Ar + 5 · warm edge
U-value W/(m²·K)
1.3
Wind
9
Water
6
Air
8
Glazing
5 Low-E + 16Ar (WE) + 5 Low-E + 0.3V + 5C · vacuum glass
U-value W/(m²·K)
0.9
Wind
9
Water
6
Air
8
Lower U-value = better insulation. Wind (Grade 9), watertightness (Grade 6), airtightness (Grade 8), and sound (Grade 4) are consistent across all four configurations. Config D incorporates vacuum glazing for maximum thermal performance.
Custom project enquiry
Have a specific project in mind?
Tell us your opening dimensions, performance requirements, and glazing preferences — our technical team will recommend the right series and configuration for your project.
| Test item | Industry reference | Our standard |
|---|---|---|
| Straightness per 1 m | 0.40 mm | ≤ 0.25 mm |
| Straightness per 3 m | 3 mm | ≤ 2 mm |
| Perpendicularity | 0.6% | ≤ 0.4% |
| Wall thickness tolerance | ± 0.2 mm | ± 0.2 mm |
Straightness and perpendicularity tolerances match the high-precision grade of aluminum extrusion — a recognized industry benchmark for window profile fabrication accuracy.
Multiple finish options
Gloss, matte, and textured surfaces via proprietary coating. Consistent color, no pinholes or cracks.
Coating adhesion
≥ Grade 1
Color shift E ≤ 5 after ≥ 6,000 h accelerated weathering.
Weathering lifespan
1.5× aluminum powder-coat
Coating durability approximately 1.5× that of standard aluminum alloy powder-spray finish.
Coastal corrosion resistant
Suited for high-salinity coastal environments where aluminum or steel corrodes prematurely.
Fire-rated performance
GFRPU frame meets EI 30 / EI 60 requirements for ultra-low energy, fire-rated building envelopes.
U-value down to 1.3 W/(m²·K)
Dual Low-E triple glazing meets passive house and NZEB thermal envelope targets.
Grade 8 airtightness
Highest GB/T 7106 class — minimizes infiltration losses and supports low-energy HVAC sizing.
Sound insulation ≥ 40 dB
Suited for urban, transit-adjacent, and institutional projects.
3 opening configurations
Casement, top-hung, and combination — all within the same 60 mm GFRPU frame system.
Euro-groove hardware compatible
Works with standard European hardware — no proprietary fittings required.
FG65 Window Series — Technical Data Sheet
Full performance specs · GFRPU window profile cross-section drawings · installation guidelines
Test Reports & Certifications
GB/T 7106 · fire-rating documentation · Intertek sound test report · available upon request
Standards: GB/T 7106 (wind load, watertightness, airtightness) · GB/T 8485 (sound insulation) · EN-standard test reports available upon request.
