01/03 Windows & Doors
High-performance casement system
GC77 is the catalogue's high-performance casement window: a 77 mm frame with multi-chamber polyamide thermal breaks, offered in standard and hidden-vent versions and paired with an unusually wide range of opening hardware.
- Frame depth
- Thermal break
- Versions
- Glazing
GC77 profileSheet 4
(01)Features
What it does well.
01
Thermal-break construction
Multi-chamber polyamide strips separate the inner and outer aluminum, slowing the transfer of heat and cold through the frame — important for Canadian winters.
02
Standard or hidden vent
Choose a visible sash or a hidden-vent version where the opening sash sits behind the outer frame for a quieter, more uniform elevation.
03
Many ways to open
The catalogue lists side-hung, tilt-and-turn, tilt-and-slide, bi-folding, top-hung, bottom-hung, outward-opening and horizontal/vertical pivot hardware. Availability depends on configuration.
04
Double or triple glazing
Glazing is selected per project, balancing daylight, comfort and the performance a building requires.
Documented options
- Side-hung
- Tilt & turn
- Tilt & slide
- Bi-folding
- Top-hung
- Bottom-hung
- Outward opening
- Horizontal / vertical pivot
(02)Thermal-break construction
Take the frame apart.
Loading 3D section…
Fig. — Illustrative section
Illustrative model to explain how a thermally broken frame is built — not the exact geometry of any Winhoff profile. The thermal view is a concept sketch, not test or simulation data.
(03)Technical details
By the catalogue.
Only values printed in the supplied 2026 catalogue (PDF sheet 4). Thermal values are pending confirmation and are not shown.
| Frame depth | 77 mm |
|---|---|
| Thermal break | Multi-chamber polyamides |
| Versions | Standard and hidden vent |
| Glazing | Double or triple glazing options |
Catalogue-reported performance
Catalogue-reported test data for the tested configuration (test size 1000 × 2100 mm). Not a guarantee for all sizes or configurations.
- Design pressure
- Water penetration test pressure
- Air infiltration / exfiltration
- Class
- Test report
- Test size
Sections & configurations · 2
(04)Gallery
GC77 in place.
4 images
Architectural photographs are catalogue application imagery, not identified completed projects.
(05)Resources
Take it with you.
- Winhoff 2026 CataloguePDF · 4.4 MB · GC77 on sheet 4
- GC77 section — standard versionJPG reference · 480 × 344 px
- GC77 section — hidden-vent versionJPG reference · 480 × 332 px
- CAD, BIM or full test reports aren't published here. Request technical information for GC77
(06)Related systems
(✦) — Discuss your project
