Timber inside
Choose timber species and finish to suit your rooms.
BO Fenster · Biel/Bienne
Timber-aluminium windows
Timber inside, aluminium on the facade.
Coordinate both sides
Aluminium outside
Coordinate the external cladding colour with the façade and connections.
Total installation depth
Compare the three DUOLINE profiles including cladding and available installation space.
Compare systems
DUOLINE combines a 68, 78 or 88 mm timber frame with 14 mm exterior aluminium cladding. Choose the glazing and finishes to suit your project.
3 / 3 systems
Timber-aluminium windows
DUOLINE 68
Timber-aluminium
- Profile depth
- 68 mm
- Glazing thickness
- 24–44 mm
- Seals
- 4
Figures depend on configuration. Conditions on the detail page.
Explore this system
Timber-aluminium windows
DUOLINE 78
Timber-aluminium
- Profile depth
- 78 mm
- Glazing thickness
- 24–50 mm
- Seals
- 4
Figures depend on configuration. Conditions on the detail page.
Explore this system
Timber-aluminium windows
DUOLINE 88
Timber-aluminium
- Profile depth
- 88 mm
- Glazing thickness
- 32–58 mm
- Seals
- 4
Figures depend on configuration. Conditions on the detail page.
Explore this systemTwo materials, one coordinated window
Total installation depths are 82, 92 or 102 mm. Coordinate interior and exterior colours, facade connections and glazing from the measurement stage.
DUOLINE · 2026
Timber-aluminium · DUOLINE
The natural character of timber, with or without exterior aluminium cladding. Explore the six SOFTLINE and DUOLINE systems in our 2026 brochure for renovation and new construction.
Download the brochurePDF · 14 pages · French
Compare profiles and glazing
DUOLINE 68Show specifications
- Material
- Timber-aluminium
- Timber frame (mm)
- 68
- Total depth (mm)
- 82
- Seals
- 4
- Glazing (mm)
- 24–44
- Uw / Ug (W/m²K)
- 0,90 / 0,6
DUOLINE 78Show specifications
- Material
- Timber-aluminium
- Timber frame (mm)
- 78
- Total depth (mm)
- 92
- Seals
- 4
- Glazing (mm)
- 24–50
- Uw / Ug (W/m²K)
- 0,80 / 0,5
DUOLINE 88Show specifications
- Material
- Timber-aluminium
- Timber frame (mm)
- 88
- Total depth (mm)
- 102
- Seals
- 4
- Glazing (mm)
- 32–58
- Uw / Ug (W/m²K)
- 0,79 / 0,5
| System | Material | Timber frame (mm) | Total depth (mm) | Seals | Glazing (mm) | Uw / Ug (W/m²K) |
|---|---|---|---|---|---|---|
| DUOLINE 68 | Timber-aluminium | 68 | 82 | 4 | 24–44 | 0,90 / 0,6 |
| DUOLINE 78 | Timber-aluminium | 78 | 92 | 4 | 24–50 | 0,80 / 0,5 |
| DUOLINE 88 | Timber-aluminium | 88 | 102 | 4 | 32–58 | 0,79 / 0,5 |
Source: BO Fenster 2026 brochure, pp. 3–8 and 13. Uw refers to the window, Ug to the glazing. Uw values are calculated with a thermally insulating Swisspacer spacer. Actual performance depends on dimensions, glazing and options; final specifications are provided in your quotation. DUOLINE total depths include 14 mm of aluminium cladding; seal counts follow the brochure comparison table.
SOFTLINE · the character of timber
68, 78 or 88 mm profiles in laminated pine or meranti. Custom shapes and decorative elements can suit the building, including heritage projects subject to their requirements. An aluminium profile protects the bottom of the sash.
DUOLINE · timber inside, aluminium outside
The 68, 78 or 88 mm timber profiles have an additional 14 mm aluminium cladding. Total installation depths are therefore 82, 92 or 102 mm. Exterior finishes can be selected from the RAL colour range.
Timber species & finishes
Pine and meranti with four protective coats. Opaque paints or stains that reveal the grain, including white, light oak, walnut, teak, graphite and olive green. Colours vary by timber species; confirm your selection with a sample.
Hardware & glazing
MACO MULTI-MATIC hardware with two security keeps, micro-ventilation on tilt-turn sashes and aluminium handles. Decorative or functional glazing and Swisspacer Ultimate spacers depending on configuration. Optional handles with keys or safety buttons.
Timber finishes
View data sheet · PDF (FR)Timber-aluminium windows
A proposal suited to your building
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