Installation of a single window for sloped roofs - the system solution
The system solution includes flashing with integrated thermal insulation, underfelt collar, vapour barrier collar, external heat protection, interior solar shading, interior lining, and insect screen options. All components are designed to work together, supporting energy efficiency, indoor comfort, weather resistance, and ease of installation.
Installation type - Object Type Description
Speed up your early design process with pre-defined VELUX installation solutions.
Use Installation Types to quickly explore daylight concepts, roof layouts, window sizes, and roof window placements without committing to detailed product specifications too early in the project.
These lightweight BIM objects are specifically developed for concept and schematic design stages. Geometry and product information are intentionally simplified, allowing you to focus on space, daylight, proportions, and overall design intent while maintaining maximum flexibility for later project development.
Switch between different roof window sizes and configurations to identify the solution that best fits your design. Once the project requirements become clearer, refine the selected Installation Type into specific VELUX roof windows with detailed performance data, operation type, glazing, finishes, blinds, shutters, and accessories.
When your project requires detailed geometry and specification-ready product information, continue the design process using CoBIM and the VELUX Revit Add-in.
Why choose Single?
This Installation Type is intentionally lightweight and optimized for concept design. Geometry and product information are simplified, allowing you to quickly explore roof layouts, daylight concepts, and window placements without being locked into detailed product specifications too early.
A key advantage of this object is that it includes all 27 standard VELUX roof window sizes. Since VELUX roof windows are generally manufactured according to this size grid, having all standard sizes readily available allows you to quickly test different configurations and identify the best fit for the available roof geometry.
Switch between sizes during the design process to compare daylight potential, proportions, and spatial impact before committing to a final specification.
Once the project requirements become clearer, the selected Installation Type can be refined into specific VELUX roof windows with detailed performance data, glazing options, operation type, finishes, blinds, shutters, and accessories.
For later project stages requiring detailed geometry and specification-ready product data, we recommend using CoBIM and the VELUX Revit Add-in.
Key Benefits
- Complete roof window system solution
- All 27 standard VELUX roof window sizes available (BK, CK, FK, MK, PK, SK, UK)
- Faster early-stage design and decision-making
- Easy comparison of different window sizes and layouts
- Coordinated installation products and accessories
- Integrated solar and heat protection options
- Consistent VELUX detailing and performance
Window Code |
Width in mm |
Height in mm |
Effective Daylight Area in m2 |
| BK04 |
472 |
978 |
0.23 |
| CK01 |
550 |
698 |
0.19 |
| CK02 |
550 |
778 |
0.22 |
| CK04 |
550 |
978 |
0.29 |
| CK06 |
550 |
1178 |
0.37 |
| FK04 |
660 |
978 |
0.38 |
| FK06 |
660 |
1178 |
0.47 |
| FK08 |
660 |
1398 |
0.58 |
| MK27 |
780 |
624 |
0.26 |
| MK04 |
780 |
978 |
0.47 |
| MK06 |
780 |
1178 |
0.59 |
| MK08 |
780 |
1398 |
0.72 |
| MK10 |
780 |
1600 |
0.85 |
| MK12 |
780 |
1800 |
0.97 |
| PK25 |
940 |
550 |
0.27 |
| PK04 |
940 |
978 |
0.60 |
| PK06 |
940 |
1178 |
0.75 |
| PK08 |
940 |
1398 |
0.92 |
| PK10 |
940 |
1600 |
1.07 |
| SK01 |
1140 |
698 |
0.48 |
| SK06 |
1140 |
1178 |
0.95 |
| SK08 |
1140 |
1398 |
1.16 |
| SK10 |
1140 |
1600 |
1.35 |
| UK04 |
1340 |
978 |
0.91 |
| UK06 |
1340 |
1178 |
1.15 |
| UK08 |
1340 |
1398 |
1.40 |
| UK10 |
1340 |
1600 |
1.63 |
Important note to the size chart:
While all 27 standard sizes are available, the following sizes (in bold in the size chart) are particularly versatile and are recommended for most projects due to their broad range of product variants and accessories: CK02, CK04, FK04, FK06, FK08, MK04, MK06, MK08, MK10, PK06, PK08, SK06 and SK08.
These sizes offer the widest selection of operation types (manual, electric and solar), interior and exterior finishes, glazing options, blinds, shutters, and smart-home compatible solutions. Choosing one of these sizes early in the design process provides the greatest flexibility when refining the specification later in the project.