Installation of a Single Flat Roof Window – Flat Glass Top Unit ISG 2093 with Vented Bottom Unit CVP
The assembly consists of a flat glass top unit and a sashed bottom unit. The top unit - VELUX ISG 2093 is combined with the VELUX CVP sashed base frame featuring an insulated glazing unit. The top unit is constructed from aluminium profiles with a toughened glass pane, while the flat roof window frame is made of maintenance-free white PVC.
Why choose Vented ISG with CVP?
The combination of the VELUX ISG 2093 flat glass top unit and the VELUX CVP vented bottom unit offers a sleek architectural appearance, excellent thermal performance, outstanding cost efficiency, and the added benefit of natural ventilation. It is an ideal solution for projects that require maximum value without compromising quality, performance, or design. The vented configuration helps improve indoor comfort and supports healthy indoor environments through natural ventilation. It is also compatible with electric operation and the full range of VELUX control solutions, making it easy to integrate into modern, connected buildings.
A key advantage of this Installation Type is that it includes all eight standard VELUX flat roof window sizes for this configuration of top and bottom units.
Easily compare different window sizes throughout the concept phase to assess daylight potential, proportions, and the overall architectural impact before selecting the final solution.
As the project progresses, this Installation Type can be refined into a fully specified VELUX flat roof window with complete technical data, product characteristics, and the full range of available configuration options.
Installation Type – Object Type Description
Speed up your early design workflow with pre-defined VELUX installation solutions.
Installation Types allow you to quickly explore daylight concepts, roof layouts, window sizes, and roof window placement without committing to detailed product specifications too early in the project.
These lightweight BIM objects are specifically developed for the concept and schematic design phases. Geometry and product information are intentionally simplified, allowing you to focus on architectural layout, daylight performance, proportions, and overall design intent while maintaining maximum flexibility for later project development.
Compare different roof window sizes to evaluate daylight potential, proportions, and visual impact before committing to a final specification. As the project develops, this Installation Type can be refined into a fully specified VELUX roof window with technical data, operation type, glazing, finishes, blinds, shutters, and accessories.
Choosing between a fixed or a vented flat roof window is an important early-stage design decision. Beyond daylight, the choice affects the building's natural ventilation strategy, installation planning, and, for electrically operated windows, early coordination of the power supply. As fixed and vented units are different product systems, changing from one to the other after installation typically requires complete replacement of the window, making early specification both practical and cost-effective.
When the project reaches the specification stage, simply select the VELUX product configuration that best matches your technical and performance requirements.
Key Benefits
- Complete roof window system solution
- All eight VELUX flat roof window sizes available for this configuration
- 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
Size Table (all dimensions in mm)
| Code |
Sa |
Sb |
Fa |
Fb |
La |
Lb |
Ra |
Rb |
Ea |
Eb |
Aa |
Ab |
| 60060 |
435 |
435 |
463 |
463 |
559 |
559 |
600 |
600 |
780 |
780 |
784 |
784 |
| 60090 |
435 |
735 |
463 |
763 |
559 |
859 |
600 |
900 |
780 |
1080 |
784 |
1084 |
| 80080 |
635 |
635 |
663 |
663 |
759 |
759 |
800 |
800 |
980 |
980 |
984 |
984 |
| 90090 |
735 |
735 |
763 |
763 |
859 |
859 |
900 |
900 |
1080 |
1080 |
1084 |
1084 |
| 90120 |
735 |
1035 |
763 |
1063 |
859 |
1159 |
900 |
1200 |
1080 |
1380 |
1084 |
1384 |
| 100100 |
835 |
835 |
863 |
863 |
959 |
959 |
1000 |
1000 |
1180 |
1180 |
1184 |
1184 |
| 100150 |
835 |
1335 |
863 |
1363 |
959 |
1459 |
1000 |
1500 |
1180 |
1680 |
1184 |
1684 |
| 120120 |
1035 |
1035 |
1063 |
1063 |
1159 |
1159 |
1200 |
1200 |
1380 |
1380 |
1384 |
1384 |
Table legend:
Sa/b - Sash aperture,
Fa/b - Frame aperture,
La/b - Lining groove,
Ra/b - Roof opening,
Ea/b - Ext. frame,
Aa/b - Top glazing unit
For more guidance, please download the DWG and PDF documents with the detailed cross sections of the product with dimension lines!
| Code |
La (m) |
Lb (m) |
Effective daylight area (m²) |
|
|
|
| 60060 |
0.559 |
0.559 |
0.31 |
|
|
|
| 60090 |
0.559 |
0.859 |
0.48 |
|
|
|
| 80080 |
0.759 |
0.759 |
0.58 |
|
|
|
| 90090 |
0.859 |
0.859 |
0.74 |
|
|
|
| 90120 |
0.859 |
1.159 |
1.00 |
|
|
|
| 100100 |
0.959 |
0.959 |
0.92 |
|
|
|
| 100150 |
0.959 |
1.459 |
1.40 |
|
|
|
| 120120 |
1.159 |
1.159 |
1.34 | |
|
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