Velux Skylight Adapter Air Outlet Air Conditioner

This is an adapter for a Velux roof window (GLU SK08 or GGU) to vent an exhaust hose from a mobile air conditioner to the outside. With the adapter, it is possible to lock the roof window in the first open position (see last picture). Two adapters fit exactly side by side on my window, so I can attach one inlet and one outlet hose. The original air hose from a Climia CMK 2600 fits directly onto the air outlet

Update 18.06.2026: Scaling the Width

To adjust the width of the air outlet for a different window, you can scale the left and right parts along the Z-axis. This allows you to change the total width of the air outlet so that it fits other windows as well. However, a reduction in width will lead to a smaller cross-section of the air outlet, which should be considered. Potentially, less air will pass through the air outlet

Roof Window Data:
Manufacturer: Velux 

Model: GLU (GGU is identical in construction)

Size: SK08 114 x 140 cm

Print Part Data: 

Nozzle inner diameter: 130.7 mm (134 cm²)

Nozzle outer diameter: 134.7 mm

Air outlet: 92.4 cm²

Print Recommendations:

Supports are necessary. They are difficult to remove from the left and right parts; I used pliers.
I used PETG as the material. It does not warp at the temperatures from the air conditioner. I would not use PLA because of its low melting temperature

The three printed parts must be glued together. I used hot glue.
Update 29.06.2026: The hot glue connection came undone in summer temperatures. I no longer recommend hot glue. I have not yet tried another adhesive