Water entering through a VELUX window is not common, and a number of factors may cause water to be visible internally.

We would ask you to check the below points on your window, to see if this resolves any water entry.

Ensure the window is fully closed and locked.
Check for internal condensation. When you see water on the interior of windows, it could also be caused by condensation. This can occur when warm, humid air comes into contact with cool glass/pane, which is especially common in the winter. You can find more information on condensation and some tips around condensation here.
Check for any obvious damage or loose coverings on the outside of your window.
If the issue persists, please contact VELUX via this form.

Flat roof windows

The construction of a flat roof window, makes it very difficult for water to enter through the window itself. When the window is installed fully and correctly, the top cover drains water onto the roofing material. If any water enters through the fixings for the polycarbonate top cover, this water is then drained out onto the roofing material through small weep holes in the corner of the frame.

Therefore the most common issue that presents water internally, is an issue with the roofing material and the weathering around the window frame. We would therefore recommend contacting the original installer, or an alternative installer/roofer to check the roofing material around the window for damage.

If the water is appearing on top of the internal glazing, between the window and the top cover, this may suggest that excessive moisture has been trapped between the top cover and the window during installation. For more information on how to resolve this, please click here.

If you are still experiencing an issue with your flat roof window, please contact VELUX via this form.

What should I do when my windows appear to be leaking?