Velux leaks below 15 degrees

[Rustychain]

Can anyone tell me why this happens? Is it because the window and it's seals leak, or is it because of the flashings?

The reason I ask is because I'm trying to find an affordable solution for the extension we're having built (12 degrees roof). The 'flat roof' velux windows are all well and good, but are expensive and also not that attractive. I was thinking that if the flashing were the weak point, I might be able to engineer this out with extended flashings etc.

Experiences/advice welcomed (even if it's "dig deeper in those deep pockets of yours"! )

Thanks

 

[Deluks]

The problem with low pitch is that the wind can blow rainwater up the roof.
You can get Velux for flat roofs, I think you might need an upstand of some sort.

 

[Rustychain]

Thanks for the response. They do supply a flat roof version with an upstand, but it's not that attractive (IMO). It also costs three times as much as a normal velux....