Shaped (triangular) windows bead on outside

[DC5]

Hi folks,

Our triangular shaped windows were fitted at the weekend and I helped in this process due to the weight and size - they are in the gable end above bifolds.

I mentioned that the beads are on the outside where normally I have seen them inside before.

They are triple glazed aluminium by Aluk. 
The installer said that the weather seal was in the beads, the windows were marked and the drain holes were to the front!

They look great and I’m happy but would be reassured to hear this is (or is not) normal!?

 Thanks 

[Mr Punter]

If they are externally glazed you have the beads external.  Drain holes are obvs leading to outside.

[joe90]

If the beads are external the glass usually has anti-removal brackets (so a burglar can’t remove the beads then the glass to gain access.)