Velux bearing question

[sgg123]

Hi all,

Despite all the waffle below, in summary my question is:

Do the top and bottom roof battens, to which the velux frame brackets on to, need to attach to a rafter in the middle or will they offer adequate support by just being attached at either end on the long side rafters?

This relates in part to my previous thread https://www.diynot.com/diy/threads/trimmer-height-for-velux.624902/

I am taking a break as I am a little uncertain on a couple of things. Here are some photos to put you in the picture. I started with this, but have decided I need to move the trimmers out a little to allow for the correct reveals:

Additional pictures below show some of the strengthening rafters now removed:
Crosshatched red areas show the proposed new location of the trimmers
Red horizontal line shows proposed reveal line
You will also see a feint red line on the end of the existing central rater which I intend to cut to allow the trimmers to come across

I've trimmed the double rafters in the centre of the window space back a little to allow the trimmers to move out. This means that the top and bottom battens that will hold the window frame will span the whole opening with no central rafter to attach to - is that OK... or am I over thinking this?!

 

[catlad]

The installation batons don't require any support on a tile roof, each bracket should have one large screw into a rafter.

 

[sgg123]

The installation batons don't require any support on a tile roof, each bracket should have one large screw into a rafter.

That's great, thank you. So the top and bottom installation battens can essentially 'float' over the removed middle rafter as long as the frame brackets are screwed into the outside rafters at A, B, C and D in the pic below?

 

[catlad]

Correct.