Non-typical roof structure... How to insulate?

[tommy1980]

Hi everyone. I hope someone might have an idea for me. I have stripped out the ceilings in our summer house and plan to open it up and vault the ceilings.

My issue is the direction of the supporting rules. If I insulate between the rules, instead of putting back the low ceilings, I'm not sure how to ensure airflow behind the insulation as it is trapped by the rules.

A guy told me to just use spray insulation and forget about it.

Does anyone else have a suggestion?

Any help is greatly appreciated!

 

[Daniel 109]

One possible solution is to put the isolation on the outside of the roof.

 

[tommy1980]

One possible solution is to put the isolation on the outside of the roof.

Indeed it is but that's a lot more effort and cost than needed right now. We've just recently extended and the old and new roofs would also be out of alignment. If all else fails I'll keep it in mind.