How to get air flow in to a flat roof

[malawihap]

What is the best way to get air flow in to a flat roof that is going to be insulated . I have a plastic facia going around the shed do i have to drill through this on both side's of the shed or is there a better way .

 

[masona]

Is the fasica flat on the wall ? or do you have a soffit which is underneath the fasica.

 

[malawihap]

The fasica is flat to the wall

 

[masona]

1,If you can take the fascia off then put a thin batten (top & bottom)across the end of the joists,then re-fix the fascia, so the fascia is sticking out slightly to let the air flow entering the bottom.

2,Or you could lower or cut the top of the fascia approx 10mm gap to allow the air flow to the top.

3,Or if you have guttering then remove and drill a few hole then replace gutter back again to hide the holes.

4.Or you could use fascia air vent

 

[malawihap]

Do i need to do this on opposite sides all sides or just 1 side.

 

[masona]

Both side would be better for continue air flow otherwise trapped air