Roofing ventilation help needed please

[5teves]

Hi,

I'm really concerned about the roof structure we currently have and the ventilation it will need once we insulate and plasterboard the ceiling.

This is a existing outbuilding and the roof is made up of doubled up 4x2 treated timber. They span 4.7meteres, They run sideways, With the firings running perpendicular to it as the fall was created towards to run towards the back of the garden,
The rokf is finished off with osb3 boards and fibreglass resin.

We would lile to now insulate and plasterboard the ceiling but worried about the ventilation for the roof.

The concern arises becuase currently the only ventilation gap is under the sofit, but because the joist run perpendicular we feel this will most likely block the ventilation massively. Yes gap created by the firings does leave some space for the air to travel but i dont think it will be enough.

Please can someone advise what is the best solution to this concern. We were thinking if maybe cutting oit some ventilation holes to the side but really not sure what the correct this to do is.

We would appreciate some advise so much.

Thanks in advance

 

[Swwils]

You can get retrofittable plastic baffles that will ensure any insulation doesn't block the path from the soffit vent.

 

[5teves]

You can get retrofittable plastic baffles that will ensure any insulation doesn't block the path from the soffit vent.

Hi swwills, thanks for your reply but im worried about the the actual space available for the ventilation in the first place.

I understand your solution will prevent the insulation reducing the ventialtion space any further, however my concern is that because the joists run perpendicular to the fall of the roof and the soffit board is naturally at theend of the fall, i feel that when air is let in the soffit vents, it will be reduced by the first joist which is 400mm away running perpendicular and then so on....