Soffit ventilation causing strong draughts inside

[Barn896]

We have recently fitted soffits with 80mm vent grilles every 2metres on our recently converted cob barn. in the double height interior space we can feel a strong draught where previously there was none, the draught is coming from high up, the cob walls are 6m high. This draught wasn't here last winter before we had the soffits fitted....is it possible that these vents have strengthened the natural airflow of cold air into the barn.? We would welcome any thoughts.

 

[noseall]

Soffit vents vent the roof not the rooms below.

 

[rssteve]

Have you got loads of down lighters cut in the ceiling?

 

[JohnD]

Is there even a ceiling?

Have the walls been internally insulated?

Cold walls will have a downward flow of cold air down them, like a waterfall.

 

[Barn896]

We were thinking that some of the ventilation was also penetrating the open roof space via the less than straight cob wall plate where the rafters sit on top.

 

[Barn896]

There are no downlighters as it is an open insulated roof space about 6m high walls with height to top of exposed a frame about 8.5 m

 

[Barn896]

the walls are cob so they are 500mm thick and provide good insulation and breathability, however the waterfall of a downward cold draught is a good description of what we are getting. Did't get this prior to putting in the soffits and vents.!