As you noted slate roofs tend to allow air movement through the slates.
Slate roof ventilation requirements.
Moreover slates are vapor permeable so moisture problems at the sheathing layer are highly unlikely.
To comply with the code of practice for control of condensation in buildings bs 5250 2011 a1 2016 and the nhbc roof vents should be installed at both the eaves and ridge level.
Matthias in my judgment you can skip the ridge vent.
They are super easy to fit either for new roofs or renovating an existing one.
Near ridge of the roof.
Based on your 1100 sq.
Ventilation openings shall have a least dimension of 1 16 inch 1 6 mm minimum and 1 4 inch 6 4 mm maximum.
Eaves soffits and fascias.
To provide ventilation opening points can usually be provided on the following areas of a pitched roof.
And this guideline you ll need a minimum of.
How many slate roof vents do i need.
Enclosed attics and enclosed rafter spaces formed where ceilings are applied directly to the underside of roof rafters shall have cross ventilation for each separate space by ventilating openings protected against the entrance of rain or snow.
The ventilation requirements may vary based on the circumstances of the building.