Eave ventilation

[TobbeTiger]

In connection with insulating the sloped ceilings of my house, I want to have an air gap. Currently, there is no eaves ventilation, so I plan to drill holes. How large and how many holes should be made? Is one in each bay sufficient?

The house is a 1.5-story stone house from the 1920s. Existing insulation between the rafters (about 45 mm) will be replaced with 195 mm. The floor structure between

Planned construction: Tongue and groove boards-air gap- wood fiberboard-insulation-vapor barrier-spars and plasterboard.

 

[f91jsw]

The standard is 20-25 mm gap along the entire eaves.

 

[shomakie]

I am building a garage and there I will have 3 120mm boards with 2 gaps that are approximately 50mm in total over a length of 10.4m.