Gutterless gable house – rainscreen ventilation doubts
Imagine a small house, with a gable roof, it would be a “barn” type of building.
Entirely wrapped in wood boards (roof included), there’s no eaves nor gutters, all rain water will be handled with a perimeter “in ground gutter”.
Walls will be be insulated with fiberglass batts, and 2″ exterior rigid foil faced, staggered and taped. The roof would be similar, cathedral ceiling, blown-in insulation, spray foam inside to seal everything, and 2 ” of rigid outside. In theory it would be pretty well insulated and air tight.
Now, the whole house would be wrapped in wood boards, forming a rainscreen, here’s my question; do I have to ventilate the ridge in order for the rain screen to work?
The only “proper air intake” it’s in the bottom, with either a insect screen or coravent strip, however the board siding isn’t exactly sealed tight between boards, it supposed to be a bit “rough”. Air (and for that matter water) could leak everywhere.
Here’s a link to a similar house in England, this is what I mean:
Thanks for any input.
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