Vented Or Non Vented Attic

A vented attic system refers specifically to having working vents in the attic.

Vented or non vented attic.

My question is how should the eave space be treated. The eaves will extend 12 from the rough framed walls. Fill with spray foam after installing non vented lp smartside soffits fascia etc. Both vented and unvented attic roof designs can be used in all hygro thermal regions.

What is more significant to note is that the color of shingles and roof orientation have a more profound effect on the durability of shingles than the choice of venting or not venting double or triple the effect of venting non venting. An insulation contractor advises me to eliminate the planned roof soffit vents and seal the attic with foam. While both vented and unventilated attics are permitted in both the ibc ibc 1203 3 2 and irc r806 4 a should the wood panels get wet they may not be able to dry out and buckling or loss of structural integrity may result. Our new home design will have a non vented attic space with the underside of the roof deck between rafters insulated with r 50 closed cell foam.

This facilitates the design of unvented attics in warm and mixed climates without an additional vapor retarder but requires an additional vapor retarder element in colder regions. Those vents in the attic allow for airflow and that airflow moves the hot air and moisture out of the attic. A sealed non vented airtight attic. For example in the summer months your attic is likely going to be very hot.