Plywood Baffles

I no longer accept that expanded polystyrene or cardboard baffles have acceptable durability. Cardboard baffles see driven moisture, and decompose. At elevated temperature, EPS evaporates.

This baffle for 24" oc 2x4 roof joists, has dimensions 22" x 24". Plywood is 1/2" thickness CDX. 3/8" thickness is ample for future jobs.

I place top-layer insulation batts, here Johns Manville AU333, R19, 24" x 48", all the way out to the exterior wall. The adjacent baffle here will be withdrawn and reset, to place the next batt.

Here is a look down into a finished vent pocket. Insulation under the baffle is protected against soaking or other insult, by driven weather. I will learn to shorten nearest baffle support legs, to give a little more room for insulation. This baffle clearance is much larger than area in the soffit screen.