I have lately been putting energy into my web pages, instead of this
blog. Since more people come here, I should transfer web site
information sometimes, to be in both places. I apologize for the
redundancy, and will do this with limits. Here is a first installment.
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
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will be withdrawn and reset, to place the next batt.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.