OOOOps, sorry Jerry. Another slightly misworded statement. What I should have said that if you have no idea what is under them thar shingles/roofing 'I' would write it up. Even if it is "an approved design" it still does not answer all the issues of why you should ventilate it anyway.

An attic with no roof top ventilation will kill any life expectancy of any shingle with the heat build up in the attic. The insulation in that ceiling is not going to perform as it should due to the excessive heat build up. You (him, they, me, I)could put heat reflective foil under the shingles but I do not know of shingle manufacturers that won't void the warranty.

Here I go. Am I actually going to say this to Jerry P.

Approved system or not there are multiple reasons why you would ventilate any roof/attic/enclosed space. I cannot see thru roofing material. The system is more than just likely not to be in place. I write it up as such.

I do give my reasoning to the client/whom ever for writing it up. They can do with it as they wish.

Ted