On Jun 26, 4:47 pm, "bent" wrote:
the air, if effeciently exchanged may be less, but I've been readinghttp://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?id=...
and the air in there could be 150 it seems, besides I have dark brown
shingles


It can be 150 with poor attic ventilation and no whole house fan.
But it isn't going to be 150 with any reasonable amount of attic
venting and a whole house fan pushing a huge volume of air in there.
With lots of soffit venting that you have, plus 2 peak vents, there is
quite a bit of area for the whole house fan to push air out of.

And when do u expect to use the whole house fan? It's of most use
when you have cool outside air, like days when it cools off quickly at
night. In many climates, there aren't that many days that make it
practical. For example, it does nothing about humidity, which further
limits it's use. And on days when the attic might be 150, it's going
to be 90 outside and most people would have AC on.

Bottom line, in cases where the attic could reach 150, the solution is
more attic venting, with or without a whole house fan. And I think
the best way to do that is with a ridge vent.