"Joseph Meehan" wrote in
:

Al Bundy wrote:
"Joseph Meehan" wrote in
:
.. I suggest that proper passive (no fans) venting is usually far
better as there is little difference in real results of a active or
passive system, assuming they were both well designed and the
passive is maintenance free, energy free and silent.


Hey Joseph:

I don't understand how a fan would not be better. Moving 1600 cfm of
super heated air from an attic has got to help. I'll agree it isn't
going to drop the indoor temp 5 deg but moving 1600 (or even 1200
accounting for inefficiencies) has got to be a good thing for at
least the shingles.

Note that I wrote: ".. there is little difference in real results
of a
active or passive system..." The difference is just not worth the
cost in reliability (if the fan fails then it is blocking the passive
vent) cost of the fan, power usage, vibration and noise. Yes even a
small decrease would be good, but not enough good to outweigh the cost
in most situations.





Now noted that you are speaking of all components over time. Thanks for
the reply.

But the home inspector when you sell checks the "Excellent" box for attic
ventalation. Impresses the buyer. Some buyers probably even think that
means it air conditioned up there :-)