William W. Plummer wrote:
Joseph Meehan wrote:

All the air that does go through the system is "sucked" up
through the soffit vents. Where else do you think it is going to
come from???
AND out the ridge vents, which you must have for all the reasons
mentioned.

And in-between it will leave moisture in the attic. Not good!


One thing that can also bit people in the butt is that when venting
moist
warm air vertically, you increase the chance of condensation flowing
back
in from the vent.
In winter especially the relative humidity of the vented air drops
dramatically. Even in summer with humid outside air, if it isn't
raining in your attic, the fan exhause won't start it.

We are talking about a bathroom fan.


Lots of insulation would be advisable. (not sure
if your in
a warm climate or cold)
That I can generally agree with.
I disagree. Insulation does not add heat. It is a barrier that
prevents heat flow.

I believe you snipped a little too much and lost the context.

"One thing that can also bit people in the butt is that when venting
moist warm air vertically, you increase the chance of condensation flowing
back in from the vent. Lots of insulation would be advisable."

So it appears Bocestb was suggesting insulation around the duct to keep
it warm (not add heat as it would already be warm) to reduce condensation.

Your insulation layer is what divides "inside"
from "outside". Your attic should be outside so the insulation must
be on/under the attic floor. That insulation will not affect far
exhaust into the attic.

--
Joseph Meehan

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