On Thu, 27 Apr 2006 22:31:39 -0400, "Walter Cohen"
wrote:

Well, I'm trying to get the most bang for the buck. If the attic will be
stiffling (and it usually is in the summer even with the window open) then

I'm coming in in the middle of the thread. I have an unfinished attic
with no window, and a trap door between the attic and the second
floor.

I'd want to try to circulate and remove as much of that hot air as quickly
as possible. The turbine would probably take quite a while [longer] to move
as much air as the powered attic fan.
If my upstairs A/C is working against the heat build up in the attic and
surrounding room walls and roof top then I wonder if the extra electricity
to run the attic fan would save me the amount of extra energy expended by
the AC trying to cool the upstairs, as the attic space would have been
hopefully cooled sufficiently by the fan.
Does that make any sense?

I love my electric roof fan. It took 10 degrees off my second floor,
and the townhouse already had full width soffitt vents front and back
and a full width ridge vent. I don't use AC at all normally, live in
Baltimore, and when I bought the house the first summer, it was too
hot to go upstairs at all after work. I would sleep in the basement
and go upstairs in the morning to wash and get new clothes. After the
fan the upstairs was usable to change clothes, watch tv or work at my
desk, and sleep. A couple weeks a summer are still pretty hot.

The fan keeps the attic from ever gettting that hot. It goes on
around 10 or 11 in the morning and turns off between 6 and 10PM, so it
makes no noise when I'm trying to sleep.

There is so much circulation now that after 15 or 18 years I found a
layer of "lint" on all of the soffitt vent screens, like one find on a
clothes dryer screen but not nearly as heavy. None of my neighbors
had that. I peeled it off.

It's possible I need more insulation in the attic "floor". The
fiberglass only comes up to the top of the joists, and I thought that
was enough. I have to get more info about that.

If you refer to an attic fan, some will think you mean what others
call a whole house fan, a fan in the ceiling of the second floor, that
only works when it has gotten sufficiently cool out side, and which
some use while they are sleeping. Too much noise.

Thanks,
Walter
rob wrote in message ...
On Sun, 23 Apr 2006 11:00:46 -0400, "Walter Cohen"
wrote:

Perhaps I might be better served by an adequately sized power attic fan,
thermostatically controlled.

Walter


They work but eventually they will require some maintenance and you
will be paying for electricity to save electricity.



Your question makes sense but I can't answer that without knowing more
facts. Probably best to ask some local a/c guys where you are. Maybe
another thing to consider is a roof ridge vent tho its probably more
economical when you are replacing your roof.