Gable Ends Whole House Fan & Louvre Question

[Robert11]

Hello:

Have never really thought about this much, but we have a whole-house attic fan in the gable end of our attic. It has metal flaps that close off the louvred opening when the fan is not running. When it is running, they open (automatically) due to the air flow.

Also have a louvred opening in the opposite gable end (no automatic flaps) that is open all the time.

Wouldn't I, perhaps, be better off if without these automatic-closing flaps ?

e.g., I would think that in summer it would be better to have cross flow air due to wind, etc., even if the fan was off ?

Same argument, I would think, even in the winter.

So, why do they use these automatic closing metal flaps on gable louvres ? (are they only used when there is an exhaust fan located there ?)

What advantage and usefulness are they ?

BTW: do most folks use screens over these gable louvred ends ?

Thanks, Bob

[ds549]

to keep the rain out???

[trader4]

I'm trying to figure out how a whole house fan can work when it's in one gable with the other gable open. This sounds like an attic fan, not a gable fan. A whole house fan is usually located in the upstairs ceiling, where it pulls air through the house via open windows and blows it into the attic, where it goes out via static vents.

The idea behind moving louvres on a gable fan is that they are supposed to open very wide during operation, giving a clear unblocked path for the air. Then they close, so rain, insects and animals can't get in.