Stretch wrote:

You seem to love exhaust fans.

This one would have a differential humidistat
that runs the fan when woutdoors wbasement.

If the dew point of the air outside is higher than the surface temperature
of the pipe im question, what you suggest will not work.

That seems unlikely to me. I think we need a new word now, "dryth."

Most basements and houses can store dryth.

Then again, we have Key West.

Nick