Attic Fan

[Kevin Coleman]

It is now summer in Chicago and it is starting to warm up.  As a result, the top unit of my 3flat gets extremely hot(80degs) even with the window ac units.  I had an attic fan installed in my house in Atlanta and it helped the central AC unit tremendously.  I requested a quote for a solar attic fan with the installation of another vent for the 3 flat and received a quote of $1700...ouch.  

This seems a little outrages for me.  I am sure I didn't pay more than $500 for the installation of the fan in Atlanta but that was before I was investing therefore didn't keep the best records.  Chicago is definitely more expensive than Atlanta but this seems ridiculous.  Any thoughts?