SteveB wrote:

I live in Las Vegas. We use evaporative coolers here. I want to add a
5,000 cfm for one side of my house.

Wow.

I got a bid from a "friend" who is a licensed HVAC person. 24' of 14" dia.
spiral...

With a 5000cfm/1.07ft^2 = 4677 fpm (54 mph) air velocity?


Nick