Hanging steel ducts

Don't know about wire--most use perforated strap often referrred to as "plumber's strap". As to where to get it, HD/Lowes, any other hardware store or lumber yard, a plumbing or a/c supply house -- all should have it. It comes in a roll about 5-6" in diameter, but I must confess that I don't remember how many feet is in the roll. It is not terribly expensive. Some places also have a small roll that is probably around

6-8', but if you figure the price per foot, it is MUCH cheaper to get the large roll. Once you have some, you will be surprised at how many uses you can find for it--can come in real handy. BTW, I didn't ask, but assume you are talking about average sized residential air duct. You can use a double thickness of the strap if it looks like whatever you are mounting may be a little heavy for a single thickness. They used to make the stuff much thicker than they do now, so doubling it is needed more often. Just be careful working with it- the edges are sharp and can cut the crap out of your hands. Larry

you don't have to be too fussy. something easy to work with between 14 and 18 guage. galvinized. any hardware store. or 1" L brackets screwed into sides and then into joist. you can make your own brackets out of scrap sheet metal.