What size dumpster do I need?
 

I'm going to be removing 3 layers of shingles - 1 layer wood shake, 2 layers composite. What size dumpster do I need?

Might want to let us in on how many squares it is for a better guess.

Ha! Forgot the most important part. It's 16 squares.

20 yard should do it.

Shakes are pretty voluminous so if you are worried...go 30 yard.

Might get by with a 30 yd. dumpster.
I like the kind with a door on the back so a wheel barrow can be rolled in and low enough sides that you can load from both sides.
Do not get one to small, not only will it not hold everything, but the truck that's going to need to lift it will be to small to pick it up. Not fun after loading it to have to then take them back out. (been there).