yard units for buying limestone screening

[tokiwadai]

I'm buying limestone screening for my backyard patio project.
The shop is using yard measurement units for the volume, that I am not used to use.

What I know is 1 yard equal to 3 feet, which a unit for length, not volume.
Does this means 1 yard of limestone screening means 27 cubic feet (3'x 3'x3')?

Thanks in advance...

[Kanus]

You are correct. People typically refer to a "cubic yard" (27 cu. ft.) as a "yard". Likewise a "cubic metre" is often called a "metre"