Typically 80-110 lbs, but there is a range.
The weight comes down to the size of the unit. Our most common size 12"x15"x72" in a 2-Tier configuration is 90lbs (most will be in that ballpark).
Our largest standard unit 24"x24"x72" in a 6-Tier configuration is 240lbs.
For more specific model weights send us and email at firstname.lastname@example.org.