Oregon Shepherd’s standard “blow box” is a box of 40 pounds of loose sheep wool insulation.
Installed in vertical applications such as walls in a conventional home, target at least 0.97 pounds per cubic foot (minimum density) and up to 1.2 pounds per cubic foot (premium density), thus between 33 and 41 cubic feet per 40-pound box.
Installed in horizontal applications such as attic/ceilings or floors, target 0.92 pounds per cubic foot, thus about 43 cubic feet per box.
This product is shipped compressed to about a 6-to-1 ratio, so allow for some extra wool if you will be installing manually without an insulation blower (because a blower would help fluff the wool to the target density). Also consider extra material if installing in an application subject to settling due to vibrations, such as a van conversion.