Is it possible to reserve a minimum amount of space used by the volume shadow copies of a given ntfs volume under windows 2008 R2 server?

I know how to set the maximum size, but not the minimum.

For example, right now on a 800 GB drive I have reserved a maximum of 15GB for shadow copies, but the actual current size of shadow copies is only 4GB. That means the remaining 11GB are shown as free, and nothing stops Windows from using up those 11GB. 
So when the shadow copies need to grow, the space may not be available.

The drive in question is not the primary drive, and is usually at or near capacity.


Is there a way to reserve this space so that windows will take the reserve into account when displaying the free space, and when adding new files to the disk?