Are there any actual solutions to this issue - other than waiting for Avast?
I have about 1gb of free space left right now -
Generally there isn't other than to wait for the avast housekeeping to kick in.
What is your system and the size of your HDD ?
What is your OS ?
1GB of free space is an indication you should be looking at what programs you have installed and removal of those not used in a long time, get an external HDD and hive off some data files, media or image files or consider getting a new larger HDD and clone your existing installation on to that. Most people have way more than 1GB of RAM so having 1GB left on your HDD is BAD.
Windows doesn't like it getting less than 15% free space, as that doesn't allow for certain functions, defragmentation, swap file use, etc.