Previously, 32-bit Windows had a minimum storage requirement of 16GB, and 64-bit Windows needed 20GB. Both of these were extremely tight, leaving little breathing room for actual software, but technically this was enough space for everything to work. That minimum has now been bumped up: it’s 32GB for both 32- and 64-bit versions of Windows.
Part of this growth may be due to a new behavior that Microsoft is introducing with version 1903. To ensure that future updates install without difficulty, 7GB of disk space are permanently reserved for the install process. While this will avoid out-of-disk errors when updating, it represents a substantial reduction in usable space on these low-storage systems.
It’s remarkable just how much space a default Windows installation takes up – and it’s even worse just how hard it has become on Windows to even properly find out where all that space is going as your machine starts to rack up the months or even years of use. While other modern operating systems such as Linux or macOS may not be as bad as Windows, they, too are starting to treat disk space like a commodity, and they, too, can be difficult to manage.