Here is the overview of the diskspace requirements for the new service pack for Windows 7 and Windows Server 2008 R2.
Disk space requirements
Make sure you have enough free disk space to install SP1 (even though much of that space will be reclaimed after the installation). If you need to create free disk space, go to Strategies for freeing disk space on the Windows website.
|Installation method||Estimated amount of free disk space required|
|Downloading SP1 from the Microsoft website||
|Installing SP1 using an installation DVD||