Upgrade TFS 2010 build server to support .net 4.5
It's not necessary to install Visual Studio 2012. Just copy the files in the following folder from a computer with VS2012 installed to your build server and it should work:
C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v11.0\WebApplications\
You just need to install Visual Studio 2012 and you will be good to go.