volume_info_2008r2+.sql

SELECT DISTINCT vs.volume_mount_point, vs.file_system_type, 
vs.logical_volume_name, CONVERT(DECIMAL(18,2),vs.total_bytes/1073741824.0) AS [Total Size (GB)],
CONVERT(DECIMAL(18,2), vs.available_bytes/1073741824.0) AS [Available Size (GB)],  
CONVERT(DECIMAL(18,2), vs.available_bytes * 1. / vs.total_bytes * 100.) AS [Space Free %]
FROM sys.master_files AS f WITH (NOLOCK)
CROSS APPLY sys.dm_os_volume_stats(f.database_id, f.[file_id]) AS vs 
ORDER BY vs.volume_mount_point OPTION (RECOMPILE);