LBackup instructs RSync to preserve permissions by default.

To preserve permissions on local volumes under OS X it is important to ensure that the “Ignore Permissions” options is unselected on your backup drive. If this options is selected then the permissions are ignored and it will not be possible for Backup to preserve the permissions of directories and files copied to the backup volume(s). Therefore, it is recommended that this option is left un-checked on source and destination volumes. Although backups may work with this option checked, it is not tested or recommended.

To set this option on and off first select the drive. Next select 'Get Info…' under the 'File' drop down menu. Finally, either check or un-check the appropriate check box. You may need to first click the disclosure triangle for the drive permissions.

It is also possible to check and even enable these permissions from the command line :

vsdbutil -c /Volumes/VolumeName

sudo vsdbutil -a /Volumes/VolumeName

sudo vsdbutil -d /Volumes/VolumeName

It is also recommended that you ensure access control lists are enabled on any backup volumes.