The easiest way to achieve that is to have your home on a separate partition beforehand.
When installing a distribution, the partition that will contain the system is usually reformatted, deleting everything in it. But if you used another partition for your home, you can select it during installation to be used as such, without reformatting it, thus keeping the data on it.
But if you aren’t in that setup already, backuping is indeed your only possibility.