If you want something different, but aren't as concerned about performance you can use User-Mode Linux to do this, which I used to use to isolate package building as well as working around bugs in BtrFS. I have a simple script here [0] (though it relies on some setup here [1]). Although I haven't looked back at it for a bit (2016).

[0] https://rkeene.org/viewer/tmp/fakeroot.sh.htm

[1] https://rkeene.org/viewer/tmp/fakeroot.Makefile.htm