Read this:
https://foundation.zurb.com/forum/posts/19765-foundationpress-child-theme
You don’t wanna use a child theme of FoundationPress afterwards for good reasons.
And this, from the Author of FoundationPress, Ole Frederik
I created FoundationPress as a boilerplate to kickstart new projects. I’ve personally never seen the benefits of using child-themes together with FoundationPress, because the theme takes its natural form anyway as the projects progress. As you mention, it is nevertheless possible to run ‘foundation update’ to grab the latest version of the Foundation.
Use this Quickstart manual to install, worked very smoothly:
https://github.com/olefredrik/foundationpress#quickstart
Hope that helps.