BuddyPress.org

I’ve used this website before as an example and I hope he doesn’t mind, but check out leadpress.com as an example.

You’re not running BuddyPress in a sub directory, but actually just stopping it from taking over the root and /blog URLs, and instead using the normal WordPress way of assigning pages.

Rename home.php to community.php.

Use the Page Template method to name that page template “Community.”

In the blog admin, Make a page for your home, a page for your blog, and a page for your community, all with similar slugs.

The community page will use the “Community” page template.

Goto your blog settings and assign the front page to be the page you made for home, and make the index/blog page the one you made for your blog.

Then, you will want to install bbPress in a folder called “/community/forums/” and be sure to create a page with the slug “forums” as a sub page of “community”

That should do it?