Both Kits and Building Blocks can be easily downloaded from the website. You can also copy and paste individual Building Blocks into Foundation projects. After installing the new 2.2.0 version of the Foundation CLI, Building Blocks and Kits can even be downloaded and installed automatically into ZURB stack projects, available instantly as ready-to-use partials. Simply run npm install -g foundation-cli@2.2.0 and then foundation kits install in any project for Kits or foundation blocks install for individual Building Blocks.
We've been using Building Blocks internally in our client work to give ourselves a head start in our projects, and we've seen our development time cut in half. We're excited to see the Foundation Building Blocks library continue to grow with new Building Blocks and Kits from the ZURB team and our amazing community of Foundation users!