"Hi Tom, thanks for reaching out! You can definitely connect more than three Google Wifi points. As each point covers up to 1,500 sq. ft., most houses will not need more than three. However, you can add as many as you need to cover your space. We've found that even very large homes don't need more than six points, though.

Hope this helps! Let me know if you have any more questions.

Courtney
OnHub Support"
https://productforums.google.com/forum/#!msg/googlewifi/dItJbdG0ax0/pz_7k-FFDAAJ