Yes! If your membership is set to open to all, your rooms will always be public. If your membership is set to by approval or invite-only, House admins can make House rooms public for all when creating a room.
To make a room public while creating an event:
1. Tap schedule next event in the event scheduling section
2. Add your event details
3. Scroll to the bottom and toggle public room
To make a private room public:
1. Tap the ...menu at the top right of the room
2. Tap make this room public