Kevin McCloud and Natasha Huq return to Gravern Hill to catch up with Amanda and Chris and Joanna and Ben who decided to build their own houses on the UK's largest self-build site. Amanda and Chris were living just outside Glasgow in a house that became very cramped with their three children when they chose to not only build their own home but design it themselves without an architect. Joanna and Ben built an American ranch-style house and have been adding to it ever since to ensure their unique vision stands out.