Richard and Felicia almost singlehandedly turn an underground water reservoir in the Humber Estuary into a family home. It's an epic task. And then a life threatening illness strikes.

After recovering from leukaemia, Toby is driven to build a complex home around an old oak tree. But can he balance high architecture and health with a comfy family place?

Andy and Jeanette plan a precarious cliff-top build on the west coast of Scotland. There are battles with extreme weather, budget overruns, and a sudden emotional shock.

Paul and Amy Wilkinson plan to build a lakeside home in Lincolnshire with five circular timber buildings linked by walkways. But Paul's health suffers as he struggles to finish in a year.

Design engineer Mark Butler is paralysed from the waist down and needs a cutting-edge, wheelchair-friendly family home. Making it for £600k proves a huge emotional strain.

Edward and Hazel plan a shining white art deco lighthouse on a rugged beautiful clifftop. But almost immediately their wildly optimistic plan runs into trouble.

Six years on, Kevin returns to Scotland to see Colin and Marta's incredible metal home, inspired by aircraft hangars, now that the construction is finally finished.