In Glasgow, we catch up with Amanda and Chris, who turned their cramped house into a fab family home, and Joanna and Ben, who built a Wild West-inspired abode on the same street.

Shop owner and jewellery maker Karen builds her version of a mountain hut in central Glasgow, inspired by hikes in the Scottish Highlands. After waiting five-years to get started, the project leaps into action when Karen and her neighbour agree to lay out their foundations together using the same contractor. Retiree William is building an old-style home next door, the pair come across some hurdles building next to each other.

Jonathan uses a new experimental system that uses wooden boxes held together with only bolts to build his home in York. With a plan to build three storeys, it will be the largest structure ever made using this method.

At Graven Hill, Tom and Lori hope to hit the ground running with their self-build adventure of a lifetime. But it quickly turns into a nightmare they could never have imagined.

Kevin and Natasha meet couple Jane and Richard who are building houses three doors down from each other in hopes of providing a new life for the five children they have between them. But where Jane's plan involves a beautifully crafted home with a high-end kitchen, Richard is planning on building a minimal and sleek property with some special architectural moments.

Tim plans to move from his small flat in Bicester into an architecturally daring home at the UK's largest mass self-build site in Graven Hill. With the help of his dad Michael, the project is supposed to be a chance to spend quality time together outside of work but the stress begins to ramp up when the five-tonne car lift Tim ordered from China doesn't fit into the specially prepared hole in the basement. Plus, Kevin and Natasha revisit Jitinder, whose house was unfinished due to the moisture problems and his resin floor last time they met, now they experience the full splendour of his Hollywood Hills style home.

In Yorkshire, Nicola gives a traditional redbrick home a modern twist, but will it work? Matt and Maryellen create a Brazilian-inspired home with flamboyant colours, textures and a butterfly roof.