George Clarke's Amazing Spaces (C4, 8pm)

THOSE who suspect I'm a fan of the amiable Wearside-born architect are on the right lines. It also helps that he's from the North-East and back to present another humour-filled series about making the most of very little.

Asked about his favourite conversion, Clarke goes back to his early days of creating quirky but well-qualified parts of outdoor life.

"The caravan we converted for me and my kids in series one was extreme even for me. I bought a dilapidated 1974 knackered static caravan for £300. Everyone said I’d been ripped off. We then spent the next few months pimping the space – we reconfigured the design, gave it new electrics, insulation. People still can’t believe what we achieved. The before/after transformation was incredible – the most extreme I've worked on," he says.

Tonight he reaches a project which my family would adore if it wasn't for all those thoughts of seasickness, because George and collaborator Will Hardy decided to reinvent the great British beach hut, and want to put one on the water. Which, of course, makes it a sea hut. Also featured is a young architect who has just landed his first commission – to design a unique garden pavilion. The problem is his ultra-demanding client – who also happens to be his grandmother.

Elsewhere, Norfolk sculptor Peter is building a cartoon cabin on wheels in his cliff-top garden with a retractable roof. I'm not sure Mr Clarke will enjoy Peter's decision to improvise everything from reclaimed materials.

George counts being an architect as his full-time job rather than TV presenting.

"First and foremost I'm an architect, a builder and a developer – that's what I love doing," he says. "All it means is I work all the time. On the train I'll do a batch of sketches and drawings for a scheme we're doing.

"Actually, that just goes to show how technology can effect something like that. I'll take a few photos of the sketches on my iPhone and send them back to the office so they can get cracking on what they've got to get done for the day."

And as for his rather over-used expression of amazing and what makes an amazing space, he says: "An Amazing Space is somewhere that you just think ‘wow’ when you walk in, when you instinctively have a positive reaction. After you think it’s a great design that uses interesting building materials, fantastic skylights or materials or natural light in an inventive way that might give a magical view of the landscape. But when you walk in and you’ve automatically got a smile on your face, and the space is just beautiful, that’s when it’s amazing."

Who Do You Think You Are? (BBC1, 9pm)

ACTRESS Anne Reid is keen to find out about her father's family, but only has a couple of clues to go on – the name of a house in Scotland and an old story that his ancestors were ministers in the church. This puts her on the trail of her great-great-grandfather John Reid in Fife, who turns out to have been a teacher and not a minister. However, he also had a less-honest sideline which ended up with John being transported to Tasmania on a convict ship for forgery. She heads to Oz to see how her ancestor fared as part of a labour gang.

Stephen Fry in Central America (ITV, 9pm)

Stephen's travels continue in Costa Rica, where he encounters poison-dart frogs and falls in love with a baby sloth at a biological research station. But he soon finds there is more to the country than conservation and eco-tourism as he ascends volcanoes, descends white-water rivers and experiences the passion of a football derby in the capital of San Jose. He then crosses over into Panama for the final leg of his trip, witnessing giant leatherback turtles coming ashore to lay their eggs and learning how to dredge the canal in Panama City.