PROPERTY show Grand Designs returns to Channel 4 this week, and presenter Kevin McCloud says that, after nearly 20 years, there is still plenty to achieve.

The 58-year-old has covered some of Britain's most ambitious self-build projects since the BAFTA-winning programme made its debut in 1999, and he says: "I have lots of favourite projects, and some of them are my favourite because they're people who I have kept in touch with and some of them are my favourite because I adore the building or the place, or simply because we've had a fantastic time there.

"Often it's because there's a really good pub within walking distance which we go to lunch for!"

McCloud describes the making of Grand Designs as "very old-fashioned".

"First of all we turn up with very little in the way of scripts and we film what we see using the energy of the day.

"It doesn't happen very much in TV these days, and our stories are made in the edit because we don't know, three years down the line, how it's going to end.

"The other thing we do is we choose projects we think we're going to love, because there's nothing worse than turning up to something that you don't like.

"You want to be able to get excited about the projects, excited about the ideas.

"Mercifully the world is full of people building houses, putting their souls and passions into them, which we thoroughly respect, and we want to capture that."

Also key to the show's longevity, McCloud insists, are the people.

"Watching one concrete block put on top of another is not interesting.

"I'm a building nerd but I wouldn't ever want to put any of that on camera. It's the people's stories which make it."

With that in mind, the eight episodes of series 18 promise to be as entertaining as ever, with viewers able to follow everything from an ambitious, upside-down, New Zealand-inspired hill house in the Malverns to an innovative space-saving home squeezed into a tiny corner of east London, and a reconstructed old lodge melded to a giant black cube of a house in Haringey, north London.

But while the trials and tribulations - physical, financial and emotional - are a given, the home-builders' ideas are constantly evolving.

"Lots of things have changed," says McCloud. "We've seen underfloor heating, self-cleaning paint and micro-thin double-glazing.

"Lots of tech has come and gone. Whereas at one point people were building massive media rooms in order to drive their electric lighting system or their electrically heated gates, now it's all done from your iPhone, which I like."

McCloud describes the UK's national housing crisis as "really tough".

"It's partly driven, of course, by the fact that we are all susceptible to the idea that if we put money into property it will grow faster than the retail price index, and it's a form of investment."

The businessman set up HAB - Happiness Architectural Beauty - in 2007 to challenge the way "identikit volume housing was built in the UK".

He acknowledges that flitting between that and his TV career requires a lot of labour.

"I'd like to clone myself, if possible. Grand Designs is half of my working life and the other half is the business - and I admit to being something of a workaholic."

The father of four, who has two daughters and two sons with wife Suzanna, admits he enjoys a quieter life these days.

"I really like being in one place. It sounds so dull in this age of 'I've got my bucket list', but I haven't got a bucket.

"I like looking at the ground, I like being in one place and I like the idea of rooting."

Will his children follow in his footsteps? "Well, they're all off doing their own thing," says McCloud, who lives in Somerset. "And all you can ever hope for your kids is that they are happy and that they are fulfilled and they can rise to all the challenges that life brings them.

"I'm getting to the point in life where I'm approaching 60 and that question about future career, 'What's the next big thing?', I realise now that I've got to come to terms, not with where I'm going, but with where I've been.

"I've got to admit that Grand Designs has been the most amazing ride. It's gone around the world to 145 separate countries. It's a tiny thing I've done, but for me it's been enormous, and so rather than what's next - I don't ask myself that question - I just think to myself more of the same, do more, keep going.

"We're nowhere near where we should be in terms of meeting our environmental objectives in terms of sustainability and affordability in the market.

"There's loads more still to do, so I've just got to keep banging that drum and luckily the work itself is so inspiring that it provides all the energy you could possibly hope for."

- Grand Designs is back on Channel 4 Wednesdays, 9pm