Grand Designs: Princess Diana's divorce lawyer’s unfinished home has a £1,500 cat flap

Kevin McCloud demonstrates how £1,500 cat flap works - sparking reaction from viewers

Watch Kevin McCloud demonstrate how £1,500 Passivhaus compliant cat flap works

What did you miss?

Engineer Duncan and Liz, a divorce lawyer to the stars including Princess Diana, are still building their revolutionary home in the Cotswolds which appeared on Grand Designs - but it does have a Passivhaus compliant £1,500 cat flap installed.

The couple have set their hearts on building Passivhaus Premium powerhouse - “Passivhaus” means the home must be airtight and energy efficient, for it to be “Premium” it must generate four times the energy it uses.

No one has built a Passivhaus Premium home before in the UK.

After years of fighting with the planners to adapt the design, the pair got stuck into building with a budget of £1.2million but unfortunately it remained unfinished three years on when Kevin McCloud went back to see their progress.

Kevin McCloud shows how the £1,500 cat flap in Grand Designs home works.
Kevin McCloud shows how the £1,500 cat flap in Grand Designs home works (Channel 4)

How, what and why?

While it is unfinished, the Grand Designs presenter McCloud marvels at the home when he visits the site.

One of the elements of their home which takes the interest of the star's interest is the £1,500 cat flap - and it immediately gets the attention of viewers at home too.

The presenter can’t resist testing out and showing the audience how it works before revealing the staggering cost to have it fitted.

Unlike a standard cat flap, this one works to ensure the Passivhaus home remains sealed and McCloud lifted the lid on how it worked.

Grand Designs latest energy efficient home in North Cotswolds
The huge home in North Cotswolds remains unfinished on Grand Designs (Channel 4)

He said: "This is a pet friendly Passivhaus house compliant cat flap. Cat comes along and comes up to the cat flap.

"It's got seals and everything. It’s completely air tight. Then it shuts and the building is sealed again. Ooh, and it’s got a special device so it doesn’t chop the cat in half!"

In the voice over, McCloud revealed that a Passivhaus compliant cat flap costs around £1,500 to fit into a home.

"At around a grand and a half, it had better work because the Passivhaus assessor is here," McCloud said.

Kevin McCloud joining Liz and Duncan at Grand Designs house (Channel 4)
Engineer Duncan and divorce lawyer to the stars Liz are still building their revolutionary home in the Cotswolds (Channel 4)

The assessor concluded the house passed the Passivhaus Premium test - but it has one more assessment to go.

"It's an epic result," McCloud congratulated the homeowners.

Social media was sent into meltdown over the cost of the cat flap, with one writing: "£1,500 spent on a cat flap? I don’t think so."

Among the sea of comments, others wrote: "Man on Grand Designs has spent GBP 1,000+ on a cat flap. Cat’s never gonna f***ing use that, babe."

"Why would you spend £1.5k on a cat flap, instead of bringing mice into the house as a gift the cat better start bringing wallets into the home instead."

Grand Designs' north Cotswolds home (Channel 4)
The couple were building a huge home for the two of them to live in (Channel 4)

"Expensive cat flap but still only seen the dog."

"1500 quid for a cat flap?! Idiots."

"£1500 on a cat flap, when we all know that the cat will sit waiting for one of them to open the door for it."

"£1500 for a cat flap, it’s time to stop and have a long hard look at your life."

Grand Designs home in North Cotswolds (Channel 4)
It was the third home this series to remain unfinished (Channel 4)

"Passivhaus cat flap for 1500 quid."

"Is the cat even alive after all this time?"

"Yeah, cos a cat is deffo gonna use that."

"Eco cat flap, give over."

"The cats can have a wing to themselves by the look of it."

What else happened on Grand Designs?

Grand Designs: The living room space in their North Cotswolds home  (Channel 4)
The living room space in their North Cotswolds home (Channel 4)

Introducing the couple, McCloud revealed Liz is a divorce lawyer with some notoriety as she has worked with some of the stars.

Her previous clients have included Diana, the Princess of Wales and Bernie Ecclestone’s wife Slavica.

Liz has no qualms being honest about how people perceive her while she's doing her job.

She said: "I’ve been referred to as the terrier, the poisonous dwarf, the gnome from hell, if someone has been rude about me I’m doing my job."

At the end of the episode, engineer Duncan revealed it should take another 18 months to finish the build - and Liz shared her hopes this would come true.

As the house wasn't complete once again, making it the third unfinished home in the series, viewers took to social media to complain about the series.

"Rename Grand Designs to Unfinished Project," one wrote, among the comments.

Others added: "A bad day and then another unfinished Grand Designs project put the seal on it. At least the next revisit where the woman was rude to Kevin should be worth watching."

"Stop showing us unfinished houses! There have been three unfinished Grand Designs ina. row now - the most unsatisfying thing ever."

North Cotswolds - Grand Designs. (Channel 4)
There were a few spaces in the house which were completed (Channel 4)

"The houses of the future will all be unfinished and over budget?"

"Great - an airtight, unfinished, vast, empty shed. But airtight."

"Why would you buy a barbecue set for an unfinished house?"

"I'm not sure I like this trend of unfinished-ness on Grand Designs."

"A whole series of unfinished homes - so frustrating Grand Designs."

"Grand Designs more like unfinished designs."

"Grand Designs does feel like it's becoming an absolute cluster flat of unfinished buildings by people who always have more money than they say but less long term sense to actually finish a project. An eco house of size? Not the first and no wonder another seems to be faltering."

"Do they just want to do revisits now with all these unfinished houses?"

Read more: Grand Designs