Presenter discovered some viewers downed shots at regular occurrences on show and wrote episode to get them drunk

Grand Designs host Kevin McCloud made an episode of the architecture show “deliberately designed to get people as drunk as possible” after discovering its fans had invented a drinking game based on it.

The long-running Channel 4 show follows families designing and building their dream homes, and the rules of the game mean viewers have a drink when regular occurrences happen on screen, including the owners running out of money or quitting their job to manage the project.

McCloud said: “We even actually wrote an entire programme around the drinking, and it’s covert so one of the programmes is deliberately designed to get people as drunk as possible.

“There are all kinds of rules, like every time I used the word ‘bespoke’ it’s a double shot, the wife gets pregnant half way through, that’s a treble”.

Other rules include having a drink if the owners ignore planning permission or the windows do not fit.

McCloud, who has been presenting the show for more than 15 years, was awarded an MBE last year.

He set up his own lighting design firm and appeared on BBC makeover show Home Front before launching Grand Designs, which he writes and presents. It has led to a spin-off magazine, books and a live show.

He is currently filming a new show for Channel 4 about people who have chosen to live in isolation from the modern world.