The embarrassing mistake Kevin McCloud says too many of us make when renovating

Can you believe that Grand Designs has now been on our screens for 20 years? There can't be too many things that host Kevin McCloud hasn't seen in the course of presenting the show, overseeing some quite amazing projects, from water tower conversions to houses built from shipping containers.

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Those two decades of experience also mean that Kevin is well versed in the dos and don'ts of renovating. And there's one thing that's increasingly bothering him.

Speaking to The Times, Kevin revealed that he's rather tired of people's bathroom habits... or rather, their habit of including way too many bathrooms when planning a build.

'Bathrooms are extremely wasteful in terms of resource, yet people are putting more in their homes than there are actual occupants,' he says. 'Four people live in the house and put in six toilets. I don’t understand that.'

'You can’t use more than one at a time and, frankly, you only need to use it four or five times a day,' he adds.

'Estate agents have always sold houses by the number of bedrooms; soon they’ll do it by the number of WCs.'

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A 2017 study by insurers Direct Line found that to make a home more desirable to buyers, it should have two bathrooms for every three bedrooms. That means – according to 70 per cent of the estate agents asked – any four-bed house should have 2.6 bathrooms and a five-bedroom property would have 3.5 bathrooms.

The agents were also asked to estimate how much value a bathroom would add. Nationwide, they predicted that an extra bathroom would add 6.8 per cent to the value of a three-bedroom house, which, factoring in average house prices, would be around the £12,000 mark.

However, the estate agents surveyed also suggested adding a bathroom might not be the best way to add value. In fact, 91 per cent agreed that converting or extending to create a bedroom would be a better bet.

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'With space in such short supply in homes across the country and the cost of moving sky high, it is interesting to find out directly from the experts what homeowners can do to add value to their property,' says Rebecca Clapham, head of household products at Direct Line.

'A new bathroom can add around £12,000 to the value of a home, which compared to the cost of fitting one, is a significant return. So it may be a good option for people wishing to improve their home but without the space to add an extra bedroom or improve their kitchen.'