Tucked away on a suburban housing estate in Sheffield is a house built with the sole purpose of answering these questions. Developer David Wilson Homes has built a 3,500sq ft, detached four-storey stone house with five bedrooms and four bathrooms, and installed a family in it to test-drive the future. It may look very traditional from the outside, but inside it has every gadget the developers could think of.

At the end of May, Nick Parnell, his wife, Sue, and their two teenage daughters, Lucy, 16, and Hazel, 13, arrived for a six-month free holiday in this luxury house, christened Project:LIFE. The only price to pay is that they must wear electronic wrist tags that tell a computer in the house where they are and which electrical appliances they use. The information will be analysed by the University of Nottingham’s school of the built environment. Energy use is being monitored and all the family’s rubbish examined.

Chosen from 70 families who applied, the Parnells actually live just around the corner on the same estate, in a more traditional four-bed house bought two years ago for £325,000. They got the job because they’re comfortable with the high-tech appliances — Nick, 42, is is an information technology (IT) specialist, designing call-centre systems, and Sue, also 42, is an IT teacher — and because they have children old enough to form and voice their own opinions.

In nearly every room, computers can connect wirelessly to printers and the internet, which adds between £5,000 and £10,000 to the cost of a house. How much the family use this facility will help determine whether it is worth adding wireless systems to other new-build houses.

There are very big, self- cleaning windows, which, David Wilson Homes says, cost little more to build than solid walls, plus underfloor heating. It’s more energy- efficient than radiators but adds thousands to the cost of a house and takes longer to fit.

In addition, there are luxuries such as a £7,000 shower, an £8,000 hot tub and £700 cooking hob — visitors are impressed by the sunken bath in the Parnells’ en-suite (with plasma television) — but are they wow factors that will shift a house?

The Parnells have already answered one of the developer’s questions, because they love the underfloor heating. Sue says: “I’ve been back to our own home to decorate, and radiators are the bane of my life. Not to have them would be fantastic. In our own kitchen the tiled floor feels very, very cold, whereas here it’s heaven to walk on.” For her, underfloor heating, in the kitchens and bathrooms at least, is now a must-have.

Having experienced the drenching effect of a proper power shower, the Parnells plan to rip out and replace their own — only two years old — when they return home in November.

Wireless technology and the ability to pipe music or radio into any room is another definite selling point for them. “We asked about this when we bought our house, but it wasn’t available,” says Nick. “Now it would cost about £3,000 a room to have it installed, which we wouldn’t pay.”

The big windows are also a hit. “When we bought our house we thought it was light, but now when we go back to it, it seems dark,” says Sue.

With the government insisting on denser housing, David Wilson Homes also wants to find out if digging down to build basements will be a solution. To test this idea, the firm spent £50,000 buying a prefabricated concrete basement and digging it into Project:LIFE’s rocky soil. The developer wants to know if it might prove popular enough elsewhere to warrant the extra construction cost — which would be lower on easier ground.

The Parnells are expecting their wrist tags to show it was worth the money to excavate. The basement den, laid out as a small sitting room with a plasma-screen television — which is where the girls camped out to watch the Glastonbury festival at high volume — also has a laundry, complete with a low-tech but very popular laundry chute, and storeroom. Nick’s favourite basement gadget? “The automatic shirt-ironer.”

Another experiment is the house’s staggered levels, to add character. Walking through the kitchen and eating area, four steps lead down into a large, high-ceilinged living room. It’s a hit with the Parnells.

Nick says: “Nearly everybody under 60 loves this house, but older people don’t like all the stairs; nor do people with small children.”

Open-plan living is one of the biggest changes of the 21st century. But how many walls do we want knocked down? The Parnells admit that if their daughters are in the living room watching a film on television, it can intrude into the kitchen/eating area.

Sue says: “When Hazel had six friends in the living room, I had to escape to the den. With open-plan houses, you have got to have escape zones.”

Ideas from Project:LIFE are already changing drawing- board plans at David Wilson Homes. The company wants the basement idea to succeed because many of its homes are built on brownfield sites, where the developer has to dig down anyway to clear any contamination.

Paul Slater, the firm’s technical director, says: “We’re looking at houses that have a kitchen/dining area in the basement with a lightwell, a bridge over this at street level to reach the door, then a living room and study on the upper ground, with bedrooms and bathrooms on the first and second floors.”

Some of these ideas will be incorporated in one-bed houses that will be marketed across the country next spring for less than £100,000. They’ll mimic, for example, Project:LIFE’s high-ceilinged rooms by putting the bedroom downstairs and using a vaulted ceiling, rising as far up as the rafters will allow, in the upstairs living room.

When the Parnells go back to reality in November, the Project:LIFE house will go on sale, possibly for £1m, according to agents who have toured it. Three potential buyers have already said they’re interested. Two identical houses are planned for Leeds.

For Nick, it’s way beyond his purse. But if he had the money, would he buy it?

“If it were £800,000, I’d think about it,” he says, “but for £1m, I’d like some grounds — this property has only a small garden.”

www.projectlife.info

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