When Olaf Janssen and his wife were searching for a plot on which to build their house, they found one in the Dutch city of Delft that was the right price. Never mind that it was a plot of water.

Janssen worked with a team of experts to design, construct and engineer his two-story, three-bedroom floating home — with basement offices with underwater windows that look out into the water and a terrace — atop a pond.

“We have a spectacular view,” he said. “And we don’t have to worry about garden maintenance.”

Janssen found the experience of building and living on water so positive that in July he launched a company specialising in the construction of floating houses called Balance d'eau.

In recent years more floating developments, both individual properties such as Janssen’s home and larger communities, have sprung up around the world. That’s led some development experts to say on-the-water communities could be a more sustainable, affordable and, in many cases, safer, option than building on land.

The Netherlands includes a substantial amount of water, and that is in fact where many pioneering water-based property developments have been concentrated. The 75-building community, Waterbuurt, within the IJ Lake in east Amsterdam’s IJburg community, made waves around the world for being the first development of its kind: a large-scale, planned development of what could be considered conventional homes—not house boats. It exists entirely on the water with floating multi-story, glassed-in family homes that are interconnected with floating sidewalks.

The movement to the water, however, is happening along coasts around the world. London mayor Boris Johnson has already selected a developer to build Britain’s first floating village at London’s Royal Docks. Other water-based developments, both residential and commercial, are being considered or are in the works in places including Boston, Sydney, Helsinki and the Maldives.

Demand

Both desire and need are driving demand.

The majority of the world’s metropolises are located along the water. More people than ever live in urban areas and all numbers point to that migration trend continuing, according to the United Nations’ World Urbanization Prospects 2014 report. As a result, city populations are becoming denser and land and property scarcer.

At the same time, sea levels are rising. This challenge from Mother Nature becomes ever more apparent and real with each natural disaster, such as when Superstorm Sandy flooded swaths of downtown New York City in 2012. Rather than try to fight the water, as the Dutch have historically done with dikes, for example, some people are deciding to work with it.

“At a global scale, floating urban expansion almost seems inevitable,” said Bart Roeffen, creative director of DeltaSync, a Rotterdam-based firm that focuses on floating urban development and provides research, design and consultancy services to domestic and international clients. 

Changing tides

Until recently, living on the water had largely been perceived as an alternative lifestyle. That was the perception Janssen had before an affordable plot and some research changed his mind.

“In the past, floating houses were shaped like a cigars, had very low ceilings and were stuck upon each other in the city canals,” he said. “Now it is possible to have the same comfort as a normal house on the land.”

And progressive engineers and architects are starting to make more people realise the potential water holds.

“Water is real estate,” said Mathias Tobias of Vancouver-based International Marine Floatation Systems (IMFS), a company that since the 1980s has been building floating properties for international clients. “It previously hasn’t been thought of that way, but it really is. It happens to be 71% of the real estate on earth. And that’s an eye-opening kind of thought.”

Constructing the custom homes isn’t more expensive — and in some cases costs less — than a home in a popular city. Janssen notes that his homes cost about 1,500 euros ($1,944) per square metre, with the lot, architecture and some construction costs not included. In Paris, a flat could cost over 6,600 euros ($9,018) per square metre. A 2,400 square foot home on a 1,200 square foot float foundation would cost about CAD$702,000 ($640,015) from IMFS. Prices range from about CAD$150 ($134) per square foot to CAD$600 ($547) per square foot, Tobias said.

Of course, waterfront property is always among the most coveted, fetching high prices for even a sliver of a view out to the horizon. But actually living on the water can give people pause. Families with small children might worry about the dangers of drowning, for one.  

When DGVGROUP, a Dutch sustainable architectural and development firm with offices in the Netherlands, China and Turkey, conducted research in the Netherlands in 2012 related to floating properties, people indicated they felt safer living on land than on the water.

“Even though it’s safer to live at a floating village, people still wanted to live behind the dikes with their feet on the ground,” said Ron de Gruyter, CEO of DGVGROUP.

While it might seem counterintuitive to build on the ever-changing water, experts insist, as de Gruyter does, that it’s actually the safest place to be when it comes to natural disasters such as floods and earthquakes. When done right, floating properties are engineered and designed to be dynamic, according to Tobias. When the waters rise from flooding, the home also rises. Earthquakes also pose little threat, as the home can move with water, unlike a grounded building engineered to only shift so much.

Furthermore, floating developments can do double-duty to protect the land along their coasts from flooding by acting as a buffer, say experts.

Developing or investing in floating property also attracts sustainability advocates. Such projects can be constructed from top-to-bottom with the environment in mind, from the materials used to the potential to harness the power of the water.

“Because the development on water is not connected to the grid, all the innovations from water management, energy production and energy reuse and so on can be implemented,” said Karina Czapiewska, director of project development at DeltaSync.

Logistical challenges 

The largely unprecedented nature of such projects raises infrastructure and logistical challenges.

For example, while Janssen could purchase a water plot in Delft, most of the world’s water is publicly owned or not owned at all. Such avant-garde projects could require a new approach to real estate transactions. Space on the water might need to be leased, as it is in a boat marina.

“The key to floating development is support,” Roeffen said. That includes buy-in from local government — which can mean policy changes or clarification of laws, regulations and codes.

In Boston, architecture firm Perkins+Will is in discussions with the city for approval of a floating village along the Charles River. The multi-family housing project Floatyard is in the "very early stages," according to Robert Brown, managing director of Perkins+Will's Boston office, but there has been both interest from the city's side and a development entity, as well as excitement about the design. 

While the city already has a community of residents who live on their boats year-round, the city has nothing like the proposed multi-story residential complex, said Nancy Kueny, associate director of sales at Gibson Sotheby's International Realty in Boston.

“It’s not for everyone,” she said. “But I think there would be a huge amount of interest because of its novelty and the forward-thinking technology.” The development is likely to attract the same kind of people who are drawn to unique properties such as converted warehouses, she said.

Still, there will be some adjustments. Parking presents a conundrum, and there are other smaller matters to bear in mind, too.

“Don’t drop your keys when opening the front door,” Janssen said. “They could fall in the water.”

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