After Brasilia's Estadio Nacional hosted seven World Cup matches, architects released a conceptual image of the empty stadium revamped with housing. It's an intriguing sight. Dozens of long, colorful boxes stack up between the structure's pillars — all homes, each 1,130 square feet, inserted into the stadium's extra space.

The image is part of "Casa Futebol," a project from architects Sylvain Macaux and Axel de Stampa and their "spontaneous architecture" agency 1week1project (1W1P). "Casa Futebol" reimagines the 2014 World Cup's 12 stadiums, four of which are expected to sit abandoned as white elephants. The project uses conceptual design as a hypothetical solution for abject poverty and housing deficits in Brazil — major sources of tension surrounding the sporting event.

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Since the images were published on July 6, "Casa Futebol" has received a lot of media attention, lauded as ambitious. But these types of projects are frustrating, despite their good intentions.

How productive is it to create these conceptual designs that, ultimately, amount to nothing physically? At what point do we turn innovative thought into action?

Macaux and de Stampa call their projects "thought experiments" — "rough and primarily feeling-generated," Macaux tells Mashable — but some media outlets covered them as if they're concrete plans, only to reveal at the very end of the articles that they won't likely be pursued.

"We consider [1W1P] like a think tank. No matter what the space [is], whether it be urban, rural or digital, there is always something new to offer ... 1W1P identifies a site, puts a diagnosis forward and makes a proposal that will involve an architectural project. There is one rule only: to propose spontaneous and open projects," Macaux says.

Graduates of the illustrious École Nationale Supérieure d'Architecture de Paris-Belleville, Macaux and de Stampa have quit their respective jobs in order to run 1W1P. To make a living, they're currently freelancing in France and Chile, where people contract them "to participate [in] architectural competitions, mostly ... But we [also] do architectural office work," Macaux says. "Spontaneous architecture" has allowed them to come up with digital designs in short amounts of time, though nothing has actually been built. They're looking to make 1W1P their first concrete job.

They take feasibility into account, but it isn't their primary concern. Macaux admits each concept is something they're "playing with," and some of their projects are more realistic than others. "Casa Futebol," he believes, achieves a balance "between realism and utopia."

1W1P's conceptual image of housing incorporated into Arena das Dunas in Natal, Brazil.

When I ask Sheila Kennedy, principal at Boston-based Kennedy & Violich Architecture, Ltd. and architecture professor at MIT, about the practicality of "Casa Futebol," she says it's unclear because it only presents a series of static images.

"Ideas in design are not the same as images. To evaluate feasibility, one would need information on access — how you get to the units, elevators — and what the social idea of the community is and what the concept for sustainable climate control is in Brazil," she says.

Macaux says that with the right team, the project would "surely work" (though, issues with size, space and fire safety certainly don't seem to work in his favor). But in this case, he and de Stampa were more interested in the problem than the solution.

"We wanted to bring people to question ... the future of those gigantic installations and about the social contexts that always accompany those programs," Macaux says.

Their approach is somewhat refreshing — focusing on the underlying problem (poverty) rather than the superficial problem (an empty stadium). It's also certainly a better goal than a prisoner processing center, which one judge proposed.

If we limited our imaginations to the physical world — sticking only to what already exists — there would be no innovation. And innovation begins with exactly what Macaux says: questioning the future.

But my frustrations aren't so much with creating these concepts; they're in failing to pursue real solutions.

Reimagining defunct sports stadiums is old hat. We face the issue around the world on rotation: The Summer and Winter Olympics alternate every two years, and the World Cup occurs every four. Extremely expensive stadiums are raised only to be neglected later (the four white elephants in Brazil cost $2 billion; all 12 cost nearly $4 billion in total spending).

The physical detritus, economic waste and social impact are things we've unfortunately come to expect with these large-scale sporting events.

In order to build all World Cup facilities, Brazil forcibly displaced thousands of people. One Brazil-based architect estimated 250,000 people were evicted; others cite 170,000. The evictions took place amid severe housing deficits in various cities, with an estimated 1.8 million people living on the street.

In São Paulo, the biggest city in South America, close to one-third of the city's 11 million residents live in favelas. The nearby Arena de São Paulo cost an estimated $1.2 billion BRL (approximately $530 million USD) for the World Cup — nearly 1.5 times the projected price tag.

While the Brazilian housing crisis has gradually improved overall, there are still many challenges — rents and property prices, for example, continue to soar. And according to the CIA's Gini index, which measures inequality, Brazil remains the 16th worst country for distribution of income. "Cup for the rich, scraps for the poor" was a common chant among World Cup protests.

And Brazil isn't even the most extreme case — China evicted 1.25 million people for the 2008 Beijing Summer Olympics. The country spent $40 billion on its stadiums; many continue to deteriorate as empty shells. Other Olympic stadiums, such as Sarajevo (1984 Winter Olympics) and Athens (2004 Summer Olympics), are either abandoned or rarely used. Only two of South Africa's 2010 World Cup stadiums are financially sustainable.

Weeds sprout in the remains of what was once the playing field at the abandoned Olympic softball venue in southern Athens, Thursday, Aug. 2, 2012. Years after the 2004 Olympic Games, many of the venues remain abandoned or rarely used. Image: Thanassis Stavrakis/Associated Press

In Brazil's defense, the 2014 World Cup's stadiums were the latest in sustainable design. The government also partnered with the United Nations Environment Programme for various projects during the event, including green certification of stadiums, organic food production and sustainable tourism programs.

But the aftermath of these events is what planners should focus on most. London attempted to solve this issue by building some temporary, portable structures for the 2012 Olympics, including its basketball arena (pictured below).

Why aren't we pursuing the means and the technology to make that widespread practice?

The London 2012 Olympics Basketball Arena was one of the largest temporary venues ever built for any Olympic Games. Image: Flickr Brian Harrington Spier, 8DCPhotography

Sustainably revamping a large sports structure is certainly possible, Kennedy says, whether it's through planning for post-use before construction, or after construction through retrofit.

But, especially when it comes to housing, strategic design questions must be considered, including how community forms in a given area and how the design will benefit that area's residents.

"The stadium is brutal and strong as a figure, but I don’t think the retrofit or housing needs to be subservient in the design. The identity response to concrete brutalist stadiums might take housing in some entirely new directions," she says.

A "thought experiment" can be useful in showing how many billions of dollars go into creating temporarily used structures, especially in cities and countries where people can't even get something to eat. But, especially in Brazil's case, this was all known to the masses during construction — years before the event even took place. Now that the Cup is over, it's more or less an afterthought to the rest of the world.

Brazil is poised to host the Olympics in Rio in 2016, and we'll be faced with the same issues — building pricey structures without regard for the nation's underclass, only to have those structures fall into disuse. (However, the Olympics will reuse four of the World Cup arenas, and the CEO of Rio 2016 claims everything will be kept on time and on budget — though, construction is already behind.)

In Brazil, the solution is in planning and construction — facing this issue head-on before these structures are built. Kennedy believes Brazil has many opportunities, not so much with singular buildings, as have been featured in the media, but with the "buying power, political voice and aspirations of an emergent middle class ... The first thing I would try to do is look at local materials and building traditions and differentiate the responses in the different stadiums," she says.

It's especially timely for Russia and Qatar to consider all this, as they will host the 2018 and 2022 World Cups, respectively. But, like in Brazil, human rights abuses are an even bigger issue than sustainability. In Qatar, some laborers say they have not been paid in more than a year, and their living conditions are allegedly appalling. There's also international concern over the rising toll of construction-related deaths (70 laborers have died from falls or strikes by objects, 144 in traffic accidents and 56 have committed suicide). An ESPN investigative documentary estimates that, at the current rate, more than 4,000 workers will die by the time the 2022 World Cup occurs.

I propose we continue making sustainable, socially aware concept designs, like 1W1P has set out to do, but let's do so with intent on making them a reality. The general public, as well as FIFA, need to put pressure on these host countries, and work with them. When it comes to design, imagination and progress should inform each other.

"Over the past few years, there’s been a relinquishing of the architectural imagination. It's become fashionable on the Internet to accept the frame and turn architecture into 'infill' that may or may not be informally organized," Kennedy says.

"We have to reclaim the architectural imagination. Why should we accept the modern concrete frame at all?"