Regular readers may remember French "guerrilla architect" Stéphane Malka for his parasitic shelter, and his new work, Plug-in City 75, is similarly unconventional. The novel project will renovate an aging Paris apartment building by attaching wooden boxes to the facade, increasing living space for the residents and improving the building's energy-efficiency.

Located in Paris' 16th arrondissement, a stone's throw from the Seine, the interior of the 1975-era apartment building in question currently looks gloomy and cramped, says Malka.

While the city's building codes prohibit extending the building upward, extending it outward isn't an issue, so the architect designed multiple prefabricated wooden boxes of varying size to increase living space and improve conditions for the residents.

The lightweight boxes will be prefabricated in a workshop from sustainably-sourced wood – presumably treated to increase durability – and mounted directly to the building's facade.

Each occupant has the choice of what they want to use the new space for, such as a lounge, for example, and balconies and loggias will also be installed. The facade will be covered in greenery, too.

According to Malka, the addition of the new extensions will improve the aging building's energy performance. Indeed, the press release indicates a very impressive reduction from around 190 kWh per m2 per year down to 45 kWh/m2/year.

Malka Architecture told us that Plug-in City 75 should be completed by mid-2018.

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