After being commissioned to create an extension for a Victorian-era terrace in London, MATA Architects conceived a neat method of providing fine control over the amount of light inside and the privacy available. The firm installed a complex prefabricated shutter system that's controlled by hand crank.

"Situated on a dense urban site with neighboring buildings in close proximity, any proposed extension would be overlooked from multiple sides – a typical London situation," explains MATA Architects. "At the same time, driven by a desire to maximize natural daylight provision and celebrate key views across adjacent gardens, we wanted the new space to benefit from large windows. We asked ourselves, can we introduce large glazing whilst regulating levels of shading, natural daylight, privacy, and security at different times of the day?"

Named the Black Box, the extension was prefabricated in Scotland then shipped to the site, which previously hosted an old conservatory. From there, it took a week to install. It's clad in dark stained Siberian Larch and is topped by a green roof (not pictured).

Inside, the owners use a couple of hand cranks that are connected to a system of winches that in turn manipulate the shutters to get the desired amount of daylight. The space is usually used as a home office but the firm also added a small bathroom for when it's used as a guest bedroom.

It takes six rotations to fully open or close the shutters and the winch mechanisms are self-locking, allowing the shutters to be left open at any point. When fully open, they overhang to offer shade during summer.

Black Box was completed earlier this year and also involved Entuitive and Old School Fabrications. Check out the video below to see it in use.

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