Dutch studio Doepel Strijkers has unveiled designs for a sunken pavilion with earth walls and a rooftop greenhouse, which will be built in Almere ahead of the Floriade 2022 horticultural expo (+ slideshow).
The base of the building will be sunken down five metres below sea level, while the roof will function as an elevated winter garden.
Inside, the structure will house an innovation workshop centred around the themes of nutrition, health and wellbeing.
"The high ambition of this sustainable and innovative construction sets the tone for other developments on the Floriade 2022 site," said Doepel Strijkers, whose other projects include a proposal for a huge inhabitable wind turbine in Rotterdam.
During the expo, the building will serve as the pavilion for Flevoland, a Dutch province established in the 1980s on land reclaimed from the Zuiderzee inland sea. The majority of the province sits five metres below sea level, hence the floor level of the pavilion.
Exposed walls below sea level will be clad in mirrors to create the illusion that the upper section is floating.
By contrast, the upper walls and roof will be constructed from earth with visible strata lines. A greenhouse will be located in the centre of the roof, surrounded by a grass garden.
"The design embodies the story of the 'making of' Flevoland," said the design team. "Innovative water management, sustainable energy and food production form part of its DNA."
"The building makes optimum use of the microclimate with natural shading, passive heating and cooling and natural ventilation," it continued.
"The massive earth roof is optimally used to create a comfortable indoor climate all year round. The climate greenhouse with a transparent glass solar chimney on the roof is a winter garden and regulates the natural ventilation."
MVRDV's design for a new peninsula over the Almere lake was pivotal to the city's winning bid to host the next edition of the Floriade garden festival, which is held in the Netherlands every 10 years.
As well as hosting the six-month festival, it will provide a new city quarter containing a university, offices, homes, hotels and leisure facilities.
The peninsula is still under construction, although the SubZero Pavilion could be open for use by students and start-ups by early 2017. The development team expect it to "buzzing with activity" all the way up to the Floriade launch.
"In doing so, it is not only innovative in 2016 but also in 2022," added Doepel Strijkers.
Located on the outskirts of Amsterdam, the city of Almere is just 40 years old and was also built on land reclaimed from the sea. Other recent projects in the city include a wave-shaped viewing platform and a pair of matching homes for a brother and sister.