Danish architecture firms Lendager Group and TREDJE NATUR want to prove that building tall doesn’t need to come at the cost of the environment or human comfort.

That’s why the two firms teamed up to design CPH Common House, a proposal for the world’s first upcycled high-rise in the Ørestad area of Copenhagen.Draped in greenery, the stepped building would be built from upcycled materials “to an unprecedented extent” for an estimated 1,174 tons of carbon emission savings in the building phase.

Designed to raise the bar for sustainable high-rises in the future, the CPH Common House is a proposal commissioned by SOLSTRA Development – Bellakvarter A/S, but it was not chosen for construction.The conceptual project serves as a springboard for eco-friendly developments in the future.

“With CPH Common House, we propose the world’s first upcycled high-rise building,” the architects explained. “We show how to build high and dense without losing the connection to the history, context and human scale. Strategies on sustainability and circularity are incorporated in the project from the first sketch.”