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More Trees


TSUMIKI are simple triangle-shaped wooden blocks named after Japanese building blocks tsumiki. The blocks have a variety of uses – from being used for play by children and adults, much like the Danish building blocks Lego, to being produced in larger sizes to build architectural structures like the TSUMIKI pavilion by Kengo Kuma in Tokyo Mid-Town Park (2014-2015). The countless ways in which the blocks can be stacked is limited only by the imagination.

TSUMIKI are designed by architect Kengo Kuma, based on a commission by More Trees, a forestry conservation organization led by renowned Japanese musician Ryuichi Sakamoto. Enquire about TSUMIKI kit in The Shop at Japan House London.

About the product

The smooth triangle-shaped TSUMIKI are made from FSC (Forest Stewardship Council) certified cedar wood from Morotsuka Village in Miyazaki Prefecture, Japan where one of More Trees' Forest locates. The notch at the tip of each piece allows the blocks to be fitted together easily to create structures. They are available in sets of 7, 13 or 22 pieces and range from 4cm wide to nearly 13cm high. TSUMIKI will stimulate creative intelligence in both adults & children.

About the designer

Kengo Kuma is a world-renowned contemporary architect whose portfolio includes the recently-opened V&A Dundee and Tokyo 2020 National Olympic Stadium. In 1990 Kuma established Kengo Kuma & Associates, and he is currently Professor at the Graduate School of Architecture, The University of Tokyo.

Tsumiki, building blocks, played an important part in Kuma's childhood and his development as an architect. According to him, one of the purposes of TSUMIKI is to stimulate creative intelligence in children.

About More Trees

More Trees was launched in 2007 by five founders, including Oscar-winning musician Ryuichi Sakamoto. Their goal was to connect cities and forests and to ensure "a society where forests and people co-exist for generations to come". The organization engages in collaborative work with local communities for conserving forests, planning and developing ways to encourage use of domestic timber, and sharing information and promoting forestry conservation at seminars and events. One of their conservation efforts includes the eco-friendly technique of tree thinning, which allows forests to continue to thrive. It is from thinned wood that products, such as TSUMIKI, are created.