MultiPly, an eight-meter-high, carbon-neutral, timber pavilion, made exclusively from American tulipwood, has opened to the public in Madrid Rio at its entrance to the Casa de Campo, as part of the Madrid Design Festival. The installation was unveiled on the 1st of February and will remain open for two weeks. A collaboration between Waugh Thistleton Architects, the American Hardwood Export Council (AHEC) and ARUP, MultiPly responds to two of the greatest challenges of our time: the growing need for housing and the urgency to fight climate change, presenting as a solution the combination of modular systems and sustainable building materials.

“MultiPly is comprised of a maze-like series of interconnected spaces that overlap and intertwine. It has been conceived and constructed to encourage visitors to re-think the way we design and build our homes and cities. The three-dimensional structure is constructed from a flexible system of 12 cross-laminated timber (CLT) modules of American tulipwood with digitally manufactured joints as if it were a piece of furniture ready to assemble. More importantly, the 32 cubic meters of tulipwood used for MultiPly stores the equivalent of 22 tonnes of carbon dioxide and is naturally replaced with new growth in the U.S. forests in less than two minutes,” said Roderick Wiles, AHEC Regional Director.

Because it is composed of modules, the construction can be disassembled and reassembled. It was first shown as a part of the London Design Festival in 2018, in the Sackler Courtyard of the Victoria and Albert Museum, then outside the Building Centre in London with New London Architecture, and then at the Universite deglie Studi di Milano, as part of Interni’s ‘Human Spaces’ exhibition at Milan Design Week 2019. Multiply is currently on display in Madrid for its fourth iteration.

“The main objective of this project is to publicly discuss how environmental challenges can be addressed through innovative and affordable construction,” said Andrew Waugh, co-founder of Waugh Thistleton Architects – a practice that has been at the forefront of engineered timber construction for decades. “We are at a point of crisis in terms of housing and CO2 emissions and we believe that building with a versatile and sustainable material such as tulipwood is an important way to address these problems.”

In 2018, the population of the Eurozone’s fastest-growing major economy, Spain, increased to 47 million – the fastest annual growth since 2009. In order to keep up with population growth in ever-expanding cities, in a way that is not harmful to our planet, it is crucial to utilize new technologies that use sustainable materials. Off-site timber construction, that can provide quick-to-assemble, high-quality housing with low carbon emissions, provides a viable solution.

“MultiPly uses a wood engineering technique known as cross-laminate where boards of one layer are placed perpendicularly to the boards of the next layer and glued to form very strong, rigid and stable panels. CLT has been traditionally manufactured with coniferous wood. However, AHEC and Arup have been experimenting with cross-laminated American tulipwood for a decade, which is a fast-growing abundant hardwood that constitutes 7.7% of the total volume of standing timber in the hardwood forests of North America,” added Wiles.

Research and projects have shown that, by comparing identical weights, CLT tulipwood is stronger than steel and concrete and can be machined with incredibly high precision. This makes it ideal for prefabrication and rapid assembly, reducing construction times by around 30%. Tulipwood is an economical and easy to machine timber and incredibly strong for its weight. The use of tulipwood CLT means that large-scale wooden buildings can be built without the use of concrete or steel. These properties, together with its impressive appearance, make tulipwood a perfect pioneer for innovative wood construction.


“The Madrid Design Festival has built its identity around the theme – Redesigning the World. In its third year, the Festival takes a step further to boost the visibility of this ‘world under redesign’ by adding new ideas, venues and institutions to enrich a dialogue that will stimulate the creation of a design culture, from Madrid for the entire society. MultiPly fits in perfectly with the overall theme of the festival given that it explores a new and more sustainable form of construction that combines an abundantly available carbon negative material, and we hope this inspires how we design and build our houses and cities going forward,” concluded Wiles.