Next up in our 21st-Century Architecture: 25 Years 25 Buildings series, we take a look at the most significant building of 2005, Moriyama House in Japan by architect Ryue Nishizawa.For those unfamiliar, Moriyama House can be quite quickly summarised by artist Henk Visch's experience of it in 2007, when he visited to create sculptures for its owner, Yasuo Moriyama."When visiting Mr Moriyama's house to find a spot for my sculptures, I could hardly describe where I was," Visch recalled."This was no normal house. Where was the front door?" he asked.Ryue Nishizawa's Moriyama House was the most significant building of 2005Nestled on a compact plot in the dense neighbourhood of Kamata in Tokyo, Moriyama House is a network of minimalist, non-hierarchical blocks stitched together with tiny gardens.Its design by Japanese architect Ryue Nishizawa the co-founder of Pritzker Architecture Prize-winner SANAA rewrote all the typical rules of privacy, thresholds and density when it comes to housing.Though describing the project as a house, or even a building, feels like a disservice to its design. Labelling it as a miniature city or a microcosm of Tokyo is somewhat more accurate.Moriyama House is made up of ten white blocksMoriyama House is made up of 10 white blocks, ranging in height from one to three storeys and occupying just half of its 290-square-metre plot.The blocks each serve a unique function, requiring residents to step outside as they move between the spaces, just as though they are navigating a mini village.Between them are paths and gardens that link directly to the surrounding streets, free of fencing and leaving the boundary between private and public space ambiguous.Nishizawa's tactic is reminiscent of the layering of ancient Japanese buildings Rob Gregory in The Architectural ReviewThis feeling of openness to the public helps to establish an unusual sense of community at the site, which is enhanced by the placement of large square windows allowing views into the white boxes from all around an unusual feature in a Japanese house, where privacy is usually prioritised."Japanese people often like a fence to enclose the property," Nishizawa once said when discussingthe design."But this project, there's no fence to define the property. Anybody in this area can get in and out."Minimalist white finishes unify the individual buildingsThe fragmented layout mimics the surrounding urban fabric, in which individual homes fill their plot but do not touch the neighbouring structures, leaving small walkways between them.It also reflects Nishizawa's view that "life can't be contained within a single lot"."People's sense of living expands beyond it, effectively erasing all borders," he once said.Read: Herzog & de Meuron's Tate Modern was the most significant building of 2000After visiting the house in 2007, former senior editor at The Architectural Review Rob Gregory said Nishizawa's design is "reminiscent of the layering of ancient Japanese buildings"."This striking group of six dwellings is a demonstration of how traditional notions of privacy and community can be adjusted," Gregory wrote."The Moriyama House has echoes of primitive forms of dwelling, where functions were distributed as isolated units that collectively create a defensible settlement. It also addresses Nishizawa's key concern regarding how to open up the house as a component of the city," he continued."Critical of the fact that many Japanese houses have become too hermetic and opaque, with homes that increasingly turn away from the street to focus on internal courts, Nishizawa's tactic is reminiscent of the layering of ancient Japanese buildings."The blocks each serve a unique functionCurrently, the owner occupies one of the volumes, which contains two bedrooms, a study and a living area. The rest of them are used as rental apartments.Despite their different functions, the blocks are unified by their bright and geometric designs, formed of thin steel sheet panels that lend a bold minimalist look to the site.In tandem with access to greenery and wide open windows that maximise natural light, this deliberate simplicity helps create a sense of expansiveness offering a lesson in how high-quality living space can be provided in high-density areas such as Tokyo.Dutch architect Martin van der Linden of YouTube channel One Minute Architecture hailed it as "a possibility for an alternative density of habitats"."It shows a possibility for an alternative density of habitats in the city as a collection of cell-like architectures or an architecture as the city," he said.Nor does it appear, in the Japanese architectural imagination, that there are any limits to what a dwelling can be Oliver WainwrightJapan is a breeding ground for experimental housing like Moriyama House, largely a symptom of the short lifespan of dwellings there, which averages out at 30 years in Tokyo.This can be pinned to the evolution of housing in Japan in the wake of world war two, and the country's rapid population growth in the 1960s and 1970s that led architects to develop innovative, sometimes wacky, solutions for living in hyperdense metropolises.Today, Moriyama House is arguably the most famous Japanese home in the world and one of the most notable examples of 21st-century Japanese architecture, epitomising the country's experimental and innovative approach to construction.The design rewrites the typical rules of privacy when it comes to housingThough much-loved by architects around the world, it was catapulted further into the spotlight in 2017 when it became a focal point of a landmark exhibition at London's Barbican Centre.The Japanese House Architecture and Life after 1945 centred around a 1:1 mock-up of the home in the gallery's central space. It was co-produced by the Japan Foundation to showcase the changes in Japanese domestic architecture since the end of the second world war.Read: Zaha Hadid's Bergisel Ski Jump was the most significant building of 2002Its curator Florence Ostend selected the house for the main exhibit with the belief that it is "one of the most important houses of the 21st century".In his review of the exhibition, critic Oliver Wainwright shared a similar sentiment, referring to it as "the most startling domestic vision of all"."Visitors will not need to fly to Tokyo to experience the most startling domestic vision of all, thanks to a 1:1 recreation of Ryue Nishizawa's seminal 2005 Moriyama House," he wrote."As Nishizawa puts it: 'life can't be contained within a single lot. People's sense of living expands beyond it, effectively erasing all borders.' Nor does it appear, in the Japanese architectural imagination, that there are any limits to what a dwelling can be."Did we get it right? Was Moriyama House by Ryue Nishizawa the most significant building completed in 2005? Let us know in the comments. We will be running a poll once all 25 buildings are revealed to determine the most significant building of the 21st century so far.This article is part of Dezeen's 21st-Century Architecture: 25 Years 25 Buildings series, which looks at the most significant architecture of the 21st century so far. For the series, we have selected the most influential building from each of the first 25 years of the century.The illustration is by Jack Bedford and the photography is by Edmund Sumner.21st-Century Architecture: 25 Years 25 Buildings2000: Tate Modern by Herzog & de Meuron2001: Gando Primary School by Dibdo Francis Kr2002: Bergisel Ski Jump by Zaha Hadid2003: Walt Disney Concert Hall by Frank Gehry2004: Quinta Monroy by Elemental2005: Moriyama House by Ryue NishizawaThis list will be updated as the series progresses.The post Ryue Nishizawa's Moriyama House was the most significant building of 2005 appeared first on Dezeen.