Optical Glass House by
Hiroshi Nakamura & NAP

| 33 comments

A tree-filled courtyard is glimpsed through the shimmering glass-brick facade of this house in Hiroshima, designed by Japanese architect Hiroshi Nakamura (+ movie).

Optical Glass House by Hiroshi Nakamura

Optical Glass House was constructed beside a busy road, so Hiroshi Nakamura and his studio NAP wanted to create a private oasis where residents could still make out the movements of people and traffic beyond the walls. "The serene soundless scenery of the passing cars and trams imparts richness to life in the house," said the architect.

Optical Glass House by Hiroshi Nakamura

The garden is raised up to first floor level to make room for a garage below and the architects used 6,000 specially made glass blocks to build a two-storey-high wall in front of it. The wall was too tall to support itself, so the blocks had to be bolted together.

Optical Glass House by Hiroshi Nakamura

As light filters through the glass it creates dancing patterns across the walls and over a group of maple, ash and holly trees.

Optical Glass House by Hiroshi Nakamura

"The facade appears like a waterfall flowing downward, scattering light and filling the air with freshness," said the architect.

Optical Glass House by Hiroshi Nakamura

An open living room is located just behind and is only separated from the garden by a lightweight metal curtain. This curtain folds back to reveal a second glass-block wall at the back of the room, which lines the edge of a central staircase.

Optical Glass House by Hiroshi Nakamura

Residents are faced with the staircase upon first entering the house. A water basin skylight is positioned immediately above and projects more light patterns onto the floor.

Optical Glass House by Hiroshi Nakamura

A split-level second garden is located at the back of the house, while the children's rooms occupy the top floor, a dining room and kitchen are on the first floor and a hobby room, Japanese room and extra bedroom can be found on the ground floor.

Optical Glass House by Hiroshi Nakamura

Hiroshi Nakamura worked under Kengo Kuma before setting up his studio in 2002. Previous projects include the Roku Museum, a small art gallery with softly curving walls.

Optical Glass House by Hiroshi Nakamura

See more architecture in Japan, including a house fronted by a stack of gardens.

Optical Glass House by Hiroshi Nakamura

Photography is by Koji Fujii, Nacasa & Partners.

Optical Glass House by Hiroshi Nakamura

Here's some information from the architects:


Optical Glass House

This house is sited among tall buildings in downtown Hiroshima, overlooking a street with many passing cars and trams. To obtain privacy and tranquility in these surroundings, we placed a garden and optical glass façade on the street side of the house. The garden is visible from all rooms, and the serene soundless scenery of the passing cars and trams imparts richness to life in the house.

Optical Glass House by Hiroshi Nakamura

Sunlight from the east, refracting through the glass, creates beautiful light patterns. Rain striking the water-basin skylight manifests water patterns on the entrance floor. Filtered light through the garden trees flickers on the living room floor, and a super lightweight curtain of sputter-coated metal dances in the wind. Although located downtown in a city, the house enables residents to enjoy the changing light and city moods, as the day passes, and live in awareness of the changing seasons.

Optical Glass House by Hiroshi Nakamura

Optical Glass Façade

A façade of some 6,000 pure-glass blocks (50mm x 235mm x 50mm) was employed. The pure-glass blocks, with their large mass-per-unit area, effectively shut out sound and enable the creation of an open, clearly articulated garden that admits the city scenery. To realize such a façade, glass casting was employed to produce glass of extremely high transparency from borosilicate, the raw material for optical glass. The casting process was exceedingly difficult, for it required both slow cooling to remove residual stress from within the glass, and high dimensional accuracy. Even then, however, the glass retained micro-level surface asperities, but we actively welcomed this effect, for it would produce unexpected optical illusions in the interior space.

Optical Glass House by Hiroshi Nakamura

Waterfall

So large was the 8.6m x 8.6m façade, it could not stand independently if constructed by laying rows of glass blocks a mere 50mm deep. We therefore punctured the glass blocks with holes and strung them on 75 stainless steel bolts suspended from the beam above the façade. Such a structure would be vulnerable to lateral stress, however, so along with the glass blocks, we also strung on stainless steel flat bars (40mm x 4mm) at 10 centimeter intervals. The flat bar is seated within the 50mm-thick glass block to render it invisible, and thus a uniform 6mm sealing joint between the glass blocks was achieved. The result - a transparent façade when seen from either the garden or the street. The façade appears like a waterfall flowing downward, scattering light and filling the air with freshness.

Optical Glass House by Hiroshi Nakamura

The glass block façade weighs around 13 tons. The supporting beam, if constructed of concrete, would therefore be of massive size. Employing steel frame reinforced concrete, we pre-tensioned the steel beam and gave it an upward camber. Then, after giving it the load of the façade, we cast concrete around the beam and, in this way, minimized its size.

Optical Glass House by Hiroshi Nakamura

Project name: Optical Glass House
Main purpose: Housing
Design: Hiroshi Nakamura & NAP Co.,Ltd.
Structure design: Yasushi Moribe
Contractor: Imai Corporation
Location: Naka-ku, Hiroshima-shi, Hitroshima, Japan
Site area: 243.73m2
Total Floor area: 363.51m2
Completion year: October,2012
Structure: R.C.structure

Optical Glass House by Hiroshi Nakamura

Above: site plan

Optical Glass House by Hiroshi Nakamura

Above: ground floor plan

Optical Glass House by Hiroshi Nakamura

Above: first floor plan

Optical Glass House by Hiroshi Nakamura

Above: second floor plan

Optical Glass House by Hiroshi Nakamura

Above: section

  • mik

    One of the best Japanese house I’ve ever seen. Beautiful. Congrats.

  • pluk

    Does it looks nice? Yes. Is it worth the costs and the technical complications? I doubt.

    • Pablo

      Whether is it worth it or not is something quite personal. There’s a say in engineering that asks “what do you want and how much are you willing to pay for it?”

  • bonsaiman

    Beautiful, beautiful, beautiful! I really envy the owners. Congrats to the architects.

  • Manuel

    Incredible and absolutely stunning. Something of the best I’ve seen for a while!

  • kering

    Astonishing.

  • arianadourre

    Wow. Just beautiful.

  • zina

    Very impressive!. Very good architecture. But after looking at the context plan, facing a main street with heavy traffic is making me doubting that the courtyard is not as peaceful as it looks in the pics.

  • g.w.

    What a very nice atmosphere! Beautiful!

  • Peter Scorer

    So peaceful and serene that it’s almost like a modern morgue. And that robot moving around the house looks like a real human being.

    Seriously now, how would they replace the glass wall if damaged by an earthquake? Is it really noiseless inside?

    • staff

      It is amazingly quiet and peaceful!

    • d.b

      Solution: build a bunker (anti-atomic). Oh, end of the world…

  • Mayavi

    It’s certainly beautiful, but then in a country like Japan known for its scarcity of space, this is a huge chunk probably occupied by a couple or a nuclear family.

    It somehow seems unfair to the ones living in a pigeon hole of an apartment and paying a fortune in rent. This should actually be treated as an art installation and not living quarters.

    • bonsaiman

      Let me introduce you: the rich.

      • Maya

        Thank you.

    • 675887678

      Communist idiot.

      • Shane

        Capitalist fool.

  • Gdane

    I’ll take two please.

  • Will

    A new look at Maison de Verre by Pierre Chareau – nice but not as good as the original.

    • Will

      On second thoughts it is really very good, and most importantly, honest.

  • http://lettuceoffice.com nico

    Literally took my breath away. That courtyard is incredible.

  • Ted

    Home, I love you, but I think I’ve fallen in love with another house!

  • Angela

    The special thing about this house is that I would like to be in it, not necessarily an idea that comes to my mind with all “interesting” architecture!

  • jkl;sdaf

    It looks amazing. Only what where they thinking with the design of the bathroom? The marble doesn’t fit in with the rest of the interior at all.

  • CHR

    Genius! Love the front garden and glass wall.

  • http://www.walnutgreydesign.com/ Mr Walnut Grey

    Like an incredible mirage.

  • Pablo

    It´s just brilliant.

  • http://eugenelubomir.com Eugene

    Absolutely fantastic material effects!

  • Jun

    So far, this is the best house I have seen on this website. Nice!

  • Ber

    Astonishing. And I love the fact that we all agree! Bellissima!

  • Pablo

    Beautiful home, plain and beautiful. One can clearly see Kengo Kuma’s influence on the glass facade and the intention of taking the glass material to its limits in order to dematerialise it.

  • d.teil

    A remarkable concept for the Japanese market, but at least not for the european market. It’s just dark inside as the movie shows. And I will not believe that it will be quite as the movie likes to show us.

  • ishwindar Singh

    One of the best home designs I have ever come across, period. Brilliant work.