Here's a breakdown of the kinds of windows used in different countries. The striking thing is the high proportion of aluminium windows used in Japan. You may remember that aluminium has a thermal conductivity around a thousand times bigger than wood or PVC. In fact it would be difficult to find a material for window frames which would conduct more heat, and each time I see them, I shake my head in disbelief. As you can see from the chart, living in Japan I do a lot of head-shaking.
For those reading in black and white, the charts are for (West to East) France, UK, Germany, Scandinavia, Korea, Japan, US. (No mention of India, China or Russia.) As for the colours, pink is aluminium, Yellow is wood, light blue is compound (for example aluminium with insulation), turquoise is PVC, which the site is promoting, showing in the table how Germany, the US and trendy neighbour South Korea use PVC in 60, 67 and a whopping 80% of their windows, while poor Japan only uses 7%. The red circle proclaims PVC is the global standard.
Looking more closely, for the Japan pie chart, yellow is marked aluminum compound, and wooden windows appear to be as unusual here as aluminium is in Scandinavia. And you thought wood was a traditional building material in Japan! I just checked the source data, where wooden windows make up less than 0.1%, so the data may in fact be completely ignoring wooden windows.
So why is this happening? Not so much the lack of wood or scarcity of PVC, but why so many aluminium windows?
Just a hypothesis, but what if the Japanese window manufacturing industry were controlled by the aluminium industry? The number one objective of the Japanese aluminium industry is to increase the use of aluminium. This is not surprising, and may not be sinister, unless you consider the prevalence of growth economics as an evil threat to our survival on the planet, which I for one do.
Protecting the environment is also an objective of the Japan Aluminium Association, so there may be a conflict of interest. For example, using aluminium in window frames will increase the use of aluminium. Using PVC or wood will reduce heating costs and be good for the environment. Increasing the use of aluminium is higher on the list of priorities, so we'd better do that!
If this hypothesis were true we would see the largest window manufacturers in Japan belonging to the Aluminium industry.
They may be better known around the world for the other part of their business, zips and zippers, where they have a massive global market share, but YKK also have a substantial architectural parts business, and make most of the window frames in Japan. YKK do belong to the Japan Aluminium Association.
However, if you look for YKK windows in English, you'll find information like this on their US plant, making and supplying vinyl windows. Not a mention of aluminium. Their Japanese website talks about the new windows they are making, with insulated aluminium frames. They don't seem to mention PVC frames for the domestic market. The mission statement and their fancy environment report talk about sustainability and energy efficiency, but when it comes to details, there's more emphasis on double glazing and low-e glass, but the care still aluminium. So more thermal bridges leading to condensation and while the aluminium frames aren't going to rot or rust, the wooden frames of the building they are fitted into may. Rather than replacing the windows, people will need to replace the building! So there is a different story for the English-speaking market, where "PVC is the standard" and domestic Japan, where there may still be some people who think that aluminium is a wonderful new product, and it's certainly seen as a normal way of fitting bits of glass into the walls of your wooden house.
Looking through the main shareholders of YKK, which is not listed on the stock exchange, there is no obvious link between YKK and the rest of the aluminium industry, and perhaps aluminium frames are just used because they are cheaper, and considered a normal part of a Japanese house. Momentum keeps the world turning. In some cases it keeps us hurling towards the abyss.
Or perhaps it is the power and inertia of YKK's president, Tadahiro Yoshida, son of the founder, who turned around the window business that was inherited from his uncle, and perhaps has the same view of windows as he did when he started managing the company in the 1970s.
The invention of the Sony Walkman is one example of how the strong ideas of a company leader can steer the company, but here is another about YKK, that I read on Forbes.com. I don't usually read Forbes magazine but it came up in one of my searches. Tadao Yoshida, founder and father, once announced that "golf will ruin Japan". He probably just meant that too much focus on playing golf would mean companies wasting money and Japan possibly taking its eye off the ball of business, but this lead to golf fans within the company keeping their habits a secret, until after Tadahiro, the son, had taken over and he announced one day that he was off to play golf. At this point the golfers could reveal their habit once again and many came out of the closet.
So who knows why aluminium is so prominent in Japanese windows, but the only way to change it is to raise awareness among consumers, and more importantly architects and builders, that there is an option.
Note: It was difficult to find precise information on the Japanese window industry. Although YKK seems to be the biggest producer, they do not mention "market share" once in their annual report. I kept getting google hits for a report on the global window and door market, but they were charging for it. It would be nice if information on windows were more transparent.
Acknowledgement: The world window map is from Excel Shanon who seem to be making the best windows in Japan at the moment, although I think they are still somewhat limited by the thickness of glass that will fit in the standard frame size, so their triple glazed windows may not perform much worse if the middle glass layer were removed and they become double glazed.
For those reading in black and white, the charts are for (West to East) France, UK, Germany, Scandinavia, Korea, Japan, US. (No mention of India, China or Russia.) As for the colours, pink is aluminium, Yellow is wood, light blue is compound (for example aluminium with insulation), turquoise is PVC, which the site is promoting, showing in the table how Germany, the US and trendy neighbour South Korea use PVC in 60, 67 and a whopping 80% of their windows, while poor Japan only uses 7%. The red circle proclaims PVC is the global standard.
Looking more closely, for the Japan pie chart, yellow is marked aluminum compound, and wooden windows appear to be as unusual here as aluminium is in Scandinavia. And you thought wood was a traditional building material in Japan! I just checked the source data, where wooden windows make up less than 0.1%, so the data may in fact be completely ignoring wooden windows.
So why is this happening? Not so much the lack of wood or scarcity of PVC, but why so many aluminium windows?
Just a hypothesis, but what if the Japanese window manufacturing industry were controlled by the aluminium industry? The number one objective of the Japanese aluminium industry is to increase the use of aluminium. This is not surprising, and may not be sinister, unless you consider the prevalence of growth economics as an evil threat to our survival on the planet, which I for one do.
Protecting the environment is also an objective of the Japan Aluminium Association, so there may be a conflict of interest. For example, using aluminium in window frames will increase the use of aluminium. Using PVC or wood will reduce heating costs and be good for the environment. Increasing the use of aluminium is higher on the list of priorities, so we'd better do that!
If this hypothesis were true we would see the largest window manufacturers in Japan belonging to the Aluminium industry.
They may be better known around the world for the other part of their business, zips and zippers, where they have a massive global market share, but YKK also have a substantial architectural parts business, and make most of the window frames in Japan. YKK do belong to the Japan Aluminium Association.
However, if you look for YKK windows in English, you'll find information like this on their US plant, making and supplying vinyl windows. Not a mention of aluminium. Their Japanese website talks about the new windows they are making, with insulated aluminium frames. They don't seem to mention PVC frames for the domestic market. The mission statement and their fancy environment report talk about sustainability and energy efficiency, but when it comes to details, there's more emphasis on double glazing and low-e glass, but the care still aluminium. So more thermal bridges leading to condensation and while the aluminium frames aren't going to rot or rust, the wooden frames of the building they are fitted into may. Rather than replacing the windows, people will need to replace the building! So there is a different story for the English-speaking market, where "PVC is the standard" and domestic Japan, where there may still be some people who think that aluminium is a wonderful new product, and it's certainly seen as a normal way of fitting bits of glass into the walls of your wooden house.
Looking through the main shareholders of YKK, which is not listed on the stock exchange, there is no obvious link between YKK and the rest of the aluminium industry, and perhaps aluminium frames are just used because they are cheaper, and considered a normal part of a Japanese house. Momentum keeps the world turning. In some cases it keeps us hurling towards the abyss.
Or perhaps it is the power and inertia of YKK's president, Tadahiro Yoshida, son of the founder, who turned around the window business that was inherited from his uncle, and perhaps has the same view of windows as he did when he started managing the company in the 1970s.
The invention of the Sony Walkman is one example of how the strong ideas of a company leader can steer the company, but here is another about YKK, that I read on Forbes.com. I don't usually read Forbes magazine but it came up in one of my searches. Tadao Yoshida, founder and father, once announced that "golf will ruin Japan". He probably just meant that too much focus on playing golf would mean companies wasting money and Japan possibly taking its eye off the ball of business, but this lead to golf fans within the company keeping their habits a secret, until after Tadahiro, the son, had taken over and he announced one day that he was off to play golf. At this point the golfers could reveal their habit once again and many came out of the closet.
So who knows why aluminium is so prominent in Japanese windows, but the only way to change it is to raise awareness among consumers, and more importantly architects and builders, that there is an option.
Note: It was difficult to find precise information on the Japanese window industry. Although YKK seems to be the biggest producer, they do not mention "market share" once in their annual report. I kept getting google hits for a report on the global window and door market, but they were charging for it. It would be nice if information on windows were more transparent.
Acknowledgement: The world window map is from Excel Shanon who seem to be making the best windows in Japan at the moment, although I think they are still somewhat limited by the thickness of glass that will fit in the standard frame size, so their triple glazed windows may not perform much worse if the middle glass layer were removed and they become double glazed.
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