Yes, you've locked the door: What drives your checking habit?

Most of us have suddenly thought, “Wait — did I actually lock the door?” For some people, this might lead to locking up with more intention next time. But for others, it may be an anxiety disorder. Researchers say it’s all about being afraid of losing control.

I once had a neighbor who checked the door of his flat a dozen times before leaving for work and walked round and round his car as many times when he arrived back home, to make completely sure that everything was right.

I often imagined the terror he must live with all the time, going through imaginary scenarios of break-ins or the car ignition being left on.

This particular case may have been an instance of obsessive-compulsive disorder (OCD), which is a type of anxiety disorder characterized by an uncontrollable checking behavior and recurring, bothersome thoughts.

However, many of us are exposed to sudden bursts of uncertainty. Did we switch off the gas before leaving for our holiday? Worse still, did we leave one of the children behind?

Absent-mindedness and the rush of getting to wherever we need to go can result in these lapses of memory and the sudden shock when we realize that we’re not sure if we did everything we should have.

New research from Concordia University in Montreal, Canada, has suggested that such a fear of losing control can result in recurrent checking behavior. This, say the researchers, may be at the core of many anxiety disorders, including OCD.

“We’ve shown that people who believe they’re going to lose control are significantly more likely to exhibit checking behavior with greater frequency,” says study co-author Adam Radomsky.

The scientists hope that the new findings allow them to find better ways of treating OCD and other anxiety disorders at their core.

“[W]hen we treat OCD in the clinic,” Radomsky explains, “we can try to reduce [the patients’] beliefs about losing control and that should reduce their symptoms.” The researchers’ findings were recently published in the Journal of Obsessive-Compulsive and Related Disorders.

Lose your fear of losing control

Radomsky and paper co-author Jean-Philippe Gagné, a Ph.D. student, worked with 133 participants recruited from among the undergraduate student cohort.

“[Those] who participated were given bogus [electroencephalograms],” which is a method that is designed to measure electrical activity in the brain, Radomsky explains. “They were randomly assigned false feedback that they were either at low or high risk of losing control over their thoughts and actions,” he adds.

Once they had convinced the students that they were either in complete control or at risk of losing control, the scientists asked them to complete a computer task that required them “to control the pace of pictures” by making them disappear before they faded from the screen on their own.

What the participants weren’t made aware of, however, was that they had no actual control over the images, which were programmed to float in and out of sight at specific paces.

The participants were instructed to use various key combinations to control the images, and press the space bar to confirm their command.

Radomsky and Gagné found that the participants who were convinced that they were at higher risk of losing control of their actions engaged in more meticulous checking behavior than their counterparts, who were told that they were likely to maintain control.

‘Potential to improve’ anxiety therapy

What the team found most surprising was that none of the study participants identified as having OCD. This, the scientists think, is an indication that a fear of losing control stands at the core of many anxiety disorder symptoms.

The findings verified the researchers’ initial working hypothesis, “[T]hat people’s fears and beliefs about losing control may put them at risk for a range of problems, including panic disorder, social phobia, OCD, post-traumatic stress disorder, generalized anxiety disorder, and others.”

Knowing that at the bottom of excessive checking behavior lies the worry of losing control over the situation may pave the way to more appropriate cognitive behavioral therapy for the treatment of a range of anxiety disorders, the researchers say.

Source: Medical News Today

Air conditioning: the benefits, problems and alternatives

Amid record-breaking heat, increased access to air conditioning could save lives – but AC units are damaging the environment. Are there other options?

Much of the Earth sweltered under record-topping temperatures this month. Phoenix, Arizona, broke its record for most 110F (43.3C) days. California’s Death Valley had its highest temperature ever. An airport in coastal Iran saw a heat index of 152F, while Beijing saw a record stretch of 95F days.

Oppressive heatwaves have become more frequent and more severe as a result of the climate crisis – a trend that’s expected to continue, and could worsen in proportion to how quickly we can transition from fossil fuels.

To beat the heat, people are increasingly turning to air conditioning. The number of AC units globally could increase by 244% by 2050, according to the International Energy Agency, and demand could rise by 59% within the US, according to a 2020 analysis by independent research group Climate Central.

Increased access to air conditioning could save lives; after all, in the US, extreme heat is the single deadliest form of extreme weather. But it could also come with drawbacks.

Below we look at the challenges today and in the years ahead, and consider some of the alternatives.

Billions of people don’t have access, and the energy costs are huge

The technology can be expensive to purchase and run, often rendering it inaccessible to poor communities in the US and globally. In the US, research shows lower-income households are much more likely to lack access to the technologies. And one 2019 study found that between 1.8 and 4.1 billion people in developing countries who regularly experience dangerously high temperatures lack access to cooling technology.

“In much of the world, in many countries, we’re concerned that people who most need air conditioning don’t have it,” said said Narasimha Rao, a professor of energy systems at Yale University who co-authored the paper.

AC usage also puts pressure on electricity grids. That can be risky: if a five-day heat wave and a power outage hit the city of Phoenix at the same time, more than 50% of the city’s current population of 1.4 million could end up in the emergency room, one recent study found.

Many are working to make air conditioners more affordable and to improve the reliability of electricity grids. Yet there is another problem: air conditioners warm the Earth.

The appliances use a lot of energy. Between now and 2050, cooling technologies including AC units are projected to be the biggest contributor to growing energy demand, according to the Intergovernmental Energy Agency – a problem, since most global energy currently comes from fossil fuels. The US broke its summer record for daily gas consumption on at least two separate occasions, data from S&P Global Commodity Insights shows, and AC usage is a key contributor.

Most AC models also require the use of planet-heating chemicals to cool the air. The most commonly used refrigerants in ACs are hydrofluorocarbons (HFCs) are potent greenhouse gases – thousands of times more effective at trapping heat than carbon dioxide.

Some air conditioners do use the more climate-friendly refrigerants hydrofluoroolefins (HFOs), though these can still create ecological damage. Other alternatives include ammonia and propane, but both can be harmful to humans when they leak.

Companies are now also using newer kinds of refrigerants, like R-32, which is an HFC that is half as planet-warming as older ones traditionally used for air conditioning.

And experts say that by employing other strategies to lower temperatures in homes, we can lessen the environmental toll of air conditioning, allowing people to stay cool without warming the planet.

There are more energy-saving cooling technologies

One of the buzziest air conditioning technologies are electric heat pumps, which can both heat and cool homes. On hot days, the appliances pump hot air out of the home and draw cool air in.

These technologies are far more energy efficient than traditional air conditioners. They also require far less refrigerant to work.

Traditional ACs and heat pumps both cool homes by directly lowering air temperature and also by pulling moisture out of the air, which can make a home more comfortable. But combining the two processes makes the appliances “terribly inefficient”, said Les Norford, professor of building technology in the Department of Architecture at MIT.

Norford and others are working to develop new technologies that separate the two functions to boost efficiency. Some models use living membranes or physical desiccants – materials that suck up humidity – instead of energy-powered processes to pull moisture from the air.

Improving the energy efficiency of air conditioners is crucial. According to the International Energy Agency, in 2018, the average air was less than half as efficient as the best available technology. And the least efficient models – often found in low-income households – require even more power to run, rendering them both more climate-warming and expensive.

More options for cooling

Other common technologies can play a major role in cooling homes. Fans, for instance, are much cheaper and far less energy consuming than ACs, said Rao, the Yale professor. They can also be surprisingly effective, especially in hot, dry environments.

“In some cases they can provide up to 2C of relief,” he said.

Rao is also studying the potential for dehumidifiers to be used as a widespread cooling technology, as they can also greatly improve comfort in hot and muggy areas.

“In Mumbai, where I’m from, you can have tremendous relief from drying the air,” he said. “In my house it’s pretty hot and humid, but I go to the basement which has no air conditioning, just dehumidification, and it’s still so much cooler.”

In hot and dry heat, another useful low-energy technology is the air cooler, also known as the swamp cooler. These devices use a fan to recirculate air across a cool, wet material and then disperse the freshly dampened, cool air into the home. Like dehumidifiers and fans, swamp coolers are cost and energy efficient, and are also widely available.

But there are low-tech ways to keep homes cool, too

Buildings can be better designed to keep temperatures down.

One crucial strategy is weatherization, said Vivek Shandas, a geography professor at Portland State University who studies the impacts of climate change in urban areas.

“We’re often throwing AC at homes – especially older homes, homes where lower-income communities of color live – without doing any weatherization like insulating or sealing up the cracks the windows and the doors where that outside extreme heat can come in,” he said. As a result, residents can end up being forced to crank the ACs to their highest settings to keep indoor temperatures down.

Weatherization, said Shandas, would reduce the amount of AC required to maintain a comfortable setting, resulting in lower energy bills and greenhouse gas emissions.

Some homes are also built with highly heat-absorbing materials. Residents of mobile homes and trailers, which are often made with steel or aluminum, are often most vulnerable to extreme heat, said Shandas.

In south Asia and other parts of the global south, said Rao, metal roofs – often found on slums – are common because they are inexpensive.

“An aluminum sheet for a roof is the worst thing you can do from a heat perspective,” he said.

But some materials used to make homes, such as brick and stone, can absorb and release heat more slowly. Improving the availability and affordability of such materials could save lives in the extreme heat.

Homes – especially roofs – can also be painted white to lower indoor temperatures. White roofs products stay coolest under the sun’s rays because they reflecting away between 60 and 90% of sunlight, according to the Department of Energy. And buildings can be designed with ventilation in mind to lower temperatures. Wind towers, for instance, can be built to draw cool breeze indoors; placing ponds of water underneath them can make the structures even more effective.

What about shade?

Shade can make a big difference within the home and outside of it. The simple act of drawing opaque curtains closed, for instance, can help push down indoor temperatures, said Shandas. Communities can employ that same strategy by planting trees throughout neighborhoods.

“We know that treed neighborhoods can be up to 15 degrees cooler than ones with no trees,” said Shandas.

Trees and other plant life can also be installed on rooftops to help insulate buildings from hot air outside. These strategies are especially useful in urban “heat islands” where abundant concrete draws in thermal energy – areas which are disproportionately occupied by low-income people of color, Shandas added.

Can we get rid of AC?

Experts say a world eliminating AC would be dangerous.

“There are some parts of the world where really, you cannot do without air conditioning, where you have really muggy weather throughout the year,” said Rao.

But strategically using other methods to cool down communities could cut costs and emissions. It could also cut down on a knock-on effect of air conditioning: in highly dense areas, running them can raise outdoor temperatures by 1C (1.8F).

Different strategies will work best in different contexts, said Shandas. And in some cases, several should be applied at once.

“We are not in a position as a species to necessarily think that we are going to be able to find that silver bullet out of this extreme heat,” said Shandas. “We need to be finding the myriad different effective solutions that are socially and politically palatable, and that are sustainable in the long run.”

Source: The Guardian

How Big is a House? Average House Size by Country – 2023

Redefining “Enough Space” – Average House Size Around The World

How big is your house? Is it big enough? Is there an optimum house square footage of space per person? This post takes a look at the average house size around the world and asks how much space is enough.

The New York Times published a piece about Graham Hill’s 420 square-foot (39 square-metre) apartment in which he argued that having less space and less stuff can create room in your life for more important things (remarkably this figure is close to Hong Kong and India’s average house size).

From a carbon emissions point of view you got the feeling that his travel habit probably negated much of the benefits of having less stuff. But that aside it raised an interesting question: how much square footage is enough space for a house? Below we compiled figures from different statistical sources that include CommSec, RBA, UN, US Census, European Housing 2002, European Housing 2002, Australian Bureau of Statistics, Canadian Home Builders Association, Infometrics, and the Japan Statistical Yearbook.

A few caveats. First, one caveat is that many of the figures are from surveys of self-reported house sizes. This means figures could be unreliable due to the way people report numbers. Second, almost certainly we are mixing apartments and free-standing dwellings. Third, there will no doubt be great regional variation within a country for example the US is a huge country with differences from state-to-state. Nevertheless this is reasonable as a picture using a broad brush stroke. We also cover the contributors to the carbon footprint of a house here if you’re interested.

Average House Size By Country

If you asked all the people of the world whether they would prefer a bigger or smaller house I’d guess almost everyone would plump for more square footage. That makes perfect sense for people living in small and overcrowded spaces, but is there a point at which we have enough space?

To get a little perspective I’ve put together a graphic to illustrate how big the average new home is around the world. The figures are in square footage of usable floor space, and include data for both houses and flats.

Average house size for 15 countries around the world: smallest is 484 square feet in Hong Kong and largest is 2303 square feet in Australia

In the countries I could get data for the average new home varied in size from 45 m2 (484 ft2) in Hong Kong up to 214 m2 (2,303 ft2) in Australia.

The average house size in the US was 225 m2 (2426 ft2) in 2017. The average house size in the UK is relatively small at 76 m2 (818 ft2) while the average house size in Canada is quite big at 181 m2 (1,948 ft2). For China the data only reflects urban properties, which now average 60 m2 (646 ft2) and have almost doubled in size in the last 15 years.

The same information, updated with new sources of information is given in this table below, conveniently given house sizes in different countries using both square feet and converted to equivalent square meters as a measure of the house area.

Average House Size In Different Countries

Average US House Size Has Been Increasing Over Last 50 Years

In the US, the average house size has been increasing since the 1970s. The peak was actually in 2015 at 2467 sq ft (229 sq meters) and then it dropped slightly over the next two years. Here we show a chart of the trend over time up to 2017. New data from 2021 indicate that things haven’t changed much – the average house size was 2,273 sq ft which still puts it below the 2015 peak.

Still, one thing for sure is that larger houses demand more heating and cooling. Unless increased demands are offset by gains in efficiency or renewable sources, we will see greater carbon emissions from residential energy needs. One thing to note – house sizes change slowly. In a span of 10 years, the average increased from 2250 to 2400 sq ft for the US.

Average US house size peaked in 2015 and dropped slightly afterward. The trend is upwards and there are no indications overtime house sizes won’t increase.

There are other ways to mitigate both heating and cooling demands. These include better insulation, and better heating and cooling technology.

Average House Square Footage Of Floor Space Per Person

There are all sorts of reasons for these differences. Wealth levels, urbanization rates, land access and climate all play a part. Nonetheless the scale of the differences is pretty fascinating. The thing that is really missing from this picture is people. We can take our analysis a little further by looking at how much floor space this equates to per person.

Using data on average household size we can estimate floor space per inhabitant for new homes. This analysis is a bit rough and ready, as it assumes new homes are being built for the average household. Nonetheless it is useful because it helps to control for the considerable differences in household size between countries.

Here are the figures in square-meters.

Average residential floor space in square meters

At just 15 m2 (161 ft2) a person in Hong Kong has just a quarter of the floor space of the average Australian or American.

The Graham Hill House Is Not So Remarkable In Certain Countries

If Graham Hill lives by himself then his trendy 39 m2 (420 ft2) is similar to someone from Sweden. In fact in the range from 30-45 m2 (323-484 ft2) are the averages for Italy, the UK, Japan, Spain, Sweden, France and Greece.

At our place we have 110 m2(1,184 ft2) for a family of four, which is 27 m2 (291 ft2) per person. Having previously lived in a few different flats of 50-60 m2 as a couple this feels pretty palatial, and is certainly more than enough for us. But 30 m2 per person is much more generous in a four person family than it is in a studio apartment for one.

London’s Minimum Space Standard

In London they have a new minimum space standard as part of the London Plan. For new flats the minimum standards are 37 m2 (398 ft2)for one person, 50 m2 (538 ft2) for two people in one bedroom, 61 m2 (657 ft2) for three people with two bedrooms, 70 m2 (753 ft2) for four people in two bedrooms and 74 m2 (797 ft2) for four people in three bedrooms. Are these enough space?

In my mind if you have decent ceiling heights, good windows, clever storage and not too much stuff a little space can go a long way.

Smaller Houses Take Less Energy To Build And Keep Habitable

A smaller home requires less embodied energy to build, has lower heating and cooling needs, needs fewer furnishings, takes less time to maintain and requires less work to fund.

In terms of carbon emissions small is beautiful. But how small is too small?

How much space do you think is enough?

Source: Shrink that fooprint