With spring around the corner, we face a perennial dilemma: when to turn off the central heating.
Crocuses and daffodils may be starting to show, but with the aftermath of Storm Doris, torrential rain and temperatures stubbornly refusing to budge above the decidedly chilly, many prefer to remain cocooned in our artificially warmed offices and homes for a good few weeks at the very least while the rest get decidedly hot under the collar at the prospect.
For the cranking up of the thermostat is guaranteed to spark a debate like no other; while the chilly-blooded welcome the warmth, the warm-blooded feel stifled by it.
It’s something on which few of us can agree.
In 2015, a survey of office workers in the US revealed that 42% of employees think their work environment is too warm, 56% too cold. Sound familiar?
Professor Mike Tipton, a researcher in the extreme environments laboratory at the University of Portsmouth says the subject of central heating causes more arguments at work and at home than any other.
“As humans, we are hugely sensitive to thermal change, but there are also individual differences that determine how we respond to a drop or rise in warmth.”
Under Irish legislation, no maximum temperature for a workplace is prescribed and the recommendations that it must be ‘comfortable’ and ‘ventilated’ are somewhat vague.
A minimum 16C to 17.5C is recommended by the HSE for the desk-bound, but the requirements are not compulsory and neither are they necessarily going to keep everyone happy.
A review of evidence by the US-based Berkley National Laboratory concluded that the ‘ideal’ office temperature is around 21C to 22C and scientists, intrigued by the discrepancies in what they term ‘thermal comfort’ have shown that some of us are unable to tolerate a drop of even a few degrees in the workplace without suffering.
More often than not, there’s a gender divide with women maintaining they are still freezing into popsicles at this time of year, while men have started wearing t-shirts.
What makes our tolerance levels to temperature changes so markedly different?
In his own studies, Professor Tipton has shown how it’s the temperature of our body’s extremities that drives our perception of how uncomfortable hot or cold we feel and women, more prone to icy hands and feet, experience the cold sooner than men.
This is partly down to hormones.
“There’s evidence that the female hormone oestrogen is involved in up-regulating the system that shuts down blood vessels and slows blood flow to the hands and feet,” Tipton says.
“This female physiology explains why they are often the first to feel chilly.”
What’s more, researchers from Maastricht University reporting in the journal Nature, suggested that the average office thermostat is set according to the needs of middle-aged men and based on “a thermal comfort model that was developed in the 1960s”.
It’s based on a formula that is derived using the resting metabolic rate (how fast the body generates heat) of a 40-year-old man weighing 11 stone.
Women, with their smaller body size and proportionately higher levels of body fat, usually have slower metabolic rates and, suggested the Maastricht team, probably need their offices 3C warmer to remain in their comfort zone.
Beyond comfort, does it make a difference if we overheat or freeze at work or home?
Some studies have found that productivity in tasks like typing predictably take a nose dive when you feel cold — one showed that work output halved and error rate more than doubled among a group of female typists when room temperature was lowered from 25 to 20 degrees — and yet a slightly cool environment has been shown to keep employees more alert.
An ambient temperature has been shown to promote creative thinking, but if it’s too hot (above 27 degrees) it limits our ability to perform cognitive and mathematical tasks.
Overly cosy environments can also see waistlines expanding.
A study three years ago, again by the temperature experts at Maastricht University, showed how heating our homes and offices mean our bodies no longer need to burn extra calories to keep warm.
They suggested 19C is sufficient to provide the right metabolic balance, but that people should “try turning the thermostat down” or “go outside” as often as they can.
Being too warm might also affect immunity. In 2015, researchers at the University of Aberdeen suggested that the “eternal summer” provided by electric lighting and central heating is confusing winter seasonal genes that work to fire up immunity.
Humans evolved to respond to seasonal variations in temperature, but heating homes to a comfortable temperature all year round means the genes no longer switch on in the same way to fight off infections like colds and flu.
Ultimately, though, experts say there is no right or wrong room temperature. Your upper limit is likely your colleague’s lowest ebb.
“A constant temperature, with no sudden changes, is more important than the absolute temperature at work,” Tipton says.
“We can learn to live with small variations and they have less impact than you might think.”
Let the cold wars continue.
If you feel the cold, then paying extra attention to your hands and feet could be the answer.
Your toes and fingers numb in response to blood vessels constricting to prevent heat loss which is why scientists at the University of California have developed cutting- edge, foot-warming devices, heated by a light bulb and placed discretely beneath a desk, for office use.
“Our foot warmers use only 160 watts maximum, and 20 watts on average during working hours,” says Professor Edward Arens, director of the centre for environmental design and leader of the research.
“This is much lower than the poorly designed 1000W electric ‘fires’ on the market, which do not save much money or any energy.”
He says that warming the feet and wrists effectively means a room temperature can be lowered by around 2C, reducing a building’s total heating and cooling requirement by 20%.”
The team has also developed heated shoe insoles.
“Traditional insoles will help but they are inherently bulky,” Arens says.
“Our electrically heated insole should fit in conventional shoes, and be powered by a magnetic field transmitted from a floor mat.
“It’s pretty hi-tech for doing a simple task like keeping your feet warm, but once developed it could actually be an exceptionally efficient and economical way to make buildings more comfortable and energy efficient.”
As yet, none of Arens’s inventions is available commercially. Watch this space.