Keeping Warm in the Deep Freeze
If you grew up in the modern West – North America, for example – you probably grew up with central heating, cheap fuel and a near-endless supply of electricity delivered right to a hole in your wall. Generations of us grew up handling the winter chill with one simple technique: reach for the thermostat and crank it up. This assumption of convenience has shaped how we build houses, how we eat, and how we dress for all seasons. It also means that a fuel crisis or depression – or the winter storm that cut power to half a million North Americans a few weeks ago – can leave us completely vulnerable.
Consider, then, that people lived for thousands of years in wintry lands without a thermostat to crank, or without any modern fuel or technology, and obviously did not all freeze to death – nor were they even necessarily uncomfortable. They built their homes differently than we do, they adopted different dress and habits, and lived with a different set of expectations.Traditional homes in many cultures had thick walls, whose thermal mass absorbed heat during the day and radiated it back during the cool night. Some homes in Ireland, for example, were made of cob – a mixture of sand, clay and straw that could be literally sculpted into a house. I helped built one in County Clare, Ireland, and I’m told it remains cozy inside years later.
Photo: Wikicommons
In many cultures – whether medieval Wales, pre-Columbian America or Ancient Greece – villages were arranged to maximize exposure to sun and light, minimizing the need for burning fuel. Only in recent times have we decided to build without regard to direction or landscape. (1)
“Coupled with other low-tech solutions … passive solar design could all but eliminate the use of fossil fuels and biomass for heating buildings throughout large parts of the world,” wrote Kris De Decker in Low-Tech Magazine. (2)
Of course, many homes used to be easier to heat and insulate, for the simple reason that they were smaller. As recently as 1950, the average new home in the United States was 983 square feet, not much larger than old Irish cottages. By 2004, however, the average had swelled to 2,349 square feet, even though family size had shrunk, and most homes were occupied by just one or a few people. (3)
Realistically, of course, most of us are not going to design new cities or even houses – even if you have an opportunity to build your own home, as we did, budgets and local ordinances might force a compromise with convention. Most people rent or pay a mortgage on an already-built home, and have to retrofit.
Thankfully, retrofitting can go a long way, starting with insulation; according to one organization, 65 percent of American homes have substandard insulation. That wasted energy – whether at the electrical power plant or in the home – has a real human cost; according to a 2003 study, retrofits across the United States would mean 6,500 fewer asthma attacks, and save hundreds of lives and $1.3 billion in health costs. That doesn’t even count the billions we would save in heating costs, the fossil fuels saved for future generations, and the greenhouse gases left un-gassed. (4) (5)
For people who can’t afford new insulation, old clothes stuffed in the attic could also help. Victorians used to insulate inside by putting old wine bottles – empty but re-corked – under the floorboards, creating air pockets. People can simply close off outer rooms and seal them off, keeping heat in areas where people spend most of their time. Trees and vine trellises, moreover, can be positioned to shade homes in the heat and let light through in the bare-branched winter.
You could create your own thermal mass inside your home. A trombe wall is a thermal mass – bricks, black-painted water tanks, anything to absorb heat during the day and radiate it at night. It would usually face the south (if you’re in the Northern Hemisphere), and sit inside your windows – but if you want to build a greenhouse, you could build it on the south side and make your outside wall the thermal mass. (6)
What all these approaches have in common is that they maximize external energy coming into your home (south-facing windows, trombe wall) and keep the heat that’s there from escaping (insulation). All of them, though, involve building or installing something new, and some solutions are even more basic than that – so much so that they are often overlooked. More on that next column.
Footnotes:
(1) A Golden Thread: 2,500 Years of Solar Architecture and Technology by Ken Butti and Jon Perlin, as cited in “The solar envelope: how to heat and cool cities without fossil fuels,” by Kris De Decker, Low-Tech Magazine.
(2) “The solar envelope: how to heat and cool cities without fossil fuels,” by Kris De Decker, Low-Tech Magazine.
(3) “Americans want smaller homes, not McMansions,” USA Today, August 25, 2010.
(4) http://www.naima.org/insulation-knowledge-base/insulation-and-the-environment/energy-efficiency-environmental-savings.html
(5) “The Public Health Benefits of Insulation Retrofits in Existing Housing in the United States,” Jonathan I. Levy, Yurika Nishioka and John D. Spengler, Environmental Health: A Global Access Science Source, April, 2003
(6) The Passive Solar Energy Book by Ed Mazria.
http://www.grit.com/farm-and-garden/do-it-yourself/keeping-warm-in-the-deep-freeze.aspx
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