Keeping the house cool
during the dog days of summer
They did what a lot of people do, they opened all the windows during the night when the temperatures were cooler, and closed them in the morning. Seems simple, right? But they were a little more clever than that. They understood the principles of Thermodynamics- specifically in this case, that hot air is less dense than cold air, and therefore expands and rises, while denser cold air, shrinks in volume and sinks to replace it. This is why hot-air balloons can soar.(You can see more discussion of this in our gliding blog of…………).
With a little attention to detail, you can use the heat of the sun against one side of your house to enhance a ‘chimney effect’ to increase a drafting effect to move fresh air through the house. If the sun is baking one side of your house, open the top floor windows on that side, and open the downstairs windows on the shady side. The heated air in the upper floor rooms will expand and rise out of the open windows, pulling air inside the house behind it. The denser, cooler air near the ground on the shady side will be pulled in to replace the air moving up to the hotter floors. Of course, it might be a negligible draft, and the temperature gradient in the shade may not be much better, but it will help at least a bit.
Most people don’t realize that by flicking a switch on the fan body to reverse the spin of the fan, they will save lots of money on heating and be much warmer in the winter as well! Just as the fan pulls cooler air up from the floor in the summer and mixes it with the rest of the room, by reversing the fan in the winter, all the hot air that is trapped up by the ceiling (that you paid for with your radiators), will be pushed down into the room and mix for a more even, comfortable feeling.
I have a friend who has a house that was built with a deck off his kitchen/living room with a southern exposure. It is a beautiful, expansive deck and is bathed- as they wanted, in sun most of the day. When we visited it was a very hot day, they have no air conditioning and the deck-side portion of the house was sweltering. My friend was laying on a couch inside with a box fan, bungee corded into an open deck window blasting a high speed stream of air from the outside deck into the house. He apologised that it was so hot but that was as fast as the fan could could run, but it was still unbearable.
Of course all of our windows have fly screens, making sure that all the critters swarming around during the night, don’t find their way into the house. Sometimes I hear one of those big moths ramming its head against the flyscreen trying to get in.
We are lucky, because we have so many windows and more than that, we are surrounded by trees that protect us in the wintertime from the fierce winds from the north and provide us with lots of oxygen and shade the rest of the year.