A friend was just telling me about how some ancient civilizations, like the Greeks and Romans, designed their buildings to have such an air flow that it would have felt like air conditioning. Now obviously it would be the same as what you and I think of air conditioning, but it would have provided cooler seating for those in the buildings. What I’m wondering is how did they create these air flows? What buildings had them, and to what degree did these designs really cool the buildings off; at all that is.
Building just a few feet below ground level can help a great deal. I have what is referred to as an English Basement style place (because there is no way you could sell a plain old basement for $350K) and in the summer when it’s 90° outside, I sense what feel like a 10° drop when I walk into my place, even though the a/c hasn’t been on all day. I can even leave the front and back doors open and get by most of the summer with very little a/c. In fact, when I turn on the a/c, it’s almost always because of the humidity rather than the heat.
I don’t know about the Greeks and Romans, but I live in a house which was built in 1910. It has very high ceilings and vents in the roof, which are the keys to keeping the rooms cool. The high ceilings help because the hottest air in the room rises to the top leaving cooler air below. The vents on the roof allow rising hot air to escape. That has the effect of creating a subtle air flow. The attic heats up, the hot air rises up and out through the roof vents, and cooler air is drawn in from below. The air vents have rotors on them, which turn as the air passes through them. You can see the circulation happening: the warmer the weather, the faster those rotors go (and the faster air is circulating through the house.)
The roof of my front porch limits direct sunlight shining into the house, but still allows enough indirect light to come in to keep the place bright during the day.
The final pieces of the puzzle are the big oak and hickory trees shading the house.
With all of those architectural and landscaping tricks in play I hardly need air conditioning in the summer. And that’s in muggy Atlanta.
I imagine the Greeks and Romans had similar methods.
One other factor which ties in with what Patty is saying. I have a cool cellar dug out below my house, so when the hot air is venting from the roof, the cool air from the cellar is being drawn up and into the house.
spoke- touched on a very important cooling feature which I believe originated in Africa, the porch. It keeps the sun off the exterior walls, keeping them cool, and keeps sunlight from passing directly through any windows to eliminate that solar heating.
In Anatolia and probably other places in the mideast, they built dwellings with “wind scoops”, which were basically a big pipe extending up through the roof, with the open part of the pipe pointing in the direction of the prevailing winds. So the winds would zoom down the pipe and blow through the house.
I can’t find any good sites at the moment, but this describes something similar, although in a different kind of dwelling.
Like others have listed there are many ‘tricks’ to keeping a house cool.
Houses in the desert that have very thick walls transfer heat very slowly. During the day while the sun shines on their surfaces they collect heat. By the time night falls the heat makes it’s way to the inside of the building to keep it warm at night.
Through the night the wall radiates it’s heat and loses it. Then the next day during the hot part of the day the inside wall will feel cool to the touch again.
Homes in seasonal areas use deciduous trees which give shade from the heat in the summer months, and when they lose their leaves in the fall, allow the sun to warm the house in the winter months.
Cross ventilation in homes is also key. As long as there is a slight breeze outside, opening windows on opposite sides of the house will immediately allow a cross draft. Apartments with windows on only one side will usually remain warm even with the windows open. If your lucky enough to have an apartment with north-south or east-west windows you can easily set up a cross draft to cool your place down.
Being very interested in Roman history, I have visited a good many Roman ruins and a small number of reconstructions and extant buildings.
Roman buildings do not have cellars as far as I can recall.
In general, Roman buildings have thick walls and small windows. I would think that this combination alone would be helpful in keeping the interior cool. Stone floors and tiled surfaces would help too. In England today, a thick walled house will stay cool on a hot day provided that you keep the doors and windows closed.
Those Romans who could afford it might have a form of underfloor heating; for really hot rooms the walls would be heated too. The heat was provided by a fire lit just below ground level and, I have heard, that this tends to be by the wall facing the prevailing wind. Without a fire, it might have been possible to get a slight cooling effect from natural wind, but I cannot imagine that this would have been significant.
It is just possible to get a cooling effect by letting air pass through or over a damp surface, some sort of matted material at a window. However, I don’t think there is any evidence for this in ancient times. This only really works if the humidity is low and in Rome itself, the summers are infamously hot and humid!
I am pretty sure that the same would go for Greek buildings.
I have visited old buildings in consistently hot countries, here the emphasis has been an extended roof giving plenty of shade and on letting air pass freely by having a minimun of walls and most of them louvered in some way.
When I was stationed in Germany, I would apply the principles of the Bournoulli effect to cool my non-air-conditioned barracks room. Just had to figure out which doors and windows to strategically open and close to get the air sucked out right.
Why do you think this? I mean it could be correct, but it seems to me that a porch it a Roman portico, and this architectural detail, barring any parallel discovery, is Greco-Roman in origin.
I’m not sure of the extent of their technology but it would be easy to duplicate today’s level of cool air by what Patty O’Furniture said along with an external watering system. I’ve seen older houses out West with a system that pours water down the outside wall. This evaporates and cools the wall (a good supply of water would be necessary).
From what little I’ve seen of Roman houses they did sink them down a couple of feet. If the floors had pipes under them and outside air was drawn through them then there would be a significant cooling effect.
I would add that they could also have used venturies to help pull in cooler air. I’ve seen outhouses that have venturies built into the exhaust vent. They are faced into the prevailing wind direction.
Man I knew I was going to get called on this. I can’t find a cite but recently I read that when the English were settling the New world, particularily GA and FLA (which they thought of as sweltering jungle) that it was a Jamacian slave(s) of African ancestory that showed them the benefits of a porch to a house in hot climes.
I can’t figure out where I read that now, but that is the gist of the article as I remember it. I’m not defending the scholarly merits of this theory, that is just what I remember of it. Sorry.
While all new buildings here now rely on air conditioning, they often build them with windtowers still. However these are non-functional, and merely for decorative purposes.
