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[stevejones123]

Quote

natural air flow can't cool if the air is hot

You don't understand how things work. It's not the airflow that's doing the cooling it's your body. Your body is in fact acting as an air conditioner. It sweats. The liquid then evaporates. Evaporation uses heat and that heat comes from your body which thus cools down. However a given amount of air can only contain a given amount of water vapor, which is why you often find yourself covered in sweat that has not evaporated. Airflow increases the amount of air that flows over your body, thus increasing the amount of sweat you can evaporate, thus increasing the cooling of your body that is providing the heat for the evaporation.

You can certainly live comfortably without air-conditioning in most of the tropics; I have a house in Sri Lanka and the average maximum temperature is between 29 and 31 Celsius. The average maximum temperatures for Bangkok are from 31-34, averaging 32, edging towards the uncomfortable zone.

The point is that a house built for maximum cooling without air-conditioning is going to be built on diametrically opposite principles to one built with air conditioning in mind. If you are building without air conditioning you want high ceilings (eleven foot at least), because hot air goes upwards,  and lots of ventilation points. Wiht AC you want low ceilings so there is less air to cool and almost hermetically sealed so the cold air doesn't escape.

There are places in the world where you can't live comfortably without air conditioning (much of Saudi Arabia and Dubai spring to mind), and cars need it because the metal heats like a furnace and driving with the windows open is more energy inefficient, but to talk about it as a necessity, or even advisable, in most places is little more than self-justification.

[pkrv]

stevejones123, on 2009-11-12 17:03:26, said:

Quote

natural air flow can't cool if the air is hot

You don't understand how things work. It's not the airflow that's doing the cooling it's your body. Your body is in fact acting as an air conditioner. It sweats. The liquid then evaporates. Evaporation uses heat and that heat comes from your body which thus cools down. However a given amount of air can only contain a given amount of water vapor, which is why you often find yourself covered in sweat that has not evaporated. Airflow increases the amount of air that flows over your body, thus increasing the amount of sweat you can evaporate, thus increasing the cooling of your body that is providing the heat for the evaporation.

You can certainly live comfortably without air-conditioning in most of the tropics; I have a house in Sri Lanka and the average maximum temperature is between 29 and 31 Celsius. The average maximum temperatures for Bangkok are from 31-34, averaging 32, edging towards the uncomfortable zone.

The point is that a house built for maximum cooling without air-conditioning is going to be built on diametrically opposite principles to one built with air conditioning in mind. If you are building without air conditioning you want high ceilings (eleven foot at least), because hot air goes upwards, and lots of ventilation points. Wiht AC you want low ceilings so there is less air to cool and almost hermetically sealed so the cold air doesn't escape.

There are places in the world where you can't live comfortably without air conditioning (much of Saudi Arabia and Dubai spring to mind), and cars need it because the metal heats like a furnace and driving with the windows open is more energy inefficient, but to talk about it as a necessity, or even advisable, in most places is little more than self-justification.

An indebth reply but you forgot humidity - If the air is saturated yes you sweat but it doesn't go anywhere.

For me green means trees, plants, funny wildlife, I think I have a dinosaur in 'my' tree, god it is a big lizard, and there are a few funny squirrels and all sorts of other stuff. AND I with help have worked out how the tree can tell if it is going to rain.  You think I am kidding?

Edited by pkrv, 2009-11-13 00:25:42.

[stevejones123]

If there's 100% humidity then the sweat won't evaporate and there'll be no cooling.

If there's 10% humidity then the sweat will evaporate and you won't need airflow.

It's for the intermediate humidities that airflow provides cooling.

Bangkok seems to have a relative humidity some degrees higher than where I am in Lanka. That together with the couple of degrees higher temperature is probably enough to tip the scales into feeling uncomfortable with no air conditioning. I was using the AC when I was in Bangkok despite the exorbitant resale price.

[pkrv]

stevejones123, on 2009-11-12 18:10:04, said:

If there's 100% humidity then the sweat won't evaporate and there'll be no cooling.

If there's 10% humidity then the sweat will evaporate and you won't need airflow.

It's for the intermediate humidities that airflow provides cooling.

Bangkok seems to have a relative humidity some degrees higher than where I am in Lanka. That together with the couple of degrees higher temperature is probably enough to tip the scales into feeling uncomfortable with no air conditioning. I was using the AC when I was in Bangkok despite the exorbitant resale price.

Great reply - You actually did not miss the point at all - but instead you expanded on it.

Humidity after the rain in Bangkok can hit about 100%.

You are looking at two different aspects here houses and condos. For me all I can do is ask for more statement trees/green space  because a condo is all we can buy - One step at a time, and yes my two weatherstations in Bangkok take second place to the rain predictions of my tree.

http://www.thaivisa....ing the weather