The human body is equipped with a high efficiency envelope, skin, which is what protects the rest of organs. The skin is hardly comparable performance to anything we have been able to build, but we should serve as an example to our buildings, both the assessment and comfort is achieved within the same, as a source of inspiration to improve the envelopes of these.
Skin behavior respect to temperature variations is highly effective, because the skin pores are quickly adapted to the thermal situation. Given these variations, the pores open and transpire in quantity when temperatures rise, o well, close to the low temperatures, thus preventing heat loss from the body that protects.
With other states of measurable room for us, as are the RH air or wind speed, skin behaves not as effectively. While the first conductivity improves and therefore temperature losses, with the other reactions may occur within our body, as muscle contractions.
However, there is an element in the skin that give us optimum protection from radiation Thermal, making us vulnerable to its effects and greatly influencing us in our state of comfort.
It is called thermal radiation or heat radiation emitted by a body due to its temperature. All bodies emit electromagnetic radiation, its intensity being dependent on temperature and the wavelength considered. With respect to heat transfer is the relevant radiation within the range of wavelengths of 0,1μm to 100μm, thus covering part of the ultraviolet region, visible and infrared electromagnetic spectrum.
Therefore all bodies and objects around us emit radiation that contributes to better or worse in our comfort.
To try to convey to the reader as is reflected in our state of comfort radiation, will evaluate some highly significant examples showing us how the radiation is most relevant for human comfort than any of the other components exposed.
We know from our own experience how we can be comfortably under conditions of extreme temperatures. For example, this occurs in cases below zero degrees Celsius, as is the typical case of a day in the snow where the ambient temperature can be -5, yet it is a sunny day with abundant snow in our immediate environment.
How can you have that feeling of comfort at that temperature? This is thanks to the radiation from both the sun and snow, making our thermal sensation and comfort level incite us to stay in short sleeves while our body is perfectly located, without risk of any subsequent ailment by cold ambient. We know that this situation, and the temperature does not affect, if we could affect a strong prevailing wind, or high relative humidity, but ultimately the temperature is outside our state of comfort.
The second situation that could occur is, how to find ourselves in a room at 22 ° C but in a place where the walls are cold or wet, and in which despite the ambient temperature, our body senses cold areas or nonexistent sense of air currents that prevent us find comfortably in place, often leading to tired known pathological medical conditions.
These two examples are not enough, to assert that so far, room temperature, we consider as relevant, it is only a mere measurement, Consequently most of the state of the global environment.
Therefore, desgranamos that climate comfort of man is not so important if the temperature and radiation status of all elements around us. Therefore, the control and moisture infiltrations (current) must have a key role in the construction processes, further, is necessary to study the radiant state of the elements of the environment and thermally insulate, so that none of them becomes a sender or receiver of unwanted heat.
It can be said that the way to achieve the desired comfort happens to have controlled, more nearly average temperature of the environment, of bodies and objects around us with the air currents that could produce, both by wind and by thermal differences between these objects around us.
To achieve a stay that has the desired comfort level, is critical: homogeneity of the walls that surround, as well as the objects contained (avoiding thermal discontinuity in all), and the tightness of the enclosure to the outside. In this way we ensure the absence of thermal differences, current or high humidity. This is ensured by:
- The absence of thermal bridges
- The total physical continuity of the thermal envelope of the building (isolation) all their faces (walls, ceilings and floor)
- The tightness of the building with the outside
- The existence of strong elements of large mass that we act as homogeneous thermal batteries
These exacting standards, which are usually not follow conventional construction, are those that make the standards that we adopted for the development of our high efficiency Industrialized housing.
Mario Pírez, architect AIRO Building.