Comfort

ECOPRODUCTS THAT CONTRIBUTE TO THE LEVEL OF COMFORT IN BUILDINGS

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What are buildings if not shelters, barriers to wind and rain and, sometimes, filters to light and heat?

Countless are the variables that influence them, from temperature to the elements, from day to night. They become refuges of artificial conditions, islands of tranquillity in a cumbersome world.

However, if architecture is climate, it is also true that many are the climate conditions that interfere with it: summer and winter, heat and lighting, interior and exterior, natural and artificial. In both traditional and contemporary architectures there are even environments that contribute to creating climates: sonorous, psychologic and even magical environments.

To study comfort in buildings is a hard task due to the complexity of climate conditions.

We should strive to understand climate in architecture in a broader sense, including in this expansion all environmental phenomena that affect a buildings inhabitants and their well-being as well as their perception of comfort, either thermic, visual, acoustic or otherwise.

In a stricter sense, thermic comfort is very susceptible to climatic conditions. Climates around the planet’s surface are also very diverse with varying temperature and humidity. They change according to the time of the year, the height of the sun and incidence of wind.

 

Hot and dry regions: very high daytime temperatures with significant drops at night. There is an intense direct solar radiation which is accentuated by low cloudiness and precipitation. This climate is characteristic of equatorial regions where vernacular architecture is typically compact, having thick walls and few openings in order to maximize thermal inertia and compensate exterior thermal variations. These buildings can be erected beneath ground level or resort to inner courtyards to create spaces protected from direct sunlight and cooled off by running water. These courtyards allow the architecture to conciliate with external conditions.

Figura 1. Arquitectura característica de zonas quentes e secas1.Typical architecture of hot and dry climates.

 

Hot and damp regions: even though temperatures are high they are not so extreme and have smaller fluctuations than in hot, dry climates. Cloudiness and precipitation are frequent with a rainy season during the year. In these climates solar radiation becomes more diffuse and humidity is permanently high. Traditional architectures in these conditions are characteristically lightweight, highly ventilated with all-around shading and no thermal inertia whatsoever. In these conditions buildings are usually long and wide and sometimes elevated from the ground in order to optimize air circulation.

Figura 2. Arquitectura característica de zonas quentes e húmidas2. Typical architecture in hot and humid climates

 

Cold regions: temperatures are low throughout the year and particularly low during the winter. There is low solar radiation and precipitation is often solid. In these conditions there is no verifiable humidity. It is a weather pattern characteristic of high latitude regions close to Polar Regions.

Architecture in these regions has the main purpose of preserving interior heat. For that reason buildings are compact, have small openings and are often round in shape in order to minimize the effect of cold winds. In a way these architectures resemble those of hot and dry climates in that their prime characteristic is to be able to counteract the thermal conditions of the surrounding environment.

Figura 3. Arquitectura característica de zonas frias3. Typical architecture in cold climates

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Temperate regions: in these areas climatic conditions vary the most throughout the year. Because of those variations architectural responses become more complex as they have to adapt, if only for short periods, to all of the weather patterns previously described.

The most prominent problems in these climates are therefore the mutations that occur in the weather at any given time of the year or day: extreme cold in the winter and extreme heat in the summer, both dry or damp, rivalling the more extreme regions with high instability in the intermediate seasons which can vary from intense heat to extreme cold in short periods.

These circumstances translate into architectural solutions with high complexity designs. These can incorporate flexible solutions such as: removable shading systems; transitional entrance spaces to create favourable microclimates; energy recovery systems for air conditioning; etc.

Figura 4. Arquitectura em zona temperada4. Typical architecture in temperate climates.

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It can be concluded that from knowing the configuration of a region’s climate it is possible to establish major intervention guidelines for architectural design in that area and still leave enough room for customized solutions. In this way we will be helping the environment by designing buildings suited for their climatic conditions which allows resources to be saved, namely in energy expenditures with air conditioning.

Conditions external to the environment affect each of us in a different fashion and provoking different reactions

 

What is comfort? 

The feeling of comfort experience by a human being on a given place is the result of a number of circumstances. These phenomena is actually more complex than it is seems. If the parameters for environmental comfort are quantifiable objective characteristics, then, the feeling of comfort is only relevant to each individual. Constraints unrelated to the environment influence us in different ways and cause us to experience them differently. They usually pertain to physical or biologic aspects (age, gender, genetics, etc.) and psychologic or sociologic circumstances (work, education, family, diet, etc.) inherent to each individual. Environmental comfort parameters that can be quantified in energetic terms are best suited to be independently accessed by users.

Comfort in a given environment is, therefore, contingent on the combination of these objective parameters with the circumstantial constraints that condition each human being’s reaction.

The following chart illustrates the three most common comfort criteria and relates them to the respective defining concept, measure unit, symbols and associated sensation.

TYPE CONCEPT SYMBOL UNIT SENSATION
Visual illuminance

(level)

E lux high/low
illuminance

(contrast)

L high/low
direction

(shading)

diffuse/directional
Acoustic sound level N db high/low
frequency (pitch) f Hz bass/treble
spectrum (tone)
direction difuse/directional
reverberation interval Tr s high/low
Hygrothermic temperature
air

Ta

radiation Tr
ºC
ºC
high/low
high/low
relative humidity Hr % damp/dry
air movement v m/s strong/weak
air composition clear/dense