Architekt: Alberto Campo, Baeza
Projekt: Casa Guerrero
Ort: Zahora
Automation is everywhere around us – our homes, furniture, offices, cars, and even our clothing; we have become so accustomed to being surrounded by automated systems that we have forgotten what life was like without them.
And while automation has noticeably improved the quality of interior spaces with solutions like purified air and temperature control, nothing compares to the natural cool breeze of mother nature.
But just like everything else in architecture, there is no one size fits all; whatย works in Tanzania cannot work in Switzerland or Colombia. This is due to several reasons, such as the difference in wind direction, average temperature, spatial needs, and environmental restrictions (or lack thereof). In this article, we take a look at natural ventilation in all its forms, and how architects have employedย this passive solutionย in different contexts.
What is ventilation, and why is it important?
Air movement is created by the rising of warm and the lowering of cool air. As the air above the land gets warmer, it rises and creates an area of low pressure. When air continues to rise, it cools and moves towards water surfaces, where it falls and creates an area of high pressure, and pushes cold air towards the land. This movement of areas is what creates the wind.
Types of Natural Ventilation
Natural ventilationย is the use of environmentally-friendlyย systems that do not require any automated orย mechanical solutions. In addition to being more ecological,ย natural ventilation isย also more cost-efficient, and relies onย natural external factors such as the wind and the temperature of the interior space and its surroundings.
Single-Sided Ventilation
Single sided ventilation is the use of openings on one side of a building. This is used to naturally ventilate the space of projects with limited area. Single sided ventilation systems are also used in projects where cross ventilation cannot be provided, due to structural or environmental constraints. Keep in mind though that this type of ventilation generates the least air circulation when it comes to natural ventilation systems.
Cross Ventilation
Cross ventilation is when the openings in a structure are arranged on opposite or adjacent walls, allowing air to enter from both sides, cross the space, and exit from the opposite direction. This system is usually used inย buildings located inย climatic zones with higher temperatures, as itย creates constantย air renewal within the building, reducing the internal temperature.
Stack Ventilation
Stack ventilation introduces cooler air from the outside into the building at a low level, which gradually becomes warmer as it gets exposed to heat sources within the space. This causes the now-warm air to rise and leave the space through openings situated at a higher level. Usually, stack ventilation is more effective in tall buildings with central atriums, but can also be useful in buildings where cross ventilation is not able to penetrate sufficiently throughout the space. In order for this ventilation system to work properly, the indoor temperature has to be higher than the outside, which is why it may not always be efficient enough to use on its own.
Chimney Effectย
In vertical buildings, theย chimney effectย is constantly used.ย Cold airย producesย pressure under the warm air, forcing it to go upwards. In this case, however, opened areasย in the project’s center or towers allow that same air to circulate throughout the indoor environment, leaving through the roof, clerestory, zenithal openings, or wind exhausts.
Natural Ventilation in Different Contexts
Whether it’s for environmental or economic reasons, some architects are unable to utilize automatedย ventilationย solutions in their projects, and haveย to rely on passive systems instead. For it to be efficient, natural ventilation relies on several factors. The overall shape, scale, orientation, location, and material used in a project can determine how muchย air isย entering and circulating within a space, and how efficient it is. In theory, air must enter and exit through openings in the architecture such as windows, facade perforations, doors, solar chimneys, or wind towers. In terms of structure, projects withย curved walls and partitions allow for more air circulation.ย Other influential factors includeย local climate, proximity to rivers, lakes, or the sea, and pollution ratesย around the project.
The Eastgateย / Mick Pearce
Harare, Zimbabwe
Theย Eastgate Center employs passive and energyโefficient climate control solutions to cool residents, inspired by termiteย mounds.ย The climate of Harare requires buildings to be cool all around the year, which means that the purchase, installation, and maintenance of a traditional air-conditioningย is crucial. However, doing soย has immediate and long-term costs, so the architect created a self-regulating ventilation system that would maintain the building’s temperaturesย to suit workers and residents.
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