Architekt: Alberto Campo, Baeza
Projekt: Casa Guerrero
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; what 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 employed this passive solution 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 ventilation is the use of environmentally-friendly systems that do not require any automated or mechanical solutions. In addition to being more ecological, natural ventilation is also more cost-efficient, and relies on natural external factors such as the wind and the temperature of the interior space and its surroundings.
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 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 in buildings located in climatic zones with higher temperatures, as it creates constant air renewal within the building, reducing the internal temperature.
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.
In vertical buildings, the chimney effect is constantly used. Cold air produces pressure under the warm air, forcing it to go upwards. In this case, however, opened areas 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 automated ventilation solutions in their projects, and have 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 much air is 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 with curved walls and partitions allow for more air circulation. Other influential factors include local climate, proximity to rivers, lakes, or the sea, and pollution rates around the project.
The Eastgate / Mick Pearce
The Eastgate Center employs passive and energy‑efficient climate control solutions to cool residents, inspired by termite mounds. 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-conditioning is crucial. However, doing so has immediate and long-term costs, so the architect created a self-regulating ventilation system that would maintain the building’s temperatures to suit workers and residents.
Obafemi Awolowo University / Arieh Sharon and A.A. Egbor
Lee House / Eduardo Glycerio + Studio MK27 – Marcio Kogan
Porto Feliz, Brazil
Farming Kindergarten / VTN Architects Bien Hoa, Vietnam
Vedana Restaurant / VTN Architects Vietnam
Stacked House / Studio Lotus New Delhi, India
Jalal-abad Villa / Hajm.e.Sabz Jalal Abad, Iran
Laayoune Technology School / Saad El Kabbaj + Driss Kettani + Mohamed Amine Siana Safi, Morocco
Ventilation Towers for the Northern Link / Rundquist Arkitekter Stockholm, Sweden
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