With daily maximum average temperatures exceeding 30 degrees Celsius for 12 months of the year and monthly average minimums not dropping below 20 degrees, the importance of keeping workplaces and homes cool in Vietnam’s Ho Chi Minh City cannot be underestimated.
Whilst some may look to handle this by turning up the air-conditioner, a number of designers are leaving much of the air-conditioning to mother nature.
Take, for instance, the Green Industrial House designed by T3 Architecture – a new typology of sustainable housing which the firm has designed through its latest research into green architecture. The house uses an industrial style of design to create a space which is affordable as well as environmentally friendly.
In this instance, the architects have employed a number of strategies. A double ventilated roof in which the first layer is fibre cement and the second is palm trees with a light metal structure sitting in between enables air to ventilate through the roof space. A façade consisting of one brick/light concrete layer and another wood/bamboo sticks layer enables both ventilation and efficient sun protection for the façade. Large overhangs and pergolas are located to avoid allowing direct sunlight into the house and keeps the walls from becoming overheated. Landscaped features such as a pool, plants, natural soil and trees add freshness to the house.
T3 are not alone in their approach of utilising natural surrounds in order to achieve greater climate comfort – an approach known as bioclimatic architecture. In Indonesia, for example, the Biophilic Boarding House designed by Andyrahman Architect, which featured perforated walls to help the building stay cool in the East Java port city of Surabaya, made the short list for the World Architecture Festival’s Building of the Year in 2016.
In truth, bioclimate design is not actually anything new. In a recent edition of the bi-monthly magazine of the United States Green Building Council, for instance, Seattle based building consultant Patrick Leonard said that whilst designers of older buildings prior to the 20th century were good at adapting to climate in order to generate maximum performance, a degree of apathy had swept across those in the western world following the advent of air-conditioning as well as electric lights.
According to Charles Gallavardin, director of T3 Architecture Asia, the idea centres around returning to the core basis of traditional architecture from an approach perspective – albeit with ample potential to incorporate modern design styles.
Under this approach, Gallavardin says, you would typically utilise materials which originate near the site and orient your design around the sun’s orientation and the natural environment. Use of local materials not only reduces transport requirements but also facilitates integration of the building with its natural landscape from a colour and aesthetic viewpoint. Following the sun orientation and wind all year round enables you to look for fresh air in summer and insulation from the elements throughout winter, he says.
Gallavardin says there are several strategies to keep in mind with this type of design. First, it is important to have a roof which protects the building either from cold or overheating through a double ventilated roof with space which is sufficient so as to enable air to pass through and avoid heat accumulation. Whilst the first layer provides protection from sunlight, the second has sufficient insulation to prevent cool air from escaping from the room too easily.
It is also imperative, Gallavardin says, to avoid any direct façade exposure to sunlight in hot climates. In temperate climates such as Europe, using large south-facing windows and avoiding large windows plus insulating exposed walls on the west site delivers an outcome whereby the sun enters (and heats) the building during winter and the west façade is protected from overheating during summer. In multi-storey buildings, Gallavardin says double orientated apartments are critical as a means of promoting natural ventilation.
Speaking of large Asian cities, Gallavardin says obviating the need for air-conditioning completely is unlikely because of the requirement for closed environments indoors in order to control noise and pollution. Nevertheless, he says clever design could mean that building occupants might have to run air-conditioning at only 26 degrees rather than as low as eighteen degrees whilst remaining comfortable – with bioclimatic design achieving the desired temperature range and air conditioning subsequently being used simply from a comfort perspective.
“The manner of doing that is to design a bioclimatic building (who will become fresh or hot enough at all season), then, AC is just a manner of increasing the comfort as a secondary option,” Gallavardin said.
“First option being Bioclimatic architecture! Then, by adding ceiling fans, you can still reduce your needs of AC because it helps to improve the comfort of customers which the main issue.”