1.0 Introduction
Natural ventilation is the process of supplying and removing air by means of purpose-provided aperture (such as openable windows, ventilators and shafts) and the natural forces of wind and temperature-difference pressures. In the process, fresh air is introduced and ventilated air is removed from an occupied space. The primary aim is to preserve the qualities of air. (Amit Gupta, 2006). It may also be used to lower the temperature inside an occupied area for thermal comfort. Basic Concept of Natural Ventilation
Source: Google
According to Eugenijakin et al. (2009), in Indoor Air Quality (IAQ), natural ventilation helps to eliminate odour, dust, excess humidity, smoke, heat and airborne bacteria. For a typical house, these …show more content…
In order to achieve good ventilation, an architect should able to adopt passive cooling approach in respond to the site’s micro-climate. There are eight factors determine wind flow inside a building; stack effect, building orientation, external obstruction, cross ventilation, air pressure effect, location of the openings, opening control and opening size.
Stack effect is the movement of air into and out of buildings, courtyard and air-well resulting from air buoyancy. Buoyancy occurs due to a difference in indoor-to-outdoor air density resulting from temperature and moisture differences. Building with 45° orientation facing towards wind path increase air movement compares to 90° orientation. When wind meets an obstruction such as a building or trees it is deflected and due to its momentum this creates positive and negative pressures over the surface of the building. Cross ventilation occurs when air enters on one side of the building, and leaves on the opposite side, but can also drive single sided ventilation, and vertical ventilation flows. Air flow occurs caused by difference pressure between indoor and outdoor air. Location of opening such as window determines air flows within habitable area. Opening should not higher or lower than living zone. In air principle, it flows from high pressure area to low pressure area. The air velocity increased after entering …show more content…
The extension may cause thermal discomfort especially to the room adjacent to road. Heat generates from tarmac being transfer into the room by convection process. It will contribute to accumulation of hot air inside the house.
Construction of solid high wall-fences around the house to provide privacy and security but it forbids exchange of air. Concrete or cemented floor surround the house increase the surface water and during a hot day, water vapour will formed. Water vapour is one of greenhouse gases that carry heat.
Thus, home owners should aware the consequences of over-renovation of their homes may cause thermal discomfort. They should consult experts’ in house renovation in order to create sustainable homes. With passive cooling methods, overhead cost can be reduced in a long run.
5.0 Conclusion
Natural ventilation as an alternative to mechanical ventilation has several benefits: low running cost, zero energy consumption, low maintenance and probably lower initial cost. It is also regarded as healthier, having less hygiene problems with ducts, and filters. The “naturalness” in the way that it connects with outside, often in conjunction with windows, is seen as a psychological benefit. Therefore as designer, one should consider natural ventilation in the design process towards sustainable
Natural ventilation is the process of supplying and removing air by means of purpose-provided aperture (such as openable windows, ventilators and shafts) and the natural forces of wind and temperature-difference pressures. In the process, fresh air is introduced and ventilated air is removed from an occupied space. The primary aim is to preserve the qualities of air. (Amit Gupta, 2006). It may also be used to lower the temperature inside an occupied area for thermal comfort. Basic Concept of Natural Ventilation
Source: Google
According to Eugenijakin et al. (2009), in Indoor Air Quality (IAQ), natural ventilation helps to eliminate odour, dust, excess humidity, smoke, heat and airborne bacteria. For a typical house, these …show more content…
In order to achieve good ventilation, an architect should able to adopt passive cooling approach in respond to the site’s micro-climate. There are eight factors determine wind flow inside a building; stack effect, building orientation, external obstruction, cross ventilation, air pressure effect, location of the openings, opening control and opening size.
Stack effect is the movement of air into and out of buildings, courtyard and air-well resulting from air buoyancy. Buoyancy occurs due to a difference in indoor-to-outdoor air density resulting from temperature and moisture differences. Building with 45° orientation facing towards wind path increase air movement compares to 90° orientation. When wind meets an obstruction such as a building or trees it is deflected and due to its momentum this creates positive and negative pressures over the surface of the building. Cross ventilation occurs when air enters on one side of the building, and leaves on the opposite side, but can also drive single sided ventilation, and vertical ventilation flows. Air flow occurs caused by difference pressure between indoor and outdoor air. Location of opening such as window determines air flows within habitable area. Opening should not higher or lower than living zone. In air principle, it flows from high pressure area to low pressure area. The air velocity increased after entering …show more content…
The extension may cause thermal discomfort especially to the room adjacent to road. Heat generates from tarmac being transfer into the room by convection process. It will contribute to accumulation of hot air inside the house.
Construction of solid high wall-fences around the house to provide privacy and security but it forbids exchange of air. Concrete or cemented floor surround the house increase the surface water and during a hot day, water vapour will formed. Water vapour is one of greenhouse gases that carry heat.
Thus, home owners should aware the consequences of over-renovation of their homes may cause thermal discomfort. They should consult experts’ in house renovation in order to create sustainable homes. With passive cooling methods, overhead cost can be reduced in a long run.
5.0 Conclusion
Natural ventilation as an alternative to mechanical ventilation has several benefits: low running cost, zero energy consumption, low maintenance and probably lower initial cost. It is also regarded as healthier, having less hygiene problems with ducts, and filters. The “naturalness” in the way that it connects with outside, often in conjunction with windows, is seen as a psychological benefit. Therefore as designer, one should consider natural ventilation in the design process towards sustainable