Environmental Sustainable Design - Coursework Example

Environmental Sustainability Design Name Institution Name Date Executive summary The World Commission for Environment and Development (WCED) in 1987 developed a document called the Brundtland Report. This was the first instance in which the notion of sustainable development was brought to the fore. Eco design is part of sustainability since it implies environmentally conscious product development as well as design or design for environment. This term describes systematic approach that aims at embedding environmental aspects during product planning, development as well as design process in the early stages. This implies that the environment is added as an approach during product development as well as other classical methods of functionality, ergonomics, safety, reliability, profitability, ergonomics as well as aesthetics. Table of Contents Executive summary 2 Table of Contents 3 Introduction 4 Applications of Engineering Science in Sustainable Building Design 4 The Science of Glazing for Energy Efficiency 5 U-Value 6 Visual transmittance 7 The Geometry and Orientation of Buildings 7 Materials of Construction 8 The Principles of Shading 9 Conclusion 11 Introduction This research paper has been divided into five sections that attempt to explain various aspects that relate to engineering science and architecture. The first section is about applications of engineering science in sustainable building design. This section explains how engineering science helped in ensuring that buildings designs give solutions to sustainability issues. The second section is about some of the engineering principles that need to be considered when determining the appropriate glazing materials. The third section is about information solar geometry can be used in developing houses that use minimum energy levels. The fourth section is about how courtyard style has an impact on thermal performance and comfort. It also explains how construction materials affect thermal performance of buildings. The last section explains how principles of solar influence choice of building shadings in Darwin and Melbourne. Applications of Engineering Science in Sustainable Building Design Sustainable design refers to the philosophy of developing built environment, physical objects as well as services that comply with the principles of economic, social as well as ecological sustainability. According to Evrard&Bodart (2011), products that have the greatest impact on man’s sustainability are buildings. They state that built environment uses about 40% of all our energy in conditioning them and uses about 8% of energy in developing the buildings. Engineering science has ensured that building designs offers solutions for sustainability issues that range from flexible usage of energy reduction measures, renewable energy, while maintaining and increasing comfort level of users. Sustainability is a crucial aspect in engineering science and architecture has an important role towards that towards direct sustainable development. There exist mixed performance towards realizing sustainable objectives, there exists various barriers which hinder progress and the process is very complex. When intricacy of design process, traditional approaches cannot be adequate and there is need urgent need for novel approaches to bridge the gaping crack between ‘Science (Engineering)’ and ‘Art (Design)’ worlds. A number of approaches have been instituted to ensure sustainable development, for instance, Zero Emission Buildings; these are buildings that do not emit carbon dioxide. Nonetheless, this novel target in design of building necessitates a different approach that departs from conventional buildings according to operation, construction and most importantly design. At the moment the goal is ambitious and can be attained by using renewable energy sources as well as low energy use of building. Complex design tasks necessitate collaboration of all design disciplines that are involved towards conceptual building design. Both engineers and architects should be able to handle challenges brought about by the new design goals. The Science of Glazing for Energy Efficiency Some of the aspects to consider when determining glazing materials include: heat gains and losses, shading as well as sun control, visual requirements (glare, view and privacy), ultraviolet control, thermal comfort, condensation control, energy requirements, daylighting, color effects. In a nutshell, the choice of glazing system is highly dependent on a myriad of factors such as local climate, use of the building, as well as orientation of the building. One needs to specify windows and glazing materials. For one to determine a window system he needs to determine the following aspects: shading coefficient (SC) or window Solar Heat Gain Coefficient (SHGC) and window U-value (Ander, 2014). For particular aesthetic as well as performance objectives it is important to determine tints and coatings. U-Value U-Value is fundamental when determining glazing material since it indicates the extent of heat flow as a result of convention, radiation and conduction through a window that results from differences in temperature between the outside and the inside. When the U-factor is high it implies that there is more heat which will be lost during winter through the window. U-value units are Btu/hr ft2F. Usually the U-factors range from 1.3 (aluminum frame single glazed window) to about 0.2 (low-emissivity coatings as well as insulated frames), windows that have a U-factor of 0.6 will lose twice amount of heat when it is in the same condition as one with 0.3 U-factor. The total window U-factor is higher compared to center-of-glass U-factors. Solar heat gain coefficient – it is important to consider solar heat gain when determining windows for passive solar home, this refers to solar heat gain coefficient, and this term replaces measurement with, shading coefficient. Solar heat gain coefficient refers to the amount of solar heat a window gains to the total solar energy that strikes the window. In other words, it refers to the fraction of solar radiation that falls on the window which is transmitted via the glass. The solar heat gain coefficient varies between 0 which implies that there is no solar gain to 1 which implies that there is 100 percent solar gain. Glazing that face the south direction need to possess high solar heat gain coefficient with sufficient U-value so that it can conserve heat during cloudy periods and at night, as well as low infiltration to ensure maximum efficiency. When the climate is colder it implies that more solar gain is required and therefore a higher SHGC. Visual transmittance Visual transmittance is another aspect to put into consideration when purchasing windows. Visual transmittance refers to the amount of light transmitted by a window. Visual transmittance is the percentage of light which passes through an open hole in the wall which is the same size of the window. Usually, tinted windows allow 15% of visual transmittance on the other hand clear glass allows up to 90 percent visual transmittance. Usually, windows that have 60 percent visual transmittance is clear and one that has below 50 percent looks dark. The Geometry and Orientation of Buildings House orientation 30o due south, due south is equivalent to 100% potential solar heat gained through windows. When a house is rotated within 30o of due south offers 90% of potential solar gain as well as enables latitude for adjusting the building to lot limitations. When the rotation is more than 30 degree it makes the architectural shading more intricate and can result in overheating which can have devastating effects on the house. Designing the size of the south glazing to meet house heat loss the size of glass used in south-facing glass can be determined by house heat loss, amount of sunshine, location, local climate as well as the intended thermal mass. In a good design, the south facing windows can be distributed across south wall to offer heat gain in many areas of the house n.a(2004). Configuration of thermal mass to ensure absorption of sunlight – brick, concrete masonry units (CMUs), concrete as well as tiles are some of the materials used during thermal mass in building. The level of glazing as well as insulations is instrumental in determining the mass required to keep house from overheating during day and reduces backup heat which is required at night. Directly irradiated thermal mass is more effective compared to thermal mass which gets reflect light only. It is important to use solar geometry when designing where to put the mass (n.a 2004). During summer glasses that face south should be shaded to avoid overheating. West, east as well as north facing glass provide cross-ventilation. West and east windows lose most of the heat that they gain. In regions that have hot summers are problematic because they face low solar angles during morning hours and late in the afternoon. The rooms also get cross-ventilation. Glazing is a fundamental architectural aspecttherefore the type of glass used is fundamental when putting east-west windows. Overheating can be reduced by glasses that have a reduced solar heat gain (n.a, 2004). West and east glass need to have appropriate shading. The best way of reducing summer heat is through by strategically planting tree outside. Bushes and trees which leaf out during summer and drop leaves during fall for lighting and ventilation while shading windows when it is hot outside. Much caution is supposed to be emphasizedso that the trees do not grow tall which eventually reduce lower branches therefore lowering its potential of shading. Materials of Construction Usually, courtyard houses are constructed contiguously and have natural cooling aspects in the design. Some of those aspects comprise of a courtyard that has fountain as well as room ventilation, double-glazed windows, basin,air-scoops which allows natural cross ventilation which includes external air from roof terrace to pass via party walls to the subterranean rooms’ (n.a 2004). Thermal mass is very appropriate in climates which have a large diurnal temperature difference. When diurnal variation exceeds 10oc a high mass construction is necessary. Denser thermal mass materials are very effective passive solar materials. When the material is dense it stores heat better. For any wall material to store more heat effectively it should have a high density as well as conductivity so that heat can penetrate during heat charging as well as discharging n.a(2004). Textured or dark materials absorb more light and re-radiate more energy compared to smooth, light, reflective surfaces. Materials with a high thermal mass are not good thermal insulator. Thermal mass needs to be used with insulation. Thermal mass needs to be effectively located and distributed. Direct locations that have heat storage mass get energy through solar radiation and are more effective compared to indirect locations which absorb heat through infrared radiation. Usually, thermal mass that collects indirect sunlight will require three to four times compared to thermal mass than those which use direct storage sunlight. Thermal mass should be distributed properly depending with the orientation of the surface as well as the desired time lag n.a(2004). The Principles of Shading Melbourne and Darwin require different location since both have different orientation to the sun. When the same approach is used in the two locations it will result in adverse impacts on the houses since it can result in overheating. Glass doors and windows have a crucial role in allowing entry of light and heat in a building, and they can also have a huge effect on consumption of energy. Care is always put to make sure that windows are sized, protected and positioned in a manner that there is reduced penetration of sunlight into internal spaces. Shading materials that are used in a building need to allow some sunlight to penetrate during under-heated seasons. Shading materials that are well designed can be instrumental in reducing building peak heat gain as well as cooling requirements and enhance natural lighting quality in buildings. Shading considers visual comfort of users through regulating glare and lowering contrast. Often this results in increased productivity as well as satisfaction. Shading devices give an opportunity for differentiating buildings. Materials used in shading is determined by the season since during cooling periods an external window shading provides a good way of preventing excess heat from getting into conditioned space. Different regions have different shading demands and this can be met by natural landscape or building aspects such as overhangs awnings as well as trellises. There are some shading devices which function as reflectors that bounce daylight into buildings. Overhangs provide an effective way of shading windows that face the south direction during summer since the angles of sun are at very high levels. Nonetheless, the horizontal device is not effective enough to block the afternoon sun to enter windows that face west direction during summer. Melbourne and Darwin have different orientation to the sun. When the same approach is used in the two locations it will result in adverse impacts on the houses since it can result in overheating. Different shading devices can be used in both locations depending with orientation to the sun. Shading devices can be grouped into five categories a) External shading devices – this device includes shutters, awnings, shades, rolling shutters as well as solar screens. Mostly, the structure of a house can be designed in a manner that protects windows which are directly exposed to sunlight. b) Internal shade for instance curtain and roller blind. This type of shades reduces entry of solar but it eliminates and lowers movement of air. c) Louvres – they are very attractive and allow they control amount of sunlight that enters a building d) Fixed overhangs – they protect walls as well as openings against sun and rain and give little effect on movement of air. e) Brise soleil – this refers to both vertical and horizontal projections over openings. It protects against glare and solar heating. Conclusion The paper has explained how engineering science can be integrated in architecture to ensure that buildings that are constructed are environmental friendly and there is little wastage of energy through use of appropriate strategies in tapping energy during and at the same time avoiding over heating of building through use of appropriate strategies. References Ander, G2014,Windows and glazing retrieved from http://www.wbdg.org/resources/windows.php Evrard, A &Bodart, M 2011,Archetiecture& Sustainable Development (vol. 1): 27th International conference on passive and low energy architectu,Presses Univ. de Louvain, Brussels. N.a 2004,Sustainable building – design manual: Sustainable building design practices. TERI Press, New Delhi, ND. Read More

Nonetheless, this novel target in design of building necessitates a different approach that departs from conventional buildings according to operation, construction and most importantly design. At the moment the goal is ambitious and can be attained by using renewable energy sources as well as low energy use of building. Complex design tasks necessitate collaboration of all design disciplines that are involved towards conceptual building design. Both engineers and architects should be able to handle challenges brought about by the new design goals.

The Science of Glazing for Energy Efficiency Some of the aspects to consider when determining glazing materials include: heat gains and losses, shading as well as sun control, visual requirements (glare, view and privacy), ultraviolet control, thermal comfort, condensation control, energy requirements, daylighting, color effects. In a nutshell, the choice of glazing system is highly dependent on a myriad of factors such as local climate, use of the building, as well as orientation of the building.

One needs to specify windows and glazing materials. For one to determine a window system he needs to determine the following aspects: shading coefficient (SC) or window Solar Heat Gain Coefficient (SHGC) and window U-value (Ander, 2014). For particular aesthetic as well as performance objectives it is important to determine tints and coatings. U-Value U-Value is fundamental when determining glazing material since it indicates the extent of heat flow as a result of convention, radiation and conduction through a window that results from differences in temperature between the outside and the inside.

When the U-factor is high it implies that there is more heat which will be lost during winter through the window. U-value units are Btu/hr ft2F. Usually the U-factors range from 1.3 (aluminum frame single glazed window) to about 0.2 (low-emissivity coatings as well as insulated frames), windows that have a U-factor of 0.6 will lose twice amount of heat when it is in the same condition as one with 0.3 U-factor. The total window U-factor is higher compared to center-of-glass U-factors. Solar heat gain coefficient – it is important to consider solar heat gain when determining windows for passive solar home, this refers to solar heat gain coefficient, and this term replaces measurement with, shading coefficient.

Solar heat gain coefficient refers to the amount of solar heat a window gains to the total solar energy that strikes the window. In other words, it refers to the fraction of solar radiation that falls on the window which is transmitted via the glass. The solar heat gain coefficient varies between 0 which implies that there is no solar gain to 1 which implies that there is 100 percent solar gain. Glazing that face the south direction need to possess high solar heat gain coefficient with sufficient U-value so that it can conserve heat during cloudy periods and at night, as well as low infiltration to ensure maximum efficiency.

When the climate is colder it implies that more solar gain is required and therefore a higher SHGC. Visual transmittance Visual transmittance is another aspect to put into consideration when purchasing windows. Visual transmittance refers to the amount of light transmitted by a window. Visual transmittance is the percentage of light which passes through an open hole in the wall which is the same size of the window. Usually, tinted windows allow 15% of visual transmittance on the other hand clear glass allows up to 90 percent visual transmittance.

Usually, windows that have 60 percent visual transmittance is clear and one that has below 50 percent looks dark. The Geometry and Orientation of Buildings House orientation 30o due south, due south is equivalent to 100% potential solar heat gained through windows. When a house is rotated within 30o of due south offers 90% of potential solar gain as well as enables latitude for adjusting the building to lot limitations.

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