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- 1 Sustainable Architecture
- 1.1 Energy Aspect
- 1.2 Resource aspect
- 1.3 Climate aspect
- 1.4 IT aspect
- 1.5 Open source aspect
- 1.6 Sustainable urbanism
- 1.7 Certification of sustainable architecture
- 1.8 Possible Problems
- 1.9 Categorisation of sustainable architecture
- 1.10 Related projects on the FH-Aachen
- 1.11 Related projects in the area (Aachen)
- 1.12 Related international projects
- 1.13 References
- 1.14 Internal links
- 1.15 External links
In the year 2013 38% of the total annual energy consumption in Germany was due to heating and lighting. Through sustainable architecture, it is possible to minimize the negative environmental impact of buildings through efficiency and moderation in the use of materials, energy, and development space. Sustainable architecture, also called ecological design ensures that the decisions made by us today will not effect the fates of future generations. The main motive of an ecological design is to reduce the negative impacts on the environment because of the buildings built. The major consideration of sustainable architecture is that the design of the buildings reflect an energy and ecological preservation. Another important goal is to maximise the energy efficinecy of the building throught its entire life cycle, through a life cycle assesment (LCA).
When a buildings' energy efficiency throughout its entire life cycle is appraised, grey energy is an important factor in this consideration. Grey energy is the hidden energy that a product has, which encompasses the entire energy needed throughout the product's life cycle from its production to its disposal. Many people believe that modern products use less production energy compared to decades ago thanks to newer production technologies, this however is a misunderstanding. In order to calculate the grey energy, many factors need to be considered, such as the amount of energy needed to extract the raw materials, transporting and transforming the raw materials in order to manufacture the final product. The energy usage for packaging and transporting the final product to the user, product handling, collecting, recycling or disposing of the product should also be calculated so that the grey energy amount is as accurate as possible. The grey energy of a residential building, assigned over the lifespan of its different components, is roughly 30 kWh/(m²·a) When a building is demolished instead of being repurposed, this grey energy is lost and a much higher amount of energy is needed to build a new building at the same spot.
Sustainable architecture tries to incorporate as much recycled or natural material into the buildings as possible. The reduction in use of new industrially refined materials results in a reduction of the embodied energy (energy used in the production of the materials) Traditional materials such as concrete and steel are, wherever possible, replaced by more sustainable alternatives, such as wood or recycled concrete. Some of the other major materials are adobe, clay, straw, sheep wool and locally obtained stone as well as recycled materials such as reused denim or insulation made from old newspapers.
There also is a strong focus on avoiding any materials that contain VOC (volatile organic compounds) that are in contained in most paints, wood products, adhesives and insulation. These components emit smog forming compounds and formaldehydes that can cause respiratory illnesses. Therefore, the usage of low or no-VOC materials reduces the emission of the smog forming compounds and at the same time improves the indoor air quality.
Despite the importance of materials to overall building sustainability, quantifying and evaluating the sustainability of building materials is difficult for any architect or other customer. The high number of competing and mostly imprecise eco-labels, has led to an inconsistency among sustainability criteria and certificates. Various proposals regarding standardization have been made but none has prevailed so far.
The accumulation and deposition of water form sources such as rain, snow and condensation for on-site use is a central part of every sustainable architectural concept. Water harvesting provides an independent water supply and reduces demand on wells which helps to sustain ground water levels. Harvested water can be used to supplement the main water supply to flush toilets, for irrigation, or with the proper treatment replace a main water supply altogether to serve as a source of drinkable water.
Some sustainable housing designs such as earthships have built in food production facilities. Using sewage water and integrated greenhouses it is possible to produce a variety of fruits and vegetables. Sometimes accommodation and nourishment of livestock such as chicken or fish is being provided by the building.
Waste management in general is the generation, prevention, treatment, reusage and residual disposition of solid and liquid wastes. Sustainable architecture focuses on the on-site use of waste management, incorporating things such as biological grey and sewage water treatment and recycling systems utilizing and nourishing plants and beneficial bacteria. These methods, when combined with on-site food waste composting and off-site recycling, can reduce a house's waste to a small amount of packaging waste.
The building sector contributes up to 30% of global annual greenhouse gas emissions and consumes up to 40% of all energy. Given the massive growth in new construction in economies in transition, and the inefficiencies of existing building stock worldwide, if nothing is done, greenhouse gas emissions from buildings will more than double in the next 20 years. Traditional buildings themselves are also one of the major players in annual Carbon dioxide emission.
Sustainable architecture aims to mitigate and sometimes even to completely neutralize emissions. This is achieved through highly energy efficient designs, built in energy production and on-site waste management. It also considers how future climate changes might influence buildings and their occupants to adapt to shifts in local and global climate, in order to retain their inhabitability.
Organisation and management of all the different aspects (smart home...)
Industrial processes and systems in a house that pays particular attention to increasing the quality of life, safety and an effective usage of energy based on a network of automated processes and devices that can be controlled remotely are called smart home. This includes both the networking of devices such as lamps, fridges and washing machines and the cross-linking of electronic elements for instance, central storage and a home wide usage of video and audio. The network of devices is mostly programmed based on the consumer's preferences, and information can also be stored, accessed and controlled via the internet or applications on smartphones, when the equipments are tagged. Smart metering, a similar process, is when the energy consumption is intelligently regulated by measurements.
Open source aspect
In architecture, open source as a development model promotes a universal access via a free license to a design's blueprint, and universal redistribution of that design or blueprint, including subsequent improvements to it by anyone. It also helps to make sustainable architecture available to communities in developing countries.
Architecture for Humanity
Architecture for Humanity is a global network of architects, designers, and other building professionals working to bring design, construction and development services to communities in need.
After hosting a series of open design competitions the organization began taking on a number of built projects, pairing local communities with design professionals to develop a ground up alternative to development and reconstruction. In 2005 they adopted an 'open source' model and were the first organization to utilize Creative Commons licensing system on a physical structure. To date it has worked in twenty eight countries around the world and has completed over 245 projects. Collectively more than 700,000 people are living, teaching and working in buildings designed by Architecture for Humanity design fellows, members and volunteer design professionals. The Open Architecture Network, the first open source system for supporting sustainable and humanitarian design and architecture was developed, which includes project management, file sharing, a resource database and online collaborative design tools. 
Sustainable urbanism aims to close the loop by eliminating environmental impact of urban development by providing all resources locally for example producing electricity and food within the city. It looks at the full life cycle of the products to make sure that everything is made sustainably. All buildings in a sustainable urbanism concept are built to highest energy efficiency standards.
Density, plays an important role in sustainable urban development because it supports reductions in per-capita resource use and benefits public transit developments. High density reduces the dependence on private automobiles, inefficient infrastructure, and reduces the loss of farmlands and natural habitats, pollution.
Sustainable corridors, another part of sustainable urbanism, are similar to a wildlife corridor in that they connect one area to another efficiently, cheaply, and safely. They are accessible to all people in the community to provide a convenient mode of transportation through public transport and short walking distances. Sustainable Corridors also include biodiversity corridors to allow animals to move around communities so that they may still live in and around cities. 
Two basic concepts: -Decentralisation(meaning every builing takes care of its own energy production, waste management...) [earthship] -Interconnection (Buildings share energy production,...)
Where does it make sense to interconnect? Where to decentralize?
Certification of sustainable architecture
There isn’t one globalized certification but many, depending on the country. In Germany, the system that is favored is DGNB. It delivers an objective depiction and appraisal of the sustainability of buildings and urban districts. The minimum requirements that need to be met in order to be certified as a sustainable building by DGNB is:
• An Indoor Air Quality of –VOC (SOC1.2)
• Design for all (SOC2.1)
• Legal requirements for fire safety (TEC1.1) and sound insulation (TEC1.2)
DGNB takes into account environmental, economic, sociocultural and functional, technical, process and site quality. The quality is thoroughly determined throughout the building’s entire life cycle. Since this system is very flexible, it can also be used internationally since it can be specifically tailored to various uses of a building and can also accommodate specific country requirements. A minimum level needs to be reached in order to achieve certification and there are 3 levels, bronze, silver and gold.
LEED Certification, a system that was developed by the U.S. Green Building Council, is the chosen standard for measuring the sustainability of a building in the United States and other countries around the world. A building that has achieved this certification is definitely a ‘green’ building. There are many incentives offered by state and local governments for being a certified green building. This system was designed to maximize profit while at the same time minimizing the effect on the environment and insuring that the occupant’s health and well-being is bettered.
There are four levels of certification:
Credits are accumulated in five categories:
• Sustainable Sites
• Water Efficiency
• Energy and Atmosphere
• Materials and Resources
• Indoor Environmental Quality
BREEAM, short for Building Research Establishment Environmental Assessment Methodology is the world’s longest established and most widely used method of assessing, rating, and certifying the sustainability of buildings in the UK and in more than 50 countries around the world. It was first issued by the Building Research Establishment (BRE), a Founding Member of the UK Green Building Council, in 1990. BREEAM is the preferred scheme for a number of the national Green Building Councils across Europe, including the Netherlands, Norway and others.
One of the main problems with sustainable architecture ist that initial investments have to be made. The most ecological solution might not necessarily be the most cost-effective one in the short run or the most cost-effectve one at all. Research studies have however shown that constructing a sustainable building often adds little to no capital cost to a development project. Even if additional costs are acquired, these expenditures are compensated over the life cycle of the building by the lower operating costs.
Another point is that most people have not yet developed the proper mindset towards halting or preventing climate change. This is, of course, not only limited to green architecture, but also applies to all aspects of life. Even though climate change and green solutions are topics that are familiar to many people due their occasional appearance in the media (compared to some decades ago), they are nevertheless nothing that people actively change their lifestyle for. Other criteria, such as comfort, price or availability are still prevailing when having to decide which product to buy, how to live, how to travel or transport something etc. Hardly anyone will deny himself of something he/she desires only because it is not sustainable enough. Solutions like smarthouses kind of recognize this problematic and are very helpful for people to get the most ressource savings without refraining from anything, but it is obvious that more can be achieved if only the attitude were different.
A third point, somewhat connected to the previous one, is the impact green solutions can have on the social stuctures currently existent. Often the most ressource-efficient path is to interconnect adjacent buildings in terms of heating/cooling, electricity or water supply, making them to a green complex, which in return lead to higher density and homogenization. For most people however houses are, just like cars, a status symbol - a possibility to express uniqueness, taste and social standing.
Categorisation of sustainable architecture
Passive solar design involves harnessing the energy emitted by the Sun without the usage of photovoltaic cells or hot water panels, in other words, active solar devices. Materials with high thermal mass are used in order to retain heat because they are strong insulators, which ensures that the heat in the house does not escape into the environment. The usage of sustainable or recycled materials, photovolatic cells, waste water treatment, rainwater collection and solar hot water is also included in a passive solar designed building.  
Low energy design also encompasses solar shading, the usage of blinds, shutters and awnings. These reduce the amount of energy needed to cool a building using artificial means. Planting trees near windows will also help keep the building cool. Another element in a low energy design is a low surface area to volume ratio. Centralized structures, for example, comply this ratio, and this helps to reduce the amount of heat loss.
A well insulated building is the most cost effective factor to a HVAC-system, a heating, ventilating and air conditioning system. In an efficient building, more ventilating capacity is normally needed in comparison to heat generation, in order to get rid of the polluted indoor air. Energy is mostly lost due to water, air and compost circuits flowing out of the building. These losses can be minimized by the usage of an onsite recycling system that can recapture the energy from waste hot water, or stale air and pump it into the fresh cold water or air.
HVAC motors that are made out of copper have a higher efficiency compared to other metals and this in turn insures the sustainability of a building's electrical components. Proper site and building orientation also increases the performance of a HVAC systerm.
Buildings are aligned in such a way, that they catch a maximum amount of sun for heating and solar electricity production. Windows are placed on walls that face the sun in order to admit light and heat (for example: in the northern hemisphere- there are more south facing windows than north facing ones in a building). There are many window types such as double or triple glazed windows and low emission coated windows. The glazed windows are insulated, which means they are gas filled spaces in between the glasses. These are better than single pane windows in order to minimize heat loss through the windows. The houses are normally shaped like a horseshoe so that the amount of natural light obtained, especially during the winter months, is the maximum amount possible. The roof and walls facing the north, east, and west are insulated massively so as to prevent any loss of heat.
In parts of the world where colder climates prevail, heating is a major concern for sustainable architecture because it is the largest energy drain whereas in warmer climate areas, keeping the temperature low is a challenge. That is why the materials used to build a building in these areas are different. Masonry building materials that have high thermal mass are used in order to retain the coolness of the night throught the day in warmer climate areas. A single story building is also a better design for these areas to maximise the surface area and heat loss. Another feature of this design is the ability to capture the cool wind and use it to reduce the indoor temperature. An integrated system, a mixture of well insulated walls, heat recapture and renewable energy sources increases the efficiency of a building situated in an area with four seasons. The sources for energy are active or passive solar water heating, solar panels, wind turbines and heat pumps.
An energy-plus house unlike a passivhaus, a house that has an ultra low energy usage, produces more energy using renewable energy sources than the amount of energy that it imports from external providers. An energy-plus house uses microgeneration technology and low energy building techniques to generate and minimize the energy needed to sustain it. This technique comprises of highly energy efficient fixtures and appliances and passive solar building design, insulation, site selection and building placement.
Zero energy House
A zero-energy building, also known as a zero net energy building is a structure with zero net energy consumption, meaning the total amount of energy used by the building on an annual basis is roughly equal to the amount of renewable energy created on the site. It is a basically a development of the passive house concept, including all its advantages like strong insulation and controlled airflow. In contrary to a classical passive house however, the zero-energy house actually produces the energy it requires on its own. This is usually achieved by integrating solar cells/wind turbines and rechargable batteries or other energy storage capabilites (for when the sun is not shining or the wind is not blowing). This features have as a consequence that many projects involving zero energy buildings do not focus on single building, but on a complex of many buildings. This is because energy harvesting is most often more effective (in cost and resource utilization) when done on a local but combined scale, like a group of houses, cohousing, local district, village etc. rather than an individual basis. Statistics show that an energy gain of up to ca. 7% can be achieved by eliminating losses caused by the electrical transmission and electricity distribution. Due to their features zero energy buildings can't be built anywhere. Instead they require proper topographical conditions and therefore pose an interesting challenge for architects.
A modern approach in architecture is the implementation of electronical control systems to automate processes or control devices in a building. While the term smarthouse is commonly used in conjunction with entertainment devices like TV, Hi-Fi and PC, it also has an high ecological impact. Smarthouses are buildings equipped with sensors connected to one or more controllers. This allows the resident to adjust devices remotely or even let the system regulate everything automatically based on a time-scheudle or sensor readings. Interconnecting light controls, window coverings, HVAC and house heating in this manner makes it possible to maintain high living comfort for the residents, while reducing the power consumption by the maximum possible amount. Many home controllers have built-in monitoring systems whereby they calculate and log usage by all connected devices, giving the home owner heightened awareness and the knowledge to make changes as necessary. These systems can even be accessed over the Internet from anywhere in the world so the homeowner can adjust consumption any time, anywhere.
Related projects on the FH-Aachen
Related projects in the area (Aachen)
The BoB AG is a company, specialized in planning and constructing unique, ecologically sustainable office buildings. It has wide know-how and various solutions to the requirements a building has to face in order to be energetically and ecologically efficient: heating, lighting, airflow etc. The building's thermal insulation meets the requirements of a passive house. It terms of heating, the building uses a combination of geothermal energy, paired with thermal activation of concrete and heat pumps. The so called Laser Cut Panels are a development, designed to maximize the usage of sunlight by reflecting it in a proper way over the ceiling. That way areas that do not have access to direct sunlight still dont stay dark. The company also implements smarthouse concepts by using brightness sensors and autmatic light regulation to maintain a constant light instensity throughout the day, no matter how late it is or how sunny or cloudy the day is. The standard variation of the BoB building is awarded with the silver seal by the German Society for Sutainable Construction (Deutsche Gesellschaft für nachhaltiges Bauen) and it can even achieve the golden seal, provided the location the building is supposed to be placed meets the geographical and topological characteristics to make it that efficent.
Related international projects
Plantagon International AB is a Swedish company founded by Hans Hassle and the native American indigenous people of Onondaga Nation on January 29, 2008. The company's focus lies in the sector of urban agriculture with it's signature project being the Vertical Symbiotic Greenhouse, which is planned to be built in Linköping, Sweden. A vertical farm is a skyscraper with vertically inclined floors and windows prevailing over walls (for maximum sunlight usage), in which plants are cultivated. This form of urban agriculture is environmentally friendly, first of all because it uses the heat and the carbon dioxide already existing in the cities and also because it eliminates the pollution that the transportation of the products to the consumers would have caused. One of Plantagon's innovation consists of having successfully eliminated the need for artificial lighting through a transport system which moves cultivation boxes from ceiling to floor in a slow pace. Hence, even distribution of available natural light reaches the plans. The construction began in the first quarter of 2014, with a further project being planned for Botkyrka, Sweden.
An Earthship is a unique type of passive solar house that is made of both natural and recycled materials (such as earth-filled tires), designed and marketed by Earthship Biotecture of Taos, New Mexico. Earthships are primarily designed to work as autonomous buildings using thermal mass construction and a natural cross ventilation that is assisted by thermal draught to regulate indoor temperature. Earthships are built to utilize the available local resources, especially energy from the sun. For example, specially angled windows on sun-facing walls admit lighting and heating to maximize natural light and solar-gain during winter months. Electricity is generated through photovoltaic or wind turbines, sewage is treated on site by s specially designed system which makes use of plants and bacteria. The thick and dense earth-rammed tire walls, through varying amounts of sunlight and shade, provide thermal mass that naturally regulates the interior temperature during both cold and hot outside temperatures. All walls, some of which are built from empty bottles or tin cans are usually thickly plastered with adobe. The roof is made using trusses or made from wood which rest on the walls. The roof as well as the north, east and west facing walls of an Earthship are also heavily insulated to prevent heat loss.