Evaluation of the material selection criterias on healthy building design

People, by nature, tend to create a shelter by using materials readily available to them. With the help of technology and the expansion of the available resources, societies developing and gaining more information day by day, have been constructing more practical structures but sometimes they are more threatening also to human health. Because of the improved industry, rise of the economic inadequacy and the awareness of the work variety, villagers who have fewer materials and opportunity moving to the bigger cities, have enabled the rapid growth of the urban areas. Population growth and industrial development have caused a decline in the quality of the urban environment. Due to industrial development, natural materials have simulated using artificial materials. Biological structures that are made of artificial materials have begun to adversely affect human health. The basic need of a human being is to lead a healthy life. Since people spend 90% of their life indoors, the main function of a building should be providing a healthy environment for its occupants. A building should meet its occupants‟ biological, psychological, social needs through its quality indicators related to the outdoor-indoor environmental characteristics. Buildings, which are designed, constructed and presented in a health-supporting condition, may lose their healthiness during the using period. Building Biology can be defined as the study of the relationships between people and their constructed environment. It is a science that leads to natural healthy ecological buildings that exist in harmony with the planetary environment. The main aspects of building biology are interior climate, heat and moisture comfort, air quality, radioactivity, electro-climatic pollution, acoustic violence and natural lighting conditions and its effects. Indoor air quality has a significant influence on the main purpose of a building which otherwise is providing a comfortable environment that meets the need of human beings. Human and environmentally friendly buildings should be able to take part in the ecological cycle of the local topography and should not stand as a foreign object, instead, it should reflect its locale. In this respect, the building has to be constructed with the natural materials that were provided from where the building will stand. In order to design a healthy building, the users have to take part in every stage of the construction. In today's world, people still tend to buy psychologically, sociologically and biologically unhealthy materials which adversely affect their health. Building materials play a very important role to create ecologically and sustainably healthy environment. In order to construct a sustainable building which is friendly with the human and the environment, the building materials have to be chosen accordingly. This creates an environment that would least threaten human health. It is advised that the building materials have to be selected as looking through their specifications such as durability, biologically demountability, lower energy consumption, least environment impact, recyclability, low levels of radiation, produced and used in local topography, natural, materials that have lower water consumption, least water pollution impact, minimum processed and doesn‟t contain harmful chemicals as pigments, thickeners, fire retardants so on. Every material has a life cycle. When planning a construction, every phase of the materials should be considered i.e. raw material acquisition, production, application to the building, usage, disassembly, recycling, reuse, and disposal. According to the studies, 65% of our buildings are polluted, sometimes as much as five to ten times higher than outdoor city pollution. The harmful gasses, volatile organic compounds, particulate matter, lead, asbestos, and dust have a magnificent role in indoor air quality. They can cause diseases such as cancer, asthma, allergic reactions, pulmonary fibrosis and much more. It is possible to avoid the pollution by reviewing material sources. Some of the hazardous effects of these substances on health are known; however, many have likely not yet been documented. The concept of Building Biology arises at this point. With the help of this concept, the principle of human guides himself to nature, not the vice-versa has become important. Researchers proved that indoor air quality is polluted by the harmful materials used in construction. This causes Sick Building Syndrome as a result of toxic gasses, VOCs, bioaerosols, pesticides which become an increasingly common problem. SBS symptoms can not be realized as the other illnesses and the symptoms come out even the user leaves the building. SBS is a very common problem and causes diseases such as cancer, asthma, allergies, spasm, skin problems, headaches and much more. Researchers have shown that, healthy circumstances cannot be maintained in buildings that are newly developed or improved; furthermore, it is reported that 30% of the buildings caused "Sick Building Syndrome". In order to understand the symptoms of SBS, both the building and the users have to be controlled. According to the researches, women and children are more sensitive than men when it comes to the topic of SBS symptoms. Building biologists are the people who help to design a healthy building and the environment. In the process of the construction, building biologists, users, engineers, architects, third parties should be in coordination. Additionally, the building biologists should work in coordination with the medical doctors. Bioclimatic Building Analyses which is created by the Institute of Building Biology and Sustainability arises at this point. In order to create a healthy environment, the measurements held periodically. Dealing with this subject, fields, waves and radiation, indoor toxins, fungi, bacteria and allergens, indoor pollutants and indoor climate can be measured with the specific measurements. It is essential to provide basic principles so that humans can continue their vital activities and maintain optimal health. These basic principles which occur with the help of Building Biology (biological, psychological and by meeting social needs) accelerate the process of creating a positive environment for people. To create livable environments on behalf of future generations, using material that not only looks beautiful but also is environmentally friendly, durable, recyclable, energy-efficient, and economical, thoughtful selection is necessary. Studies have proved that unnatural environmental conditions created by unhealthy building materials spread various pollutants threatening human health. In this study; At the second part, the definition of building biology, the basic needs of a human being, the basic principles in order to design a healthy building (indoor and outdoor) will be discussed in detail. At the third part, quality criterias of a healthy building will be defined, the indoor air pollutants such as harmful gasses, VOCs, bioaerosols, PM and odors will be described. In addition, in the light of Building Biology, moisture control, lighting, heat control, acoustic control, radiation and electro climatic quality of indoor environment will be discussed in detail. Also Bioclimatic Building Analysis will be discussed in detail. At the fourth part: the basic criterias of material selection, the importance of LCA methodology, the effects of material selection to indoor air quality will be discussed. In addition, building material‟s lifecycle, source efficiency and their effects on human health will be discussed in detail. At the fifth part, building materials are evaluated based on Arıoğlu method.