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Materials and Waste

When determining what materials should be chosen for the construction of a building, consideration must be given to a number of factors. It is vital that the building itself be constructed with the proper materials and create a limited amount of waste. This section of the report considers manufacturing process, energy consumed, waste created, potential health hazards, recyclables, resource use, and material/waste flows.

The construction and building process can have an enormous negative effect on our earth. Forty percent of the total material flow in the world economy (3 billion tons of raw materials per year) is consumed by the building industry.[i] Huge amounts of natural resources and materials are used during the design, construction, and lifespan of a building. Harvesting, extracting, and mining the raw materials alone creates large amounts of water and air pollution. Converting raw materials into the finished products that are used in the actual construction phase is very water and energy intensive. It pollutes the natural environment , not only threatening our own health, but also the health of the earth’s ecosystems.

One of the most potentially dangerous materials, at least in terms of extraction, is lumber . If not harvested in a sustainable way, the world’s great forests could very easily be destroyed through over-cutting. Approximately 3.5 billion cubic meters of wood are produced annually worldwide. Over one-quarter of that wood production is consumed by North America, Europe, and Japan alone.[ii] This demand spurs devastating harvesting practices in the world’s rainforests. If consumption continues at this rate, humans will have completely exhausted this resource in less than fifty years, destroying an incredibly important and irreplaceable ecosystem which supports billions of plant and animal species. Consumption of other natural resources and raw materials, including wood, is expected to increase into the future. Here, at the College of Saint Benedict and Saint John’s University , we have an amazing opportunity and responsibility to potentially change the status quo.

Through the life span of a building, an enormous amount of waste is created and disposed. The ultimate goal when planning to build a green structure is to reduce, reuse, recover, and recycle the waste in a building’s life cycle. Under current practices, valuable materials such as wood , brick, cement, metals, and glass are landfilled; this material is believed to account for approximately one-hundred million tons of waste per year in the United States. This amount equals one-quarter to one-third of the total waste generated worldwide.[iii] The large amount of waste created throughout the lifecycle of the building is an issue not only because it is taking up so much space in the landfills, but also because it is contributing to a major loss of raw materials such as wood, paper, glass, and metal. These raw materials should be recycled and maintained in the materials cycle.

It is our responsibility to choose the materials used in the building with care, not only for our own health, safety, and wellbeing, but also for the sake of future generations. When designing a new green building , it is important to set goals and to strive to achieve them.

• Renewable resources and materials that require the least amount of energy to produce and transport will be used over non-renewable resources and materials that require much energy during production and transportation. The goal is to choose materials with lower environmental impacts and reduce the amount of embodied energy consumed during the building’s entire life time.
• A second goal is to use materials, builders, construction firms, architects, and installers from local sources and companies. A large amount of energy is used in the transportation of materials and products alone; by choosing materials and services located near the building site, transportation and negative environmental impacts would be lessened (while also supporting our local economy).
• Because the health of the individuals and the nearby ecosystem are of utmost concern, materials that do not present possible health hazards will be incorporated into the building. The goal is to contribute to good indoor environmental quality (IEQ) during construction , to create and maintain an environment that is healthy and safe for all individuals during occupancy, and to not contribute to ecosystem destruction and pollution from harmful materials.
• Another goal is to decrease the amount of waste entering the landfills and the amount of raw materials being lost as waste. To accomplish this, materials that can easily be disassembled and recycled will be used. By doing this, the amount of waste polluting the earth will be reduced. Therefore, raw materials are kept in the material flow, ready and able to be used in other applications. By keeping the materials in the material flow and out of the waste chain, there is also a very large amount of energy that is being saved because new materials are not being produced.
• A final goal is also directed at the amount of waste entering the landfills. Building materials may not only generate waste in their installation and demolition, but in their production as well. The fact that many materials can generate more pollution in their production than in their entire lifespan furthers the need to choose materials that produce less waste in all three areas. The choice of greener and less wasteful materials is very important in reducing landfilling and pollution.

Achieving these goals should not only have positive environmental effects, but also positive economic ones. Many times it is actually more cost effective to recycle the waste created during construction and demolition than it is to landfill it. It costs about twenty dollars per ton to landfill construction and demolition waste.[iv] On the other hand, some metals can actually create revenue when recycled .

Many chemicals used in the production of materials can cause health problems to humans and others. Some have the potential to cause cancer while others increase the risk of causing birth defects. Oftentimes, either the materials that are used in the construction of a building are made with these hazardous chemicals or they release toxic fumes into the air we breathe, putting us at greater risk of developing serious health problems. Materials that are particularly dangerous include those that off-gas toxic, carcinogenic, mutagenic , or tetragenic materials into the environment.