Green Construction

A Guest blog by Krista Peterson

Green construction is a new form of construction that is safer for people and the environment and is cheaper over the long term than old construction. Its use follows an era in which residential and commercial buildings were constructed both cheaply and quickly to please owners. Instead of focusing on quality, the goal was most certainly quantity. The materials used in the building of these shoddy and quickly-constructed structures were typically very unfriendly to the environment and contained hazardous products including fibrous asbestos¹.

Fibrous asbestos is the only known cause of the disease mesothelioma, which is a rare form of cancer that affects the linings of the heart, chest and abdomen. When asbestos fibers become airborne they can be inhaled or consumed – via eating or drinking – and they will eventually cause a variety of harmful and fatal health problems. Mesothelioma symptoms often resemble the common cold and other basic chest and lung ailments, which makes the victims life expectancy substantially shorter because of the common misdiagnosis.
Asbestos was used in more than 3,000 products during the 20^th century, as it was inexpensive and present in large quantities. Perhaps the most common use of asbestos was for insulation. Fortunately, construction workers can now use safer choices to insulate a building. These include:
1. Cotton Fibers – A highly popular material used in the construction of “green” buildings, insulation made of cotton fiber is made using denim and other forms of batted recycled material. As with cellulose, cotton fiber is treated using mild chemicals to make the material fireproof. However, the fiber is completely nontoxic and does not produce any gases.
2. Cellulose – Formed from 85% recycled material, cellulose is a fancy way of defining old shredded newspaper. This material has quickly become one of the most popular forms of eco-friendly insulation throughout the world. The cellulose is treated using safe chemicals to increase its resistance to heat and to prevent growth of mold. It is completely nontoxic and has been shown to decrease utility bills by as much as 20% annually.
3. SPF or Spray Polyurethane Foam – This type of insulation is ideal for those who suffer from allergies as it is sprayed within the areas that need to be insulated. The foam fits very snugly and does not allow mold to grow. These are several different types of foams that are sold but it is agreed that water-based icynene is the best. It contains no polybrominated diphenyl ether that is toxic. This type of foam also lacks hydrochlorofluorocarbons that are greenhouse gases and can catalyze the destruction of stratospheric ozone. On average, the use of SPFs can decrease utility bills by around 35%.

Other substances that were toxic were also used in building construction, which would affect both the health of those who were working to construct the site and those who worked in or resided in the building. Fortunately, the dawn of the 21st century brought many different options when it came to replacing these old products that were used and proven hazardous to human health. These replacements greatly improved the indoor air quality and the general environment for working and living conditions. Additionally, buildings that were well-constructed and were built to be environmentally friendly typically needed less energy to function and consumed less water. This saved environmental resources, and pleased tenants and landlords as the costs of water and electricity were decreased. Thus, green construction is smart construction because it is healthier, eco-friendly, and in the long term more cost-effective than conventional construction.

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1. Asbestos is a family of six minerals. The fibrous amphibole forms (amosite, crocidolite, anthophyllite, tremolite, and actinolite) are known to be carcinogenic. However, the cancer risk presented by the most commonly used form of asbestos, chrysotile, is low or nonexistent; see Ross (1984) Definitions for Asbestos and Other Health-related Silicates, American Society for Testing Materials Special Publication 834, pp. 51-104.

Collect and Purify Water

During short- and long-term emergencies, the most critical resource for you and your family will probably be potable water, especially if you live in an arid region. To prepare for such emergencies, and also to conserve water, you can practice rainwater harvesting.  Rainwater harvesting is one of the easiest ways to move towards self-sufficiency. Because we need water to survive, it is important not to rely completely on the system to provide it; redundancy is desirable in critical life-support systems such as water supply [1].

Because evaporation purifies water, rainwater is usually the purest water in the hydrologic cycle; you can therefore use it to water gardens without treatment. The simplest solution is to place a rain barrel (usually a 55-gallon drum with a valve) underneath the downspout of a rain gutter; the barrel should be placed as high as possible, keeping in mind that any support structure such as a stack of cinder blocks must be able to withstand the 450 pounds of a full barrel. Connect a hose to the valve and place it in your garden. The greater the height difference between the rain barrel valve and the hose outlet in the garden, the greater the pressure that drives the flow, and therefore the faster the water will come out of the hose. Rain barrels should have screens at the top to prevent debris or animals from entering the barrel [2]. Detains on how to construct a rainbarrel are given in [1], or you can purchase one prefabricated.

If during an emergency bottled or municipal tap water are not available and you plan to use rainwater for drinking or food preparation, you will need to go through some extra steps to make sure the water is not contaminated. Waterborne diseases cause nearly 15 million deaths each year. Disinfection kills the pathogens (bacteria, protozoa, parasites, and viruses) that can cause disease. Sterilization kills all living organisms in the water, bad or good. Purification removes potentially harmful chemicals in the water. A simple example makes the distinctions clear. You can disinfect water by pasteurizing it, which requires heating it to 149°F (65°C) for six to twenty minutes ([3], pg. 174). To sterilize the water, simply heat it to a hard boil in a covered pot. Boiling the water requires more energy for heating than pasteurization, but you can reduce the amount of energy required by tightly covering the pot to reduce heat loss. Pasteurization and boiling kill pathogens but do not remove dissolved chemicals such as the salts in seawater. To purify the water, you can remove the dissolved chemicals by boiling the water in an uncovered pot and collecting the condensed steam. Again, this is a very energy-intensive process. Below we will look at a few safe alternatives that require less energy.

The first step in water purification is to filter out suspended sediments that can hold chemical and biological contaminants by forcing the water through clean cheesecloth [2] or by temporarily placing the turbid water in a container to let the sediment settle out. Next, you need to remove biological contaminants that can cause disease. Boiling for ten minutes is the easiest solution. However, if you don't have enough fuel to treat all of your water this way, a more energy-efficient method is to use solar disinfection, termed SODIS ([1], [3]). Ultraviolet light kills the pathogens, and becomes more effective at high temperatures. Simply fix some shelves to a piece of metal painted black, then place bottles filled with water on the shelves and expose them to sunlight for six hours. You can paint the back of the bottles black so they will more effectively absorb sunlight and heat up to higher temperatures, killing the pathogens in as little as one hour [1]. In emergencies or while backpacking you can use iodine tablets, tincture of iodine 2%, betadine, or chlorine bleach to chemically treat water; see Lundin [3] and many other sources for detailed instructions on how to do this safely. There are other ways to kill pathogens, but most of them use high-tech devices such as UV lamps that need to periodically replaced or require electricity and are therefore unsustainable.

After filtering the water and killing the pathogens, most water will be safe to drink. For example, collected rainwater generally has very low concentrations of chemical contaminants, so it usually does not need to be treated to remove them. This is fortunate because it is much more difficult to remove dissolved inorganic chemicals from water. However, if you have reason to believe that your water contains chemical contaminants, you can use sunlight to evaporate the water and then collect the purified condensed water, a form of solar "still" ([4] pg. 471). The Watercone has an ingenious design that allows it to purify 1.6 quarts per day; it can even desalinate seawater ([5], pp. 193-4); see http://www.mage-watermanagement.com/. Or you can set up a still to collect steam produced by boiling water, as described above.

Following the simple procedures described above can help you provide potable water for you and your family during short- and long-term emergencies.

1. Kellogg, S. and S. Pettigrew, Toolbox for Sustainable City Living. 2008, Cambridge, MA: South End Press. 241

2. Bates, A., The Post-Petroleum Survival Guide and Cookbook: Recipes for Changing Times. 2006: New Society Publishers. 236 978-0-86571-568-4.

3. Lundin, C., When All Hell Breaks Loose: Stuff You Need to Survive When Disaster Strikes. 2007, Layton, Utah: Gibbs Smith. 449

4. Tawrell, P., Camping & Wilderness Survival. Second ed. 2006, Lebanon, New Hampshire: Paul Tawrell. 1080 978-0-9740820-2-8.

5. Steffen, A., ed. World Changing: A User's Guide for the 21st Century. 2006, Abrams: New York, NY. 596.