Greener Building Materials and Construction Techniques
Fly-Ash: The recent trend is to use "fly-ash," which is a residue from coal fired power-plants. These are used in the making of cement. Usage of fly-ash decreases the cost of the concrete and results in a higher quality product. When cement is produced, huge quantities of carbon-dioxide are released, and this results in air and water pollution. Usage of this residue will lessen GHG. Bamboo: Often misunderstood as a light, slender wood, bamboo is lighter than steel, but five times stronger than concrete. It absorbs four times more carbon-dioxide than most trees. It can grow faster than any normal tree (usually several feet/day), and has a great cooling effect too. Certain parts of southeast Asia have houses made of bamboo, and there is no problem in using it except for the problem of joining two bamboo sticks together. The main positive aspect is that it is a renewable source.
Evaporative Cooling: This cooling technique is used in plenty of places near the tropics. It is very similar to the production of sweat from our body. As we feel the heat, our body produces sweat to cool itself. In the same way, the water content in the plant evaporates, taking away the heat from the surrounding air or the atmosphere, thus making it cooler. It is also very similar to the cooling effect that is produced when a drop of alcohol is held in our hand. The alcohol vaporizes taking away the heat. This cooling effect is known as "green roofs."
Straw bales: They can be used as a main structural component or as a soft insulation. These are packed as closely as possible and made hard so they can withstand considerable amount of load and impact. One may think that these straw bales are a fire hazard, but they are not. They provide three times more fire resistance than conventional homes.
Earthen Rocks: The main property of earthen rocks is "thermal mass." These rocks posses a high degree of thermal mass thus can be a better substitute for insulation. Insulation may sometimes be made of toxic material or harmful material, but these rocks are natural and are eco-friendly. So thermal mass is the property to absorb, store, and release heat energy. These are best suited for desert climates.