Use Natural and Recycled Materials
For a truly Green Passive Solar Home, consider using natural, local or recycled materials as the main ingredient in your building. Earth and straw are building materials that have been used in homes for thousands of years. They are cheap and readily available locally almost anywhere. If you use earth as your construction material, it should be composed of approximately 70 percent sand and 30 percent clay; most of the dirt in most parts of the world is appropriate for building. There are many different methods of constructing with earth. Cob is a simple, labor-intensive method of building with earth: simply mix the earth with straw and water and then take handfuls of the mixture and pile them on top of each other by hand to create your structure. Building with adobe is similar; you mix the earth with water and then form it into bricks which you can stack to create a building. Rammed earth uses the s ame mixture of clay and water, but instead of piling or stacking, you compress or tamp the earth into place. In modern buildings, rammed earth is made with machines. All earth buildings are very durable; if constructed properly, they can last for thousands of years. They can also easily be built to be highly energy efficient since earth has such a high thermal mass.
Straw bale is another cheap natural material that can form the basic construction material for a natural, green home. In this method, bales of straw form the bulk of the walls inside a standard wood frame. This creates excellent insulation and is quick and easy to construct. However, the straw needs to be plastered over to prevent moisture or pests from getting into it, and because this is a specialized skill, it can be expensive to have a straw bale house finished.
You can also build a house out of recycled materials. Michael Reynolds of Earthship Biotecture invented the concept of "earthships," which are houses built out of used tires and aluminum cans on wood frames.
Do the Work Yourself
Many ecologically sustainable constructions are more labor-intensive than they are skill-intensive. Even for a house that requires special skills, such as a straw bale house, you can save money by doing much of the labor yourself. By acting as general contractor for your home, you can not only save money, you can also be truly involved in a hands-on way in the planning and design of your home. Traditional cob building, for example, involves mixing the earth and straw with bare feet and then piling the cobs by hand. This might sound like a tedious process, but when done together with a group of friends or family who all participate in the design of the home as well as its construction, it can be a fun and exciting project.
Build for Efficiency and Sustainability