Most people today, will be at least some what concerned with the environment, when planning and building their home. Both construction and the ongoing operation of the house will have their effect.
The size of your home will have the biggest overall impact. If the environment is a primary concern of yours, carefully consider your needs, and build as small as you are comfortable with. This has added advantages in cost, and in future maintenance. There is much less effort, and cost, involved in keeping a small house clean and well maintained.
The material used, in building your home, will have varying costs to the environment. Although I lack the resources to be specific, I can list some concerns to be considered.
Reuse and recycling of material should be considered at every opportunity. The longevity of materials is important, as it reduces waste streams. Fuel use for transportation is also an important factor.
Wood is used extensively in housing and furnishings. It is a natural and renewable resource. Carbon is stored in the wood for the life of the house. Replanted forests remove carbon dioxide from the air and stores it in the wood. Some carbon is transferred to the soil in the form of humus. The cost would be in the energy used for harvesting, transportation and replanting, and in land use. Recycling and reuse is limited.
Concrete is another common construction material. It’s longevity is excellent. Because of weight, transportation is a significant factor. The ingredients, though abundant, must be mined. The limestone used for cement must be heated in kilns to drive out the water. The carbon release to the atmosphere is significant. Concrete is not easily reused or recycled.
Steel, and other metals used, must be mined and refined. Many metals are becoming harder to find and increasingly costly to mine. This usually has significant effect on the environment. On the other hand, metals are relatively easy and economical to recycle, and a high percentage of metal products are from recycled material. Metal products used in house construction have excellent longevity.
Plastics are being used more and more in home construction. It is replacing metal almost totally in plumbing. It is also widely used for window manufacture, vapor barriers, insulation and fixtures. Plastic has a bad reputation in the waste stream. It is almost indestructible and recycling is not yet widespread. This relates largely to it’s use for packaging and for disposable containers. It’s use in housing does not contribute greatly to this problem. Plastics are commonly made from petroleum resources such as oil or natural gas or their by-products. It’s light weight and longevity reduces it’s impact on the environment when used in construction.
Glass is a component of every home. It can be reused but is seldom recycled. An inert material, it is virtually indistinguishable from normal soil components, if crushed. Energy is used in it’s manufacture, and it’s weight adds to transportation cost. Glass fiber has widespread use as insulation, in shingles, and as a structural component of doors and fixtures.
Brick, tile and other ceramic material use considerable energy in their manufacture and they are heavy. Sun dried adobe is usable in some climates, and has less impact.
Asphalt, used in shingles or for driveways, requires some heat to remain liquid until used. The name is applied to the material used for roadways, even though gravel and sand are the main components. The same is true for shingles, where other materials make up the bulk of the mix. Recycling is possible where facilities or equipment exists. Transportation is a large factor in the economies of recycling. A petroleum by-product, asphalt may be a more finite resource than concrete, but likely creates less greenhouse gas in it’s production.
Some materials, such as stone, earth, straw bales, or in some cases wood, have very little negative impact on the environment. If they are available locally or even on site.
Transportation of material is often the largest single source of pollution and greenhouse gases. The use of locally produced material can significantly reduce the impact of your project.
The longer the useful life of a construction material, the less it will effect the environment. Single use items, such as packaging and disposable containers, create huge problems in disposal. The near indestructible properties of plastics make them an excellent choice in construction, but the same characteristic is a problem when they are disposed of. Recycling helps to alleviate the problem, but faces problems of economics and logistics. Transportation of waste to recycling plants may cause more pollution than it alleviates.
Asphalt shingles are a good example. They are available in grades with life expectancies of from 20 to 50 years. Because the initial cost of a house is important for many reasons, builders often use the lowest grade, even though the long term economics strongly favor longer lasting products. Twice the lifespan means half the material use and half the contribution to the waste stream. Used shingles are usually sent to a land fill because of a lack of recycling facilities.
The ongoing operation of your home also has significant impact. Comfort and economics strongly favor an energy efficient home up to a point of diminishing returns. Current low interest rates, and rapidly rising energy costs, means more capital investment can be made in efficiency. Reducing the size of your home, to closely match your actual needs, can also make more money available. Your concern for the environment may trump pure economics, but don’t forget the impact of material use. The energy used to manufacture and transport material could negate any future energy savings.