If you are designing your own environmentally friendly home, the question you first need to ask is: "what do you want from your Eco Friendly home?". There are two main subjects to consider with your design, the first is the Building Materials you are using and the impact they have on the environment both in their development and their use, and the second is how much demand your home has on natural resources.
Lets first consider the building the materials you are choosing for your eco-friendly home: This is where you take into account the impact of using the core root materials used in the products you are using to build your eco friendly home.
Where steel is a depleting resource, timber of course is renewable, however the timber tanning process can often be harmful to the environment so you may choose mudbrick over this or look at more modern recycled alternatives
Another factor is material processing. As materials are taken from their natural environment they are often the reconstituted using toxic resins or processed or under go toxic treatments to sustain the products durability, its fire retardant properties or resistance to insects, moulds and fungi's.
Where do you draw the line? We still need an element of steel for nails and screws, and plastics for piping and other necessities, it really depends on how extreme your passion is for alternative building methods.
The second consideration and by far the most popular topic for Eco Friendly Home Designs is the demand your home has on resources. Can your home use natural lighting and heating that minimises use of electricity, in hotter environments you may be considering natural light but minimising heat from the use of natural air flow.
How much water does your home demand, are your appliances using less water, less electricity. How much can you recycle in the way of waste water, food scraps and general waste such as glass and plastics?
Now at interesting question is, "Can your home produce more energy than it consumes?" Then consider your outputs, What ablution waste services have less impact on the environment. This is more important for rural eco friendly home designs where town/city services are not mandatory.
Self sustainable eco friendly home designs create homes that take full advantage of their environment, minimising the need for artificial heating or cooling, they supply there own electricity and uses it sparingly.
They have there own water supply and storage and have gardens that produce enough produce to feed the occupants. Along with this the homes are built from renewable, biodegradable, recyclable or recycled materials.