1. Build what makes sense. Small is subjective.
2. Be frugal. Being frugal means being modest, not a cheapskate. Stay away from subpar materials. Be willing to pay for quality and save money by limiting your demands.
3. Reuse the right stuff. Salvaged materials can be great or utter garbage. Reuse materials that will enjoy - and deserve - a useful, long life; don't use stuff just because it's used or or cheap.
4. The construction industry has a terrible history of approving - and subsequently banning - products shown to be toxic. Most of these manufactured goods won't last as long as traditional materials like wood and stone and require intensive energy to manufacture and ship. Not all prefabricated products are equal. Investigate your inputs and know what you're putting into your house - and your body.
5. When possible - use local materials if they're of good quality.
6. When needed - hire local contractors if they do good work.
7. Create beauty! Design is one of the most important factors when it comes to sustainability. People are more likely to care for and preserve a house built with care and preservation in mind.
8. Build efficiently; build to perform efficiently. If possible, have your work tested to be sure you're achieving your goals. Verification, which tests actual performance, beats any certified checklist. In fact many certification programs, including LEED, don't even test performance and isn't worth the investment. Rather invest this money directly into your project.
9. Use the least toxic materials available.
10. Reject much of what passes for quality construction and design.
Shawn A. Dehner - THE small HOUSE CATALOG