I have a small library on folk vernacular architecture. A quickie definition of vernacular architecture is that it's the kind of architecture that people in a locale with approximately the same cultural heritage have developed. They can have been influenced by other peoples. Architecture is never static, in my opinion, but draws on itself, group philosophies, trends, and ideals. Good vernacular architecture, in my opinion, solves local climatic and energy issues and expresses the culture visually in some uniform but evolving way. It sometimes presents a unique use of local materials. Vernacular pertains to a level of do it yourself that still utilizes local expertise in craftsmanship, but does not necessarily presume the kind of formal architectural or engineering training that is generally presumptive of what we term architecture or engineering today. Vernacular speech is what local pepople use with one another to communicate in a society that still has fornal speech.
That said, there are examples where traditional and vernacular architecture come together, ex. hiring a mimar (Islamic design builder) to design one of the coral mosques of Suakin. Local materials were used (coral blocks, similar to the prehistoric shell material in St. Augustine, Florida 16th c. building), mosques and public buildings were designed but local people as home builders used the same material for residential housing. In this type fo traditional building, the building material itself is beautiful in color and unique, the material used caused the local building to become attractions, the materials used were traditional building materials from the area that promoted cool, clean, low maintenance living and worshiping. Just a tiny example. It is always wonderful to discover some native/tribal/aboriginal/modern ordinary guy and gal/ way of solving a common problem. Shelter itself is a kind of local problem. It is wonderful when people express philosophical thought through decoration in some kind of local way and solve some kind of climatic issue at the same time, like the Russian or Scandinavian stove to heat an entire dwelling efficiently (and to use whole or large pieces of logs that burn slowly to ash in the process so less energy is used even preparing fuel). I don't see discussing making one's own hummus (note that the guy who started the thread on tomato basil hummus didn't dare to post the actual ingredients of the stuff he bought...) is contrary to the discussion of good design. We choose to design what we do with our time and how we fuel everything from buildings to our own bodies. We can accept a developer McMansion, eat out and buy processed food, or we can design, collaborate in the designer or at least have impute into the needs that cause us to live live in what works and what we need while making sure that quality goes into our bodies. It's all related.
The Coral Buildings of Suakin: Islamic Architecture, Planning, Design and Domestic Arrangements in a Red Sea Port (Hardcover), the classic text:
Couple images: