People in most parts of the world have lived in one place for generations and have learned to make the best possible use of locally available materials and to cope with their own climatic conditions. Sometimes, an outsider can inject a new thought or design element to make things better but, on the whole, they've got their system pretty well worked out. They know, for instance, where the rain comes from or the wind. They know from experience which areas are prone to landslides or forest fires. They'll often even tell you which trees grow well and which won't - no matter how hard you try.

When you're an architect designing something in an area that is new to you, it is wise to take this collective locally knowledge into account. Of course you need to supplement it with hard data from the weather bureau - if such data exists - and you are bound to carry in your own personal way of designing to create a unique structure. But, at the end of the day, it's an extremely useful resource to have.

Local material is relatively cheaper than what you might import from far away (not to mention the fossil fuel burned up in transportation). Also, if you're planning on using local labour (and why not?), their familiarity with it leads to a sturdier and better finished project.