I am not an expert in this field, so this is just a reflection on your inquiry. Because vuInerability is contextual, I would expect experts who do not have information about your specific context to be cautious with explicitly assigning weights to the different factors you mention. Unweighted is also a possibility.

I have found this article useful as a sobering introduction to methodological choices associated with vulnerability indexing: Jones and Andrey. 2007. Vulnerability index construction: methodological choices and their influence on identifying vulnerable neighbourhoods. Int. J. Emergency Management, Vol. 4, No. 2.

Ivar, thanks for this comment, do you have the link to download this paper?

One download site: http://inderscience.metapress.com/content/yv331783ux8v3288/

@Arash.. sure you are right because most of the conditions are locally driven