BuildZoom, which is a tool to help people find local contractors, recently looked at construction costs across the US.
Here is their 30-city average index running from 1950 to roughly today:
Here is a chart showing the most and least expensive cities (that is, the cities that deviate the most from their 30-city average):
And here is a chart that compares labor cost appreciation to material costs:
Labor costs account for the bulk of the geographic variation in construction costs and the most expensive cities to build in also tend to have the highest median home prices.
The way to read the above chart is that any city with a y-axis value greater than 1 means that labor costs have appreciated faster than material costs from 2008 to 2017.
In the case of San Francisco, labor costs have appreciated 32.8% (> 1.3) faster than material costs.
Part of this likely has to do with the fact that San Francisco is an expensive city in which to live. People have to be paid more if they’re going to work there.
Full blog post from BuildZoom, here.