For the past year, we have been gathering and analyzing millions of building permit records, records that contain all sorts of interesting information about the projects being carried out on the country’s housing stock.
These permits generally contain the name of the builder, the address of the job, a classification of the work performed, price information, a detailed description, and more. As such, the building permits represent a unique opportunity to analyze broader trends in the nation’s real estate markets and the economy at-large.
The main challenge associated with using building permits for market analysis is the degree of variance in the structure and types of information required by different permitting authorities. We’ve overcome that by focusing our analysis on keywords in the project description field, a field required by all permitting bodies.
Our analysis of 32,000 permits containing the term “solar’ in their project description, gathered and classified from 72 municipalities, shows that for the past 10 years the average annual growth rate for solar remodeling permits has averaged over 50%. Since 2008, that exponential curve has only begun to accelerate.
For the sake of comparison, we plotted solar projects against overall remodeling activity in the BuildZoom dataset.
The distribution of estimated prices from each permit for 2012-2013 shows that photovoltaic projects are also considerably more expensive than solar thermal projects.
Over the past four years, the median price for residential photovoltaic installations has decreased while the median price for thermal solar projects has increased.
Top 10 most active states for solar projects over the past 10 years.
Contractors who have applied for the most permits over the last 10 years:
Fastest growing contractors (with a minimum of 80 projects in 2013)
To gain a better understanding of what types of contractors were benefiting most from the rapid growth in solar, we created a histogram of license classification. Here are the top four broad classifications of license type by # of solar permits.