Posted on August 1, 2018
By Tom Hopper
A few weeks back, the Globe published an article by Tim Logan on the relationship between job creation and housing development in the city of Waltham. The thrust of the article is that while Waltham has added a staggering number of jobs (11,000 between 2010 and 2016), the city’s housing production has not kept pace. Workers need places to live, so these new Waltham workers are unlikely to find sufficient housing in the city in which they work. The piece provides a great example of the general disconnectedness we see between economic growth and housing production all across the state.
Reading through Tim Logan’s article, the following paragraph caught the attention of our staff at the Center for Housing Data:
“During the same period those thousands of jobs were being created, the city of 63,000 people – up 3 percent from 2010 – added just a few hundred homes, most of them in two downtown apartment buildings.”
What struck us about this statement is the lack of precision in the number of housing units produced. If we can measure the number of jobs created, how come we can’t get an exact count of the housing units produced in the same time period? Well, it turns out that measuring housing production is actually a pretty difficult task in Massachusetts, particularly because housing decisions are made independently by 351 cities and towns with 351 independent permitting and approval processes. Without an Office of State Planning, there aren’t a whole lot of options for routinely compiling and analyzing these disparate data sources on new production.
But investigating data is what we do, and we saw this as an opportunity to dig a little deeper to see if we could provide a more detailed estimate of the number of units produced in Waltham since 2010. Here we go.
The first stop on the data train was the Building Permit Survey, compiled by the U.S. Census Bureau with help in Massachusetts from the State Data Center, run out of UMass Donahue. According to this dataset, Waltham permitted roughly 525 net new housing units from 2010-2016. This includes a huge spike in permitting in 2013, the result of one multifamily building with roughly 200 units.
The Building Permit Survey data is easily accessible, but it comes with some caveats that impact its reliability and accuracy. One issue is that the data is self-reported by individual towns, and reporting frequency is often less than ideal. Waltham has, for many years, been a fairly good reporter. In the years 2010-2014, Waltham provided complete information. However, in 2015 only 6 months of permits were reported, and in 2016 the city did not report at all. What happens when reporting is not received? I still have more to learn on this topic, but my very basic understanding is that missing data are imputed by the census bureau based on a combination of factors, including past permitting history of the community, as well as the rate of change in regional permitting totals (feel free to write me and correct this). Needless to say, an imputed count is not as good as an actual count, and it calls into question the accuracy of the 2015 and 2016 numbers from the charts above.
Another issue with the Building Permit Survey is that even when reporting is good, we can’t tell for sure if the municipality is reporting correctly. Through our work over the past year or so with this dataset, we have found that it is not uncommon for actual counts of new units to differ from those reported on the Building Permit Survey. One prime example has to do with demolitions. The Building Permit Survey methodology requires respondents to report net new units, basically all newly built units minus any units that were demolished. However, in many places, Building Permit Survey reporting is not a high priority task, and this methodology is not always followed perfectly.
Additionally, this dataset includes permitted units, which is different than built units. While our sense here at MHP is that most permitted units do eventually get built, there is definitely a lag between when a permit is issued and when a unit is built. What we are trying to sort out here is how many new units have come online.
So, although the Building Permit Survey is easily accessible, it leaves us wanting for another way to verify housing production levels. Luckily, we found one. The second stop on our data route comes from the town’s assessing department. MassGIS collects, helps standardize, and compiles tax parcel map files for every city and town in Massachusetts (except Boston, which provides public access to its parcel files separately). Waltham sent an updated parcel map to MassGIS in 2017, so we have a pretty current file to work with. These files provide a wealth of information on the parcel level, including the property’s use (residential, commercial, industrial, etc), as well as more detailed information such as number of stories, owner information, year built, and number of units. This just the information we need for our exploration. So, we popped the data into GIS and did some digging. First, we isolated all of the residential use parcels that have been built since 2010. Here they are: