Category: Housing

Working with ZIP code data (and alternatives to using sketchy ZIP code data)

December 17, 2014 / / 5 Comments
1711 North Kimball Avenue, built 1890

This building at 1711 N Kimball no longer receives mail and the local mail carrier would mark it as vacant. After a minimum length of time the address will appear in the United States Postal Service’s vacancy dataset, provided by the federal Department of Housing and Urban Development. Photo: Gabriel X. Michael.

Working with accurate ZIP code data in your geographic publication (website or report) or demographic analysis can be problematic. The most accurate dataset – perhaps the only one that could be called reliably accurate – is one that you purchase from one of the United States Postal Service’s (USPS) authorized resellers. If you want to skip the introduction on what ZIP codes really represent, jump to “ZIP-code related datasets”.

Understanding what ZIP codes are

In other words the post office’s ZIP code data, which they use to deliver mail and not to locate people like your publication or analysis, is not free. It is also, unbeknownst to many, a dataset that lists mail carrier routes. It’s not a boundary or polygon, although many of the authorized resellers transform it into a boundary so buyers can geocode the location of their customers (retail companies might use this for customer tracking and profiling, and petition-creating websites for determining your elected officials).

The Census Bureau has its own issues using ZIP code data. For one, the ZIP code data changes as routes change and as delivery points change. Census boundaries needs to stay somewhat constant to be able to compare geographies over time, and Census tracts stay the same for a period of 10 years (between the decennial surveys).

Understanding that ZIP codes are well known (everybody has one and everybody knows theirs) and that it would be useful to present data on that level, the Bureau created “ZIP Code Tabulation Areas” (ZCTA) for the 2000 Census. They’re a collection of Census tracts that resemble a ZIP code’s area (they also often share the same 5-digit identifiers). The ZCTA and an area representing a ZIP code have a lot of overlap and can share much of the same space. ZCTA data is freely downloadable from the Census Bureau’s TIGER shapefiles website.

There’s a good discussion about what ZIP codes are and aren’t on the GIS StackExchange.

Chicago example of the problem

Here’s a real world example of the kinds of problems that ZIP code data availability and comprehension: Those working on the Chicago Health Atlas have run into this problem where they were using two different datasets: ZCTA from the Census Bureau and ZIP codes as prepared by the City of Chicago and published on their open data portal. Their solution, which is really a stopgap measure and needs further review not just by those involved in the app but by a diverse group of data experts, was to add a disclaimer that they use ZCTAs instead of the USPS’s ZIP code data.

ZIP-code related datasets

Fast forward to why I’m telling you all of this: The U.S. Department of Housing and Urban Development (HUD) has two ZIP-code based datasets that may prove useful to mappers and researchers.

1. ZIP code crosswalk files

This is a collection of eight datasets that link a level of Census geography to ZIP codes (and the reverse). The most useful to me is ZIP to Census tract. This dataset tells you in which ZIP code a Census tract lies (including if it spans multiple ZIP codes). HUD is using data from the USPS to create this.

The dataset is documented well on their website and updated quarterly, going back to 2010. The most recent file comes as a 12 MB Excel spreadsheet.

2. Vacant addresses

The USPS employs thousands of mail carriers to delivery things to the millions of households across the country, and they keep track of when the mail carrier cannot delivery something because no one lives in the apartment or house anymore. The address vacancy data tells you the following characteristics at the Census tract level:

  • total number of addresses the USPS knows about
  • number of addresses on urban routes to which the mail carrier hasn’t been able to delivery for 90 days and longer
  • “no-stat” addresses: undeliverable rural addresses, places under construction, urban addresses unlikely to be active

You must register to download the vacant addresses data and be a governmental entity or non-profit organization*, per the agreement** HUD has with USPS. Learn more and download the vacancy data which they update quarterly.

Tina Fassett Smith is a researcher at DePaul University’s Institute of Housing Studies and reviewed part of this blog post. She stresses to readers to ignore the “no-stat” addresses in the USPS’s vacancy dataset. She said that research by her and her colleagues at the IHS concluded this section of the data is unreliable. Tina also said that the methodology mail carriers use to identify vacant addresses and places under change (construction or demolition) isn’t made public and that mail carriers have an incentive to collect the data instead of being compensated normally. Tina further explained the issues with no-stat.

We have seen instances of a relationship between the number of P.O. boxes (i.e., the presence of a post office) and the number of no-stats in an area. This is one reason we took it off of the IHS Data Portal. We have not found it to be a useful data set for better understanding neighborhoods or housing markets.

The Institute of Housing Studies provides vacancy data on their portal for those who don’t want to bother with the HUD sign-up process to obtain it.

* It appears that HUD doesn’t verify your eligibility.

** This agreement also states that one can only use the vacancy data for the “stated purpose”: “measuring and forecasting neighborhood changes, assessing neighborhood needs, and measuring/assessing the various HUD programs in which Users are involved”.

Proposed residential high-rise injects TOD and population loss into Logan Square conversation

October 31, 2014 / / 0 Comments
A public notice stands in front of an affected property

There used to be a Max Gerber plumbing supply store here that the absent landlord demolished to reduce his property taxes. A developer has proposed built 254 units in two towers here, in spitting distance from the CTA’s 24-hour Blue Line.

Developer Rob Buono has proposed two towers for a vacant property 400 feet away (walking distance) from the Chicago Transit Authority’s California Blue Line station. It has caused quite a stir in Logan Square about how much development is the right amount, and brings into question residents’ understanding of how the neighborhood demographics have changed.

It has also brought “TOD” into the local conversation. Buono will get some relief from exceptional car parking requirements because of the land’s proximity to the ‘L’ rapid transit station.

The process will be a long one. The first meeting, called by Alderman Moreno, was held on Thursday night. I counted over 70 people on the sign-in sheet when I came in, and many people arrive after so saying 100 people were there isn’t a stretch. Moreno described his development policy: whenever they need a zoning change they must present their proposal to the community so Moreno can get their feedback.

Before Buono spoke, though, Moreno asked Daniel Hertz to briefly talk about transit-oriented development and why the development (or at least the number of units and car parking spaces it proposes) is a good project for this place, and in this neighborhood. In balancing concerns about car traffic, keeping people close to the services and products they need, and making it easy to get around, it makes the most sense to put the highest number of housing units in close proximity to high-capacity transit versus anywhere else.

Essentially, Logan Square has lost residents – 10,000 people since 2000 – concentrating the burden of patronizing local businesses, seen as a distinguishing asset in the neighborhood, on fewer people. Additionally, adding housing is the best way to combat rising home prices (and unaffordable rents) by offering more supply which reduces demand on richer people buying, converting, or tearing down existing buildings.

While no building permits will be issued for the towers until Ald. Moreno, Plan Commission, and City Council approve the zoning change, you can track what other kinds of buildings developers are building in the area surrounding 2293 N Milwaukee on Chicago Cityscape.

You’ll see quickly that a majority of the projects permitted this year are for single-family houses. Some of these are built on vacant parcels while at least one is  being built where there was previously a multi-family house.

In 2014, within 1/8 mile of the site:

  • +0 units in multi-unit buildings
  • -1 deconversion, turning two units into one unit
  • -1 teardown, turning a two-unit property into a single-family property
  • +17 single-familiy homes
  • Net gain of a maximum of 15 units

At this rate, Logan Square may grow at an extremely low rate – these homes will likely be filled with small families. The decreasing household size is another factor in Logan Square’s population loss.

Read about people’s reactions to the towers on other sites:

Joe Moreno

1st Ward Alderman Proco “Joe” Moreno gracefully – given the circumstances – moderates the meeting.

What modernism should we preserve?

March 7, 2013 / / 0 Comments

Ed. note: This post is written by Ryan Lakes, friend and architect. 

Goldberg’s Marina City towers are a couple of my favorite buildings in Chicago, but all of the discussion about preserving Prentice Women’s Hospital – designed by Bertrand Goldberg – has left me conflicted. The following is my response to the video above that was originally posted on Black Spectacles.

When we figure out how to easily move old, significant buildings that are no longer wanted by their owners and occupants, to museum-cities made up of the old masterpieces that have since fallen out of use or favor, then we will have the luxury to preserve them like books, paintings and sculptures. To me, large buildings are more like trees than art. Occasionally the great old fall to make way for the young. There is no moving them. And as time passes, individual systems age and decay, and evolution leads to new, often more efficient ways to compete for space and resources.

Prentice Women’s Hospital is slated for destruction by its owner, Northwestern University. Photo by Jeff Zoline. 

Contemporary architecture has a new set of more complex criteria to respond to than what was included in original modernism’s scope. With form ever following function, in modernism, as functions change, so too shall the forms. Is modern architecture able to do so? How do fans of modernist buildings plan to preserve them as fuel prices rise and the desire for energy efficient buildings increases?  What else besides their structure is not obsolete? Let’s not forget that the time of modernism was when most thought our resources were unlimited, that it was better to leave our lights on 24 hrs a day to save bulbs, and that it was better to employ machines to fabricate our buildings rather than our neighborhood craftsmen.

Photo of Zurich Esposito at protest to save Prentice by David Schalliol. 

Evidence of “Olympic change” in Rio’s favelas

May 16, 2011 / / 0 Comments

I have never read Al Jazeera’s English edition until yesterday. I think I saw a post to this article on Twitter; it’s about how construction for the Olympic games in Rio de Janeiro, Rio, Brasil, is already removing parts of the favelas, or hillside shantytowns. The article is quite relevant for me because I wrote last week about how rising ticket prices threaten the egalitarian nature of watching futebol at the Rio’s most famous stadium, the Maracanã. From Al Jazeera:

This week came a series of troubling tales of the bulldozing and cleansing of the favelas, all in the name of “making Brazil ready for the Games”. Hundreds of families from Favela de Metro find themselves living on rubble with nowhere to go after a pitiless housing demolition by Brazilian authorities. By bulldozing homes before families had the chance to find new housing or be “relocated”, the government is in flagrant violation of the most basic concepts of human rights.

As you might expect, residents and planners have different ideas on what it means to remove these homes:

[Eduardo] Freitas doesn’t need a masters from the University of Chicago to understand what is happening. “The World Cup is on its way and they want this area. I think it is inhumane,” he said.

The Rio housing authority says that this is all in the name of “development” and by refurbishing the area, they are offering the favela dwellers, “dignity”.

The same thing has happened all across the United States and is still happening in Chicago. The Chicago Housing Authority, very quickly in the past 10 years, has demolished all of its high-rises (some were converted to condominiums, like Raymond Hilliard Homes at 54 W Cermak, or transferred to different ownership) under the Plan for Transformation. This displaced thousands of residents; some were moved to newly-built multi-flat buildings in specially-designed, mixed-income neighborhoods. But there weren’t enough of these buildings to absorb all of the residents who had to move out of the high-rises. I’m still not clear on where they went.

A favela in Rio de Janeiro. Photo by Kevin Jones.

Chicago’s final public housing high-rise was demolished in April 2011.

World Cup and Olympics construction will disadvantage Rio’s poor

May 9, 2011 / / 0 Comments

It is a scene we see every four years when the Olympics come around: Development that displaces a group of people who lack a good defense, unlike the futebol team they used to pay $1.80 to see.

There used to be a standing-room only general admission area in the Maracanã stadium in Rio de Janeiro, Brasil, years ago, but no longer exists today, according to an article yesterday in the New York Times. (Rio will host the 2016 Olympics after beating Tokyo, Madrid, and Chicago.)

The price of tickets is important to cariocas (residents of Rio) because of the stadium’s “role as an egalitarian space in a heavily unequal city like Rio.”

“What could be lost is the nature of the stadium experience as something that cuts across the class segregation of the city as a whole,” Bruno Carvalho said, a Rio native who is an assistant professor of Brasilian studies at Princeton. “Do you give up the vitality of the Maracanã as a public space, a rare type of space in Rio where you can actually get together people of different social classes?”

Members of the National Fans Association understand that safety and comfort upgrades, for which the general admission area was removed, have to be made for an event such as the World Cup 2014, but they want to ensure that other venues under construction be integrated and their designers consult local urban planners and neighborhood groups.

Nine new venues will be constructed for the Rio Olympic Games, and seven venues will be constructed but removed after the closing ceremony. For the 2008 Beijing Olympics, thousands of city residents were “relocated.” Some reports say 15,000 moved voluntarily with compensation and another says 300,000 were evicted.

I have a concern that in the next five years, there will be founded accusations of cariocas’ civil rights as “progress” pushes them out of the way.

Photo of the Maracanã stadium by Phil Whitehouse.