How long until they demolish my house?

This article originally appeared in the January 2018 Richmond Neighborhood Newsletter.


A major concern we hear frequently in our neighborhood forums is “when will we stop demolishing Portland?” That got me wondering, when will we run out of things to demolish? Or even more pertinently, when will my house get demolished?

To figure out the answer to this question I need two key pieces of information:

  1. How many homes are demolished per year in the neighborhood?
  2. How many homes are there in the neighborhood?

Piece 1: How many homes are demolished per year in the neighborhood?

Fortunately we live in a city that does a great job of making information readily available online. You can search the city’s main website for property-related info at www.portlandmaps.com, then select Advanced » Permits, to find the number of demolitions that have occurred in our—or any—neighborhood since about the year 2000. For the purposes of this exercise I used the data since the latest census in 2010. From the results for this search we can see that since 2010 there have been 54 demolitions of single-family residences, and 2 demolitions of triplexes; meaning that a total of 60 housing units have been demolished in the past 7.75 years.

We now have the first key piece of information we need:
On average there are 7.7 housing units demolished per year in the Richmond neighborhood.

Wow, that’s less than I expected. The poison is in the dose though, so to know how bad anything is you need to know it’s concentration.

Piece 2: How many homes are there in the neighborhood?

Now we know there are 7.7 housing units demolished every year, but in order to understand the impact of that number on our neighborhood, we need to know how many total units there are in the Richmond neighborhood This one should be easy to answer; all I have to do was find census records that break things down by neighborhood and I should have my answer.

The Office of Neighborhood Involvement (ONI) is the bureau that most likely would keep such records on hand. Doing a search online for ‘portland census oni’ quickly finds the exact data I need (https://www.portlandoregon.gov/oni/article/376015).

We now have the second key piece of information:
As of 2010 there are 5290 Housing Units in Richmond.

Great! Now I have both pieces of information I need to answer my main question…

“How long until they demolish my house?”
To determine this I divide the total number of housing units demolished by the total number of housing units. That shows me that each year only about 0.15% of the homes in our neighborhood are demolished. Not bad. But that doesn’t tell me how long until MY house is demolished. To get this answer all I need to invert the odds to find out how long the typical home will last. And how long is that? 683 years.

That means—odds are—my house won’t be demolished until the year 2700...I think I have a bit of time.