Arlington 2020: the Cost of Low-Density Housing

This is the second in a series of “Arlington 2020” articles. The first article looked at the number of one-, two-, and three-family homes and condominiums in Arlington, and how that housing stock has changed over time. This article will examine changes in the value of those properties. We’re going to look at “value” through the lens of property assessments, so we should start with an explanation of what property assessments are and how they’re used.

A property assessment is simply the Town Assessor’s best estimate of what a property is worth, based on market values. The assessor’s office inspects properties every ten years; during intervening years, assessments are adjusted based on sale prices of similar homes in a given tax neighborhood. For all practical purposes, assessed values tend to trail market values by two years. In my neighborhood, property assessments are spot on — my house was assessed at $501,000 in 2020; during 2018, sales of similar homes in the neighborhood ranged from $495,000 to $520,000.

Condominiums have a single assessed value, which includes land and buildings. Otherwise, assessed values are broken down into land value, building value, and yard items (e.g., a garage or a shed).

Assessed values are used to determine the tax rate. The assessors page on the town website has calculations in worksheet form, but for all practical purposes, it’s just a division problem. One takes the total tax levy and divides by the sum of all property assessments (in thousands of dollars), and that’s the tax rate. An individual’s taxes are the assessed value of their property (in thousands of dollars) multiplied by the tax rate. If an individual owns (say) 1% of the assessed value in town, that individual will pay 1% of the property tax levy.

The main point is that assessed values are based on market values, but with a two-year lag. Consequently, we can use them as a way to see how home prices have changed over time.

With that background information out of the way, we can look at some numbers. Here’s a graph of the median assessed values for condominiums, one-family, two-family, and three-family homes from 2013 through 2020. (the “median” is a value such that half of the assessments are above, and half are below).

Graph of Median assesed values by year and housing type
yearCondominiumSingle FamilyTwo-familyThree-family
2013$297,800$472,850$532,650$581,600
2014$300,150$484,400$530,000$574,800
2015$318,200$507,900$572,000$616,300
2016$351,050$546,300$623,150$673,550
2017$357,750$581,200$663,900$714,800
2018$395,400$618,800$732,100$787,600
2019$463,250$701,550$851,200$897,500
2020$473,100$771,900$944,000$1,010,850
%change58.87%63.24%77.23%73.81%

As one would expect, two-family homes are worth more than single-family, and three-family are worth more than two. Condominiums have a lot of variety; they could be half of a duplex, or a single unit in an apartment building. But a general upward trend is clearly evident.

These values are straight out of the assessor’s database, and not adjusted for inflation. The Bureau of Labor Statistic’s inflation calculator shows 12% inflation between 2013 and 2020; the %change is pretty considerable, even if one deducts 12% for inflation.

Next, I’d like to dig further into the 1–3 family assessments, by breaking them down into the value of land vs the value of buildings, and showing how that’s changed over time.

Single-family homes:

Graph of Land and building cost for single family homes, by year.
yearLand valueBuilding valueTotal assessed value
2013$243,700$226,300$472,850
2014$253,750$227,050$484,450
2015$272,700$229,900$507,900
2016$296,400$243,950$546,400
2017$326,400$246,400$581,250
2018$360,900$248,100$618,800
2019$440,400$250,400$701,600
2020$448,600$316,300$771,900
%change84.08%39.77%63.24%

Two-family homes:

Median land and building cost for two-family homes, by year
yearLand valueBuilding valueTotal assessed value
2013$202,500$320,550$532,650
2014$212,250$307,800$530,000
2015$256,400$309,800$572,000
2016$262,500$349,400$623,150
2017$307,000$350,700$663,900
2018$352,500$373,900$732,100
2019$478,300$374,850$851,700
2020$454,500$486,100$944,000
%change124.44%51.65%77.23%

Three-family homes:

Median land and building cost for three-family homes, by year
yearLand valueBuilding valueTotal assessed value
2013$200,100$377,900$581,600
2014$209,100$364,100$574,800
2015$249,800$366,550$616,300
2016$259,950$412,350$673,550
2017$298,100$412,500$714,800
2018$343,050$438,800$787,600
2019$459,000$440,100$897,500
2020$440,100$578,450$1,010,850
%change119.94%53.07%73.81%

There are several things worth pointing out in these breakdowns.

First, note that the land and building values “jump” a bit between 2019–2020. 2020 was one of our full reassessment years, so I’m willing to attribute this to a periodic course correction. The total increase is generally linear, but the land/building composition has changed.

Second, the median land value for single-family homes is higher than the median building value, for all years between 2013–2020.

Third, most of the increases come from changes in land value. I believe this comes down to location, location, and location. Arlington has a well-respected public school system, and it’s close to universities and tech centers is Cambridge and Boston, and office parks in Lexington, Waltham, and Burlington. City amenities are close at hand.

So what does one do about our rising home prices, and in particular, the rising value of land? The first (and perhaps default) answer is to do nothing. Rising property values are a boon to homeowners who purchased a capital asset (i.e., a house) in the past, and have seen its value appreciate over time. The downside of doing nothing is that each year, increasing housing prices create an ever-increasing income threshold for new residents.

An alternative approach would be to allow more (and smaller) units to be built on each lot. This requires reconstruction or redevelopment, but it allows the cost of land to be amortized among several households. More units/lot means more people and more density, but it reduces the income threshold for buying in to Arlington. (Note that the per-unit cost for three-family homes is lower than the per-unit cost for two-family homes. Similarly, the per-unit cost for two-family homes is lower than the cost of a single-family home).

A third article will look at the distribution of housing prices in Arlington, and how the distribution varies by housing type.

Here is a spreadsheet of data shown in this post.

Myths & Facts About Affordable Housing & Density

This timely report on the question of affordable housing vs. density comes from the California Dept. of Housing & Community Development and mirrors the situation in the region surrounding Arlington MA.

Housing production has not kept up with job and household growth.   The location and type of new housing does not meet the needs of many new house- holds. As a result, only one in five households can afford a typical home, overcrowding doubled in the 1990’s, and too many households pay more than they can afford for their housing.

Myth #1
High-density housing is affordable housing; affordable
housing is high-density housing.
Fact #1
Not all high density housing is affordable to low-income families.

Myth #2
High-density and affordable housing will cause too much traffic.
Fact #2
People who live in affordable housing own fewer cars and
drive less.

Myth #3
High-density development strains public services and
infrastructure.
Fact #3
Compact development offers greater efficiency in use of
public services and infrastructure.

Myth #4
People who live in high-density and affordable housing
won’t fit into my neighborhood.
Fact #4
People who need affordable housing already live and work
in your community.

Myth #5
Affordable housing reduces property values.
Fact #5
No study in California has ever shown that affordable
housing developments reduce property values.

Myth #6
Residents of affordable housing move too often to be stable
community members.
Fact #6
When rents are guaranteed to remain stable, tenants
move less often.

Myth #7
High-density and affordable housing undermine community
character.
Fact #7
New affordable and high-density housing can always be
designed to fit into existing communities.

Myth #8
High-density and affordable housing increase crime.
Fact #8
The design and use of public spaces has a far more
significant affect on crime than density or income levels.

See an example of a “case study” of two affordable housing developments in Irvine CA, San Marcos at 64 units per acre.

Affordable housing: San Marcos Apartments, Irvine CA, 64 units/ acre

San Paulo at 25 units per acre.

Affordable housing at San Paulo apartments, Irvine CA, 25 units/ acre.

Both are designed to blend with nearby homes.

The Gentrification of Arlington

(Comments presented to the Arlington Redevelopment Board and Select Board during a public hearing on Jan 13, 2020)

Steve Revilak, 111 Sunnyside Ave. In the interest of disclosure, I live in market rate housing that was built by a developer. Among Arlington residents, I’m not unusual in that regard.

At the end of December, a friend sent me an article that appeared on Redfin’s blog, which ranked the most competitive real estate markets in 2019. Out of 20 listings, three were neighborhoods in Arlington: East Arlington at #3, the Brattle Street Area at #5, and Arlington Center at #12. This is only one data point, but Redfin is a national realtor and works in markets all across the country. Arlington is a desirable place to live.

Housing costs have steadily increased over the last 20 years, modulo a brief reset during the economic recession of 2008. For example, the prior owner of my house purchased it for $151,000 is 1999. I purchased it for $359,000 in 2007 (when it was assessed at $287k). Today, it’s assessed at $501k, which is consistent with similar home sales from 2018.

The net effect: each year a new family moves to town, they have to have a more money (or be willing to spend more on housing) than a family who moved in the year before. With that in mind, I’d like to cite a few figures from the 2019 Town Survey:

  • Question 37: Indicate the number of years lived in Arlington. 59% of respondents indicated 15 years or less. Nearly 30% indicated five years or less. Despite the prices, people still move here.
  • Question 40: What was your annual household income in 2018. The most common response was “more than $200,000”, with over 28% answering that way. Nearly 71% of respondents indicated earning $100,000/year or more. Arlington’s median income is likely higher than HUD’s AMI for the Metro Boston area.
  • Question 41: What is the highest level of educated completed by a member of your household. Over 73% indicated having a masters degree or higher.

I don’t mean to knock people who’ve lived here 15 or fewer years, have advanced degrees, or have household earnings of $200,000 or more per year. I check every single one of those boxes myself. But I do want to point out that we are a highly educated and affluent community. Put another way, we have a population that matches the cost of our housing.

Twenty years of gentrification haven’t killed us: we’ve expanded town staff and services, we’re renovating public buildings, and we’re getting a new high school. Those are all good things, made possible because residents have the money to pay for them, and have been willing to do so.

We can absolutely keep the status quo we’ve had, but I want to recognize that the combination of the housing market and Arlington’s policies have created an economic barrier to living here. I see two issues: one is affordability, and the other is an imbalance between supply and demand.

There are a variety of things we could do, and I think we should consider all of them. I don’t see a viable way to relieve housing pressure that doesn’t involve more housing. And that’s what I hope we can do over the coming years: find ways to build more housing.

Does Building More Housing Reduce the Market Price?

Report by Vicki Been, Ingrid Gould Ellen, and Katherine O’Regan, Supply Skepticism: Housing Supply and Affordability, NYU Furman Center 8/20/18

Some affordable housing advocates question the premise that increasing the supply of market-rate housing will result in more affordable housing. This paper addresses the key arguments these “supply skeptics” make. Considering both theory and empirical evidence, the authors conclude that adding new market-rate homes moderates price increases does make housing more affordable to low- and moderate-income families.

At the outset, the authors review the relevant studies and conclude that “the preponderance of the evidence shows that restricting supply increases housing prices and that adding supply would help to make housing more affordable.” They then turn to several arguments the supply skeptics make. One key issue is whether adding housing in a part of the housing market will affect prices in another. The housing market is not uniform but composed of various submarkets. These submarkets relate to each other in complex ways. Critically, however, if demand forces up prices in a higher-end submarket, some buyers will turn to the next segment down and bid up prices there, generating a cascade. Adding supply at higher levels reduces this cascade and relieves price pressure all the way down. Empirical research indicates that this “filtering” process happens surprisingly quickly.


Supply skeptics may also fear that construction of new housing will exacerbate affordability problems by raising neighborhood rents or prices, fueling gentrification, and potentially displacing existing residents. New construction can have both positive and negative effects on prices or rents of nearby homes. New housing may an amenity that makes a neighborhood more attractive – and expensive. But it also absorbs demand and may reduce the incentive to upgrade existing housing to please high-end buyers. The evidence on the net effect of these effects is unclear. An important California study indicates that the production of market rate housing was associated with a lower probability that low-income residents in the neighborhood would experience displacement. But more research is needed.
The authors point to additional disadvantages of limiting supply, including pushing lower-wage workers to live in distant suburbs, where long commutes add to regional traffic woes and greenhouse gas emissions. They stress, however, that increased supply, while essential, is not sufficient to address the affordability challenge. Government intervention through subsidies and other measures is critical to ensure that housing supply is added at prices affordable to a range of incomes, and especially the lowest ones.

Four Big Housing Challenges In Metro Boston

Data in a Mass Housing Partnership report shows how far behind the Boston metropolitan area has fallen in meeting the housing needs of its citizens. There are four primary categories for measuring the inadequacies: 1. Availability, 2. Affordability, 3. L0cation and Mobility and 4. Equitability. See the full report for more data and examples. Two slides are shown below.

Despite increasing population and job growth, Mass. has one of the lowest rates of housing production in the USA
Average zoning jurisdictions in Mass. arrepresent only 10,000 people. This makes it hard to achieve meaningful, broad public policy goals.