The ABCs of Affordable Housing in Arlington

Arlington has had a shortage of affordable homes for some time, and now the problem is even more pressing given Amazon’s decision to move one of its new headquarters to the county. So what are local officials going to do, and what are they already doing about affordable housing?

To help have that conversation, let’s define some terms that are distinctly Arlington in the region’s housing parlance. With the regional and national focus turning more squarely onto Arlington County, here’s a brief guide.

AHMP it up

Let’s start with a relative newcomer to the scene, the 2015 Affordable Housing Master Plan (AHMP). The AHMP is part of the county’s comprehensive plan, and guides affordable housing policies and strategy.

It has some important and fairly aggressive goals and objectives, such as one that aims to have 17.7% of the county’s housing stock affordable to low-income renter households by the year 2040. According to the latest annual report, this number currently stands at only 8.8%, so we have a long way to go.

Is that housing an AD or ADU? Or is it a CAF?

Many jurisdictions in the region have been slowly modifying their land use and zoning laws to allow for accessory dwelling units, or accessory apartments. These are additional dwelling units located inside or connected to a single-family home.

These are great because they help both the homeowner, who receives rental income for the unit, and the renter, who is able to rent an apartment for a reasonable rate in places where not much rental housing is available. External (detached) ADs are not yet allowed in Arlington, but we are hoping to see a new proposal for these come to the County Board in 2019.

In DC and Maryland, many refer to these types of homes as ADUs, but not so in Arlington, which calls them ADs (Accessory Dwellings). Why is that? The term ADU in Arlington is reserved for Affordable Dwelling Unit. Specifically, an ADU is a dwelling unit affordable to low-income households that results from application of the county’s Affordable Housing Ordinance (we’ll get to that in a second).


There is another important Arlington-specific acronym you need to know when it comes to affordable housing: CAFs. Committed Affordable Units (CAFs) are rental units that are guaranteed to remain affordable to low and/or moderate-income households for a specified period of time, usually 30 years or more. This is done through a variety of funding methods, including the Affordable Housing Investment Fund (AHIF) described below, and through the Affordable Housing Ordinance.

CAFs and ADUs are classified by Area Median Income (AMI), a national measure you can read more about here. For example, most, but not all, CAFs in Arlington are affordable to households earning 60% of AMI, which is about $49,000 for an individual or $70,000 for a family of four. The US Department of Housing and Urban Development (HUD) annually publishes median incomes by household size, the AMI is used to define a person’s eligibility for housing programs.

Finally, there’s one more aronym on this topic you should know about: MARKs. Market Affordable Units (MARKS) are apartments in the private market with relatively low rents but the owners have made no commitment to retain as affordable in the future. In some places these are referred to as Naturally Occurring Affordable Housing (NOAH). These still exist in Arlington, but have dwindled dramatically over the past few decades.

Back in the year 2000, the County had almost 20,000 MARKs affordable to people at 60% of AMI, but in 2018 there are just over 3,000 remaining due to rent increases and redevelopment. A new initiative called the Housing Conservation District (HCD) is working on creating incentives to keep these remaining units affordable.

Where’s the money come from? AHIF, CDBG, HOME, LIHTC, and MIPAP, of course.

It’s expensive to keep homes affordable over time, especially in a market like our region where we have an overall housing shortage. There are some federal resources available to help, and Arlington also has its own local sources of funding.

For most rental housing properties, including affordable ones, the bulk of funding to support the development comes from a bank loan that is paid back from the rents paid by residents. The higher the rents, the greater share of the development costs paid for by this kind of loan. So affordable properties with lower rents need other funding sources to fill the gap between the amount of loan supported by rents and the total cost of the project.

The most common form of funding to fill this gap for affordable rental housing is Low Income Housing Tax Credits (LIHTCs), which you can read in more detail about here. These tax credits, which are allocated to affordable housing projects by the IRS through state housing finance agencies, may be sold to private investors to raise funds for affordable housing projects. In Virginia, the LIHTC-allocating agency is the Virginia Housing Development Authority (VHDA), which also provides loans for affordable rental housing and first-time homebuyers.


Other federal programs include the HOME program and Community Development Block Grants (CDBGs). This are two federal programs that provide funds to cities and counties for a variety of housing, neighborhood improvement, and economic development activities that will benefit low- and moderate-income residents.

Locally, Arlington maintains the Affordable Housing Investment Fund (AHIF). This is a county program that provides low-interest loans to developers to build or renovate housing affordable to low- and moderate-income households. Over the past five years, Arlington has allocated between $25 million and $37 million in AHIF funding per year from a variety of sources.

Sources of funding for AHIF come mainly from annual general fund contributions (which in FY19 is $14.3 million) as well as developer payments resulting from the Affordable Housing Ordinance ($10.3 million in 2018) and loan repayments from prior AHIF borrowers. For comparison purposes, DC commits to funding $100 million annually into its housing trust fund.

Arlington also has a few programs that directly help people renting or buying homes. For example, the Housing Grants Program is a county-funded rental assistance program serving low-income working families, elderly persons, and people with disabilities. Rent subsidies typically reduce participants’ share of the rent to no more than 40% of their income.

This program is similar to the federal Housing Choice Voucher program, also known as Section 8 housing assistance, which is also available to low-income renters in Arlington. In 2018 there were 1,234 households with Housing Grants and 1,504 with Housing Choice Vouchers, so Arlington’s local program serves almost as many as the federal program does.

For homebuyers, there is the Moderate Income Purchase Assistance Program (MIPAP). This provides down payment and closing costs loans to first-time home buyers with incomes below 80% AMI. Unfortunately this program has been very small, helping only four first-time home buyers in 2018.

What can be built where? Check the GLUP and FBC.

Arlington’s zoning code focuses much of its growth along transit corridors by allowing high density buildings there, but maintaining other neighborhoods at much lower densities.

The amount and type of development is dictated by Arlington’s General Land Use Plan, or GLUP, the primary policy document guiding the character of future development in Arlington. The GLUP was first developed in 1961 and was amended in the 1970s to include plans for high-density development in the Rosslyn-Ballston and Jefferson Davis Metro corridors.

Since then it has been updated on a regular basis as areas throughout the county go through comprehensive planning updates or special update requests are made. The next big update is expected to come along the Lee Highway corridor, which is beginning a major three-year planning initiative in 2019.

Photo by Jeremy Galliani | Unsplash

Photo by Jeremy Galliani | Unsplash

Arlington’s Affordable Housing Ordinance, which is part of the county’s zoning ordinance, helps create new affordable units either directly or indirectly through the AHIF, described above. In essence, developers can apply for increased density within the site plan approval processes, but they are required to provide a certain number of units as ADUs, or alternatively to pay into the AHIF (you follow now, right?). Projects that are consistent with the GLUP must follow the standard ordinance, but those applying for density beyond what is anticipated in the GLUP are subject to additional affordable housing requirements.

Finally, along Columbia Pike in Arlington we have a Form-Based Code (FBC). This is an alternative form of zoning that developers can opt into rather than following the current by-right zoning for their property. The code is separated into two parts – one for the “Commercial Centers” and one for the “Neighborhoods.” The Neighborhoods FBC has significant affordability requirements, but none are included in the Commercial Centers FBC on the Pike.

While not an exhaustive list of all the terms involved in discussions about Arlington’s housing policies, this should at least give a place to start.

This post by Michelle Winters, AHS Executive Director, was originally published on Greater Greater Washington’s blog on January 3, 2019.