Expanded Housing Option (EHO) Development

Expanded Housing Option (EHO) Development offers an alternative on single-family residential lots that allows for the construction of duplexes, townhouses, and multifamily buildings that meet the design standards in Arlington County Zoning Ordinance (ACZO) §10.4 Expanded Housing Option Development(PDF, 239KB).   

EHO projects must obtain zoning approval before any building or trades permits can be issued. This zoning approval is granted through an Expanded Housing Option Permit, or EHO Permit. 

EHO Permits DO NOT authorize construction or occupancy.  An issued EHO Permit does not constitute approval for any required building permits, trades permits, or certificates of occupancy. 

No more than 58 EHO Permits can be issued in per calendar year, with the following allocation:

R-5: 7 permits
R-6: 30 permits
R-8, R-10 & R-20: 21 permits (total)

Submission Requirements

An application for an EHO Permit must be submitted to the Zoning Division through the Permit Arlington online portal. Before applying for an EHO Permit, applicants can request a Code Consultation to determine whether their proposed EHO project is eligible and meets the minimum eligibility requirements of the Zoning Ordinance.Contact the Zoning Division by email or phone to schedule a pre-submission meeting.   

The pre-submission meetings will also provide an overview of the associated requirements of the Virginia Uniform Statewide Building Code (VUSBC) that are overseen by the Inspection Services Division (ISD), as well as environmental considerations and best practices overseen by the Department of Environmental Services (DES), and the Department of Parks & Recreation (DPR).

Eligibility Criteria

Eligibility Criteria 

Expanded Housing Option Developments are permitted by-right on lots meeting the following criteria: 

  • The lot is located in the R-5, R-6, R-8, R-10, or R-20 zoning districts
  • The lot cannot be located within a designated planning district in the GLUP
  • The lot is less than 43,560 sq. ft. (1 acre) in land area 

There are also minimum lot size requirements for by-right Expanded Housing Option projects: 







Minimum Lot Area

20,000 sq. ft.

10,000 sq. ft.

8,000 sq. ft.

6,000sq. ft.

5,000 sq. ft.
6,000 sq. ft.*

Minimum Lot Width

100 ft.

80 ft.

70 ft.

60 ft.

50 ft.

* R-5 lots must have 6,000 sq. ft. or more for buildings with 5-6 units 

Lots not meeting these minimum dimensional standards can be developed with EHO project if the lot is nonconforming, per ACZO §16.1.1 Nonconforming Lots. EHO development on nonconforming lots is limited to no more than four (4) dwelling units unless the lot is 7,000 sq. ft. or more.

EHO developments on lots larger than 1 acre require County Board approval of a special exception use permit

Housing Types

Housing Types

Expanded Housing Option Development allows for the construction of several residential dwelling forms including: 

  • Duplexes 
  • Semidetached Dwellings 
  • Townhouses with up to 3 units 
  • Multiple-Family buildings with up to 6 units 

Expanded Housing Option Development also allows for alterations and/or additions to convert existing one-family and two-family dwelling into Expanded Housing Option dwellings, per ACZO §16.2 Nonconforming Buildings and Structures

Development Standards

Development Standards

Expanded Housing Option dwellings share many development standards in common with One-Family Dwellings but there are several additional standards that are unique to Expanded Housing Option developments. 

The standards in common with One-Family Dwelling, found in ACZO Article 3, include: 

  • All definition, measurement and calculation standards such as lot coverage [ACZO §3.1.4.A], main building footprint [ACZO §3.1.4.C], building height [ACZO §3.1.6.A], and gross floor area [ACZO §3.1.1.C]
  • Main building bulk and placement requirements such as street setbacks [ACZO §3.2.6.A.1] and lot line setbacks [ACZO §3.2.6.A.2] 
  • Allowed setback and yard encroachments for porches, stairs, decks and patios [ACZO §3.2.6.A.3] and detached accessory buildings [ACZO §3.2.6.A.2(c)] 

Standards unique to Expanded Housing Option Development dwellings, found in ACZO §10.4(PDF, 239KB) include: 

  • Lot Coverage
  • Main Building Gross Floor Area (GFA)
  • Parking Requirements
  • Main Building Design Standards
  • Landscaping and Screening

Lot Coverage

Lot Coverage and Main Building Footprint

Similar to single-family dwellings, Expanded Housing Option development is subject to the following lot and main building footprint coverage limits: 






Maximum Lot Coverage






Maximum Lot coverage with porch*






Maximum Main Building Footprint Coverage






Maximum Main Building Footprint Coverage with porch*






Maximum Main Building Footprint Cap

2,380 sq. ft.

2,520 sq. ft.

2,800 sq. ft.

3,500 sq. ft.

4,480 sq. ft.

Maximum Main Building Footprint Cap with porch*

2,590 sq. ft.

2,772 sq. ft.

3,136 sq. ft.

3,920 sq. ft.

5,320 sq. ft.

* To qualify for a porch bonus, there must be at least one street-facing porch of 60 sq. ft. or more. 


Gross Floor Area

Main Building Gross Floor Area (GFA)

Expanded Housing Option developments are subject to limits on the total floor area of the main building as follows: 


4,800 sq. ft.


5,000 sq. ft.


7,500 sq. ft.

Multifamily, 3-unit

6,000 sq. ft.

Multifamily, 4-unit

7,200 sq. ft.

Multifamily, 5- or 6-unit  

8,000 sq. ft.


As defined in the Zoning Ordinance, Gross Floor Area is the "sum of the area of the horizontal surface of the several floors of a building measured from the exterior faces of exterior walls, to include all floor area not defined as gross parking area." [ACZO §3.1.1.C] 

In calculations, the area of all floors measured from the abutting exterior walls are counted toward the main building Gross Floor Area. The only instances where floor area is NOT included in Gross Floor Area calculations are when: (1) located in a garage; or (2) located under a gabled, hipped, gambrel, or mansard roof and NOT BETWEEN two or more exterior wall plates. Learn more.(PDF, 140KB) Gross Floor Area is calculated for the entire main building, across all dwelling units. 



Parking Requirements

Expanded Housing Option developments are required to provide one (1) off-street parking space per dwelling unit [ACZO §10.4.6.A Parking].

This can be reduced to half (0.5) a space per unit when an Expanded Housing Option project is transit proximate, which is defined as a lot located 0.75 miles from the entrance of a Metrorail Station or a half mile from a Premium Transit Network transit stop. Required parking can also be reduced to half a space per unit if a parking survey by the Department of Environmental Services (DES) shows that the Expanded Housing Option project is located on a block where on-street parking is less than 65% occupied. Lots on cul-de-sacs are NOT eligible for reduced parking, and must provide one (1) parking space per unit. 

There are restrictions on the location of surface parking spaces for Expanded Housing Option development [ACZO §10.4.6.B Location of Parking].

Lots in the R-5, R-6, or R-8 zoning districts can locate no more than two (2) parking spaces in a yard fronting a street right-of-way; and lots in the R-10 or R-20 zoning districts can locate no more than three (3) parking spaces in a yard fronting street right-of-way. Corner lots in any zoning district are allowed a total of four (4) surface parking spaces in yards fronting street rights-of-way. Lots abutting an alley improved to County standards CANNOT locate surface parking spaces in any yard fronting on a street right-of-way. 

Additional parking restrictions for Expanded Housing Option developments include: 

  • Curb cuts cannot exceed 17 ft. in width; 
  • Any parking spaces located within the footprint of the main building, i.e. under a cantilevered carport, must be enclosed;  
  • All garage entrances facing a street right-of-way cannot exceed 50% of the main building façade facing that street right-of-way; and 
  • Tandem surface parking spaces are only counted as one (1) required parking space. 

Design Standards

Main Building Design Standards

Expanded Housing Option developments are required to have at least one (1) main building entrance facing a street right-of-way AND no more than one (1) building entrance facing a side or rear lot line.

For semidetached homes and townhouses, the entrance to every dwelling unit must face a street right-of-way. In addition, any exterior stairs accessing the entrance to a dwelling unit above ground-level must be enclosed, unless the stairs face a rear yard.

Landscaping and Screening

Landscaping and Screening

All Expanded Housing Option development is required to provide and/or maintain shade trees.

  • Four (4) trees are required for projects with four (4) or less units.
  • Eight (8) trees are required for projects with five (5) or six (6) units.

In addition, HVAC units, mechanical equipment, exterior storage, and trash collection areas cannot be visible from any street right-of-way and must be screened by fencing, walls, landscaping, or other structures.

Application Requirements

EHO Permit applications must be submitted in Permit Arlington. Click "Create" and select "Zoning Application."

All applications must include the following supplemental materials: 

  • Floor plans 
  • Building elevations 
  • Existing property plat and building location survey 
  • Proposed property plat and building location survey 
  • Landscaping and/or tree preservation plans 

All plans, elevations, surveys, and plats must be scaled. Plats and surveys should be certified. Applicants are encourage to work with a professional architect, designer or surveyor to create suitable supplemental materials. Additional supplemental materials may be requested during review. Allow approximately thirty (30) days to process an EHO Permit after the application is accepted as complete by the Zoning Division.  

NOTE: Applicants may apply for a Building Permit at the same time that they apply for an EHO Permit to the Zoning Division. However, the Building Permit cannot be issued until after the EHO Permit is issued. Once a Building Permit is issued, construction can proceed. Be aware that some residential properties are considered commercial per the Building Code and require commercial permits. Applicants should determine whether their project is Residential or Commercial before applying for a Building Permit.

Upon its completion, applicants must file for a Certificate of Occupancy (CO) with the Zoning Division.


Fee schedules provide the range of fees charged for each type of application or activity related to land development in Arlington. Fees cover permitting, plan review, enforcement, inspection, service delivery, performance agreements, and conditions. There are separate fee schedules for the Inspection Services Division (ISD), Zoning, and the Department of Environmental Services (DES). Some permits involve fees from more than one schedule.