CPHD
Lot Coverage
County Board Approves Changes to Lot Coverage
The County Board approved changes to the Lot Coverage provision of the Zoning Ordinance on Tuesday November 15 th . Here are the key provisions and what you need to know:
- The changes do not affect existing houses. All existing houses are grandfathered by the County Board 's approval so that if you exceed the new coverage provisions it is now a legal nonconforming structure. This means that while you cannot add on to your house unless you comply with the new requirements, you are legal and you can rebuild it if damaged by natural causes.
- If you want to redevelop or add an addition you are now subject to the new requirements.
- The coverage provisions are based on a sliding scale determined by the zoning district of your lot and are applicable to both new construction and additions. Click here to see the adopted coverage provision and table.
- The changes include an incentive for front porches and garages in the rear yard.
- The changes are effective on November 16, 2005. If you filed a permit prior to that date you are under the old rules.
- Included in the changes are changes to the existing nonconforming provisions that allow:
- Nonconforming houses to be rebuilt as they existed if they are damaged by a natural disaster.
- Nonconforming houses can be added to if the additions comply with all zoning requirements.
- Removes the provision that houses that are nonconforming due to lot size or height are limited to expansion by 50% of the floor area of the house.
- A revised “How to Calculate Lot Coverage” disussion and relabel data to help calculate lot coverage has been placed on the web site to assist you in calculating the coverage on your lot.
- Due to the changes, staff will not be able to review and approve building permits on a “a “walk thru” basis so permit requests will have to be left with zoning while they are reviewed.
What is lot coverage:
Lot coverage is simply the ratio of the occupied area (buildings and driveways) to the total area of a lot. For example on a “R-6” zoned lot, if the occupied area is 2,400 sq.ft. and the total lot area is 6,000 sq. ft., coverage would then be equal to 40%. In Arlington, maximum allowable lot coverage is 56%.
To learn more about lot coverage and how it affects lots in different zoning categories please review the attached document “Lot Coverage Study”. (PDF Format)
County Estimates of Lot coverage
About The Estimates/Data Disclaimer
Data concerning lot coverage from Arlington County Planning Staff is provided as a tool to help property owners gauge the impact of lot coverage zoning parameters on properties in the County. This data set has also been used at a macro level to understand the implications of policy changes and magnitude of affected properties.
This data is from two sources. Building footprint area, accessory building area and driveway area data is taken from a study conducted by Arlington County Mapping Center staff in March of 2003. This study calculated area from Geographic Information System (GIS) files that were derived from 2001 aerial images of the county. Although aerial images may over exaggerate building size somewhat (roof eaves and overhangs are included in footprint figures), it is the best footprint data available to staff at this time. More recent and or improved data will be provided as soon as it becomes available.
Lot size and detached garage information is derived from the Arlington County Department of Real Estate Assessments database. This data is updated daily and is therefore not a static data source. This information was downloaded from Real Estate files in March and April of 2005 and is therefore accurate for that period only.
Because the number of properties in the County is constantly changing, and new additions, development or redevelopment is likely to have taken place since 2001, this data set is intended to be used only as a guide for understanding lot coverage and is for reference purposes only.
Neither GIS or Real Estate data should be substituted for a property survey or official plat information used in land sales. Please contact Justin Clarke with questions about the data.
Finally, please be aware that the calculation of unused coverage does not take into account setbacks or other constraints that may prevent development of unused square footage.
Instructions to view Interactive lot coverage data (PDF Format)
