Herndon Planning Commission reviews changes to accessory dwelling unit rules

The Town of Herndon is looking to update decades-old rules involving accessory dwelling units to make the process less burdensome for homeowners.

The Herndon Planning Commission held a virtual public hearing on Monday (July 26) on a proposed ordinance that the town council will ultimately vote on whether to approve.

“Our current regulations are 38 years old,” the town’s zoning administrator, David Stromberg, said, adding that the age of the existing ordinance is not problematic in and of itself, but the town has changed over the decades.

In the works since April, the decision to revisit the rules for ADUs — smaller dwellings that exist on the same property as a primary residence — was prompted by frustrations expressed by some residents who recently underwent the permitting process, according to Stromberg.

Neighboring governments have already loosened restrictions. Fairfax County revised its rules for accessory units, which it calls accessory living units, as part of a larger zoning overhaul this summer, dropping a requirement that the units be restricted to older adults and people with disabilities.

Herndon also plans to remove those restrictions.

The town’s planning commission is considering making the process less restrictive in other ways, too, such as by allowing many types of ADU additions to occur by right as opposed to requiring an approval process. That could also include allowing second kitchens under certain circumstances.

The town has also noted that smaller homes may be confined by the existing code, so officials are considering possible changes to square footage requirements.

Currently, attached, internal, and detached units can be up to 1,200 square feet or 35% of the gross floor area of a principal dwelling unit, whichever is less. So, if a home is 1,000 square feet, you are currently limited to a 350 square-foot addition, Stromberg noted.

That could change to 1,200 square feet or 40% of a principal dwelling unit for attached and internal dwelling units and be a one-size limit of 800 square feet for detached dwelling units.

Among a variety of issues, the commission has also been looking at limiting the number of wet bars as well as possibly dropping an extra parking space requirement for an ADU if it’s within 0.25 or 0.5 miles of the Herndon Metro station.

Officials have time to continue their review: The second phase of Metro’s Silver Line project has faced delays with no confident expectations any longer for when the new stations will actually open.

Only one member from the public commented during the hearing: resident Gordon Dean, who said that he’s a strong proponent of accessory dwelling units and hopes future ones could help with Section 8 housing.

The planning commission is continuing the matter to its Aug. 23 meeting, which it plans to hold in person.