Lancaster County, NE Accessory Structures: ADU Rules (2026)

050, adopted by Resolution No. R-18-0094 in December 2018, allows one accessory dwelling unit per lot by special permit in the AG zoning district, on a lot of 20 acres or larger, counting abutting section-line and half-section-line road right-of-way toward that minimum. The ADU's total square footage cannot exceed the lesser of 1,000 square feet or 40 percent of the principal dwelling's square footage, excluding garages, carports and mechanical equipment space, with that principal-dwelling figure locked in as of the date the special permit application is filed.

No more than two bedrooms are allowed in the unit. The lot owner must live on the property, in either the principal dwelling or the ADU, and must file a deed restriction agreement with the Register of Deeds, satisfactory to the County Attorney, barring the ADU from ever being sold separately from the principal dwelling; that filing must happen before any building permit issues for the ADU. The ADU must share the same access point to the public or private street as the principal dwelling and must meet the same setbacks as the district requires for the principal dwelling, with a height that cannot exceed either the district limit or the principal dwelling's own height, whichever is lower.

A detached ADU cannot sit more than 200 feet from the principal dwelling and cannot sit closer to the street right-of-way than the principal dwelling does. Utilities must be shared with the principal dwelling unless the owner demonstrates a practical problem tied to topography or another unique site condition.