Sussex County, DE Zoning Overlays & Bonuses: Density Bonus Law (2026)

Chapter 72 of the Sussex County Code creates the MPHU density incentive for any applicant proposing at least 35 dwelling units (or seeking building permits for 35 or more units where no subdivision review applies) on qualifying land. Under § 72-7A, a project that sets aside 15% of its units as MPHUs earns a density bonus keyed to the income tier served: 20% for Tier A units (100%-125% of area median income), 25% for Tier B (80%-100% AMI) and 30% for Tier C (80% AMI or below).

Projects mixing tiers receive a weighted-average bonus; the code's own example shows a project with 1/3 each of Tier A, B and C earning a 25% weighted incentive. In planned development and mixed-use zones with flexible standards, the MPHU set-aside is a flat 15% of total units regardless of tier. To use the incentive, the applicant must execute an MPHU agreement negotiated with the Department of Community Development and Housing and the County Attorney under § 72-8, specifying the number and price level of MPHUs, the construction and delivery schedule, and acknowledgment that development-cost risk falls on the applicant.

Participating projects also receive expedited plan review, but § 72-7B(2) caps total density, bonus units included, at 12 dwelling units per acre. The County Council retains authority under § 72-7C to modify zoning standards such as minimum lot size, setbacks, building height and parking to fit an approved MPHU project's design. Resold or new MPHUs stay under resale-price and owner-occupancy controls for a 20-year control period measured from the date of sale.