Easier ADU rules are a growing solution

Suffolk County is at a major crossroads. Homeowners are facing renewed housing and foreclosure pressure, with too many working families, young people, seniors and longtime residents finding it harder to remain in the communities they call home. Local officials have an important opportunity to support responsible homeowners, help seniors age in place, preserve neighborhood stability and give families practical options for financial security. Accessory dwelling units are one thoughtful solution.

These units, known as ADUs, allow homeowners to create an independent living space on their property for another household. When done safely and legally, ADUs create new housing opportunities while giving homeowners additional monthly income to help cover taxes, mortgage payments and more expenses. ADUs can also increase nearby property values, the Federal Housing Finance Agency found in 2025.

For seniors especially, ADUs can help fixed-income homeowners remain in their homes, provide space for caregivers or family members, and support multigenerational living while preserving independence.

Across Suffolk, however, current ADU rules may unintentionally make legal compliance difficult for homeowners who want to create safe, permitted housing. Parking requirements, complex applications, restrictions on unit size and location, and other limitations can discourage homeowners from pursuing a legal ADU. In some cases, overly difficult rules may even push owners toward unpermitted units that do not meet fire and safety codes.

Recognizing this reality, several Suffolk town boards have made practical updates this year. In March, Riverhead lowered off-street parking requirements, allowed larger ADUs and streamlined the application process. In April, Southold lifted a restriction that prevented new detached structures like garages and cottages from containing an ADU. East Hampton followed with action of its own in May.

Now, as the Town of Islip revises its Comprehensive Plan, it has an opportunity to consider a similarly balanced approach: one that strengthens affordability while protecting neighborhood character, encouraging safe and code-compliant housing, and supporting responsible homeowners.

Under Islip's current rules, homeowners seeking an ADU must provide four off-street parking spaces, even for a unit with just one additional resident. This requirement can be a significant barrier for many.

Islip homeowners must also live in the primary dwelling as a condition of ADU approval, rather than being allowed to reside in either the primary dwelling or the ADU. This can make it harder to maintain an ADU when unforeseen circumstances make living in the primary home impractical.

Islip also does not currently allow safe, code-compliant detached structures like garages and cottages to contain ADUs, caps ADU size at 800 square feet, and requires public hearings for every ADU application, including some renewals. These rules can add cost, delay and uncertainty for homeowners trying to follow the law.

As Islip revises its plan, it can follow recent regional examples by recommending careful, homeowner-focused updates. These could include lowering the parking requirement, allowing owner occupancy in either dwelling, and simplifying approvals while maintaining safety standards.

By doing so, Islip officials can empower responsible homeowners, encourage legal housing and preserve flexibility for families facing real financial pressures. Thoughtful ADU modernization can help Islip meet its affordability goals while preserving neighborhood character, protecting public safety — and supporting the property owners who have invested in the town's future.

This guest essay reflects the views of Zak Zethner, an accessory dwelling unit policy analyst at Housing Help Inc., and Pilar Moya-Mancera, the not-for-profit organization's executive director.