Supporting Upgraded Property Projects and Lending for Yards (SUPPLY) Act

The SUPPLY Act establishes a federal program to insure second loans (additional financing) for building accessory dwelling units (ADUs) on single-family properties. This insurance, administered by the Department of Housing and Urban Development, covers up to 30% of a standard one-unit home loan amount or 100% of the property value after construction (with potential increases based on 50% of projected rental income). Homeowners seeking to add ADUs - such as backyard cottages, converted basements, or detached units - can use this insurance to secure financing, with a government premium of up to 1% annually. The bill also requires Fannie Mae and Freddie Mac to purchase and securitize these insured loans, potentially expanding access to ADU financing.