Internal units: These are built entirely within the existing home's footprint. More often than not, that's a basement renovation that can take advantage of an existing doorway that may or may not be inside a bulkhead. In a case like this, you would remove the bulkhead cover and create a set of code-compliant stairs and a landing. The landing should have some type of drain and a drywell below to handle rainwater.
Several housing organizations, like the National Association of Home Builders and Mortgage Bankers Association, have expressed support for the legislation, arguing that it will open doors for homeowners and would-be homeowners to build generational wealth and equity. The move would also address the nation's housing supply crisis. Still, industry leaders caution that federal backing alone won't solve all the obstacles. Challenges around valuation, underwriting and builder capacity remain barriers to scaling ADUs into a widespread affordability solution.
