Accessory dwelling unit contractor

Looking for accessory dwelling unit contractor in Philadelphia, PA? Call AccessoryDwellingUnit Pros for a contact a provider — no obligation. Licensed adu builders serve Philadelphia and the surrounding area, and you'll get straight answers on timing and what affects the price.

Last updated: September 24, 2026

What affects the price

Building an ADU is a custom project, so costs vary based on your specific choices. Site conditions are the biggest factor; if your land requires significant grading, utility extensions, or foundation work, those expenses add up quickly. Choosing high-end finishes, custom cabinetry, or complex roof lines will also push the budget higher compared to a standard design. Prefabricated units often offer predictable costs, while custom site-built structures allow for more flexibility but can be harder to estimate upfront. Exact pricing confirmed free on the call.

About this service

A contractor manages the trades, materials, and timeline required to complete your backyard home. You need a contractor when you have design plans ready or need a lead to coordinate electricians, plumbers, and carpenters to get the structure move-in ready. They act as your project manager, ensuring that the work is finished on schedule and adheres to the building plans filed with your local municipality. Their role is essential for keeping the construction phase organized and safe.

Frequently asked in Philadelphia

What are the disadvantages of ADUs in Philly?

Potential disadvantages of ADUs in Philadelphia might involve navigating the city's historic district regulations, ensuring adequate utility services, and understanding potential impacts on property taxes. You'll also need to consider the upfront construction costs. The pros can help you assess these.

How much does an ADU cost in Pennsylvania?

What are the rules for ADUs in Philadelphia?

Philadelphia has specific zoning ordinances for ADUs, which often include regulations on lot size, setbacks, and the type of ADU permitted. These rules are designed to integrate new units harmoniously into existing neighborhoods. The pros are knowledgeable about these local requirements.

Is ADU allowed in Philadelphia?

Yes, ADUs are allowed in Philadelphia, but they must comply with the city's zoning and building codes. The specific requirements can vary based on location and the type of ADU. A call to the pros can clarify your property's eligibility and needs.

Can I add an in-law suite in Philadelphia?

Adding an in-law suite, which is a type of ADU, in Philadelphia is possible, provided it meets all city zoning and building codes, including egress and safety requirements. The pros can evaluate your home's suitability and guide you through the necessary permits and construction.

Also serving nearby: Trenton · Allentown · Reading · Elizabeth · Newark

All cities in Pennsylvania →

More on this: HUD ADU resources — ADU policy and financing research.

Service area details

1,550,542residents

11,540per sq mile

8ZIP codes served

Serving all of Philadelphia — population 1,550,542; about 11,540 residents per square mile across 134.4 sq mi. ZIP codes covered include 19019, 19092, 19093, 19099, 19101, 19102, 19103, 19104.

Neighborhoods served in Philadelphia: Old City, Rittenhouse Square, Fishtown, Germantown, South Philly — and every surrounding area.