Permit Required? Required
Typical Fee Range $1,500–$5,000 Governed by local zoning; building permits range from $500–$2,000 plus trade permits.
Fee Method Valuation-based
Apply Online Apply at Philadelphia Department of Licenses and Inspections →

What's Required in Philadelphia

  • Permit required for all Accessory Dwelling Units (ADUs), detached or attached
  • Property must be owner-occupied (either the main house or the ADU)
  • Separate zoning approval is typically required as a prerequisite
  • Must meet PA energy efficiency requirements and IRC ceiling heights (min 7 ft)
  • Smoke and CO detectors mandatory in every sleeping room and hallway
  • At least one egress window per bedroom is required

How to Get a ADU Permit in Philadelphia

1

Step 1: Zoning Variance/Approval

Check Philadelphia zoning for ADU eligibility; historic properties have specific bonus paths.

2

Step 2: Full IRC Plans

Prepare detailed architectural, structural, and energy (Title 24) plans.

3

Step 3: eCLIPSE Submission

Apply for the 'New Construction' or 'Major Alteration' permit via eCLIPSE.

4

Step 4: Fee Payment

Pay building fees ($500+) plus trade permit fees for electrical and plumbing.

5

Step 5: Inspection Sequence

Schedule Slab, Framing, MEP Rough-in, and Final Inspections.

Frequently Asked Questions

Yes, but it depends on your specific zoning district and lot size; historic properties have more flexibility.
Total permit costs (building + trades) typically range from $1,500 to $5,000.
Zoning rules vary, but many ADUs are limited by lot coverage and height rather than a specific square footage.