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Zoning, planning & development

Get a sky plane review

Service overview

Building projects located on CMX-4 and CMX-5 lots have bulk and mass requirements. These rules safeguard the balance between open space and development in Center City.

Sky plane controls are one option for complying with the requirements. By limiting how much visible sky a building can block, this method protects light and viewsheds within dense street corridors. The sky plane requirements vary by street.

You can show your project’s compliance by undergoing a sky plane review. Alternatively, you can demonstrate compliance with bulk and height requirements by using open area controls, which limit the lot coverage of a building at various height intervals.

When you apply for a zoning permit, the Department of Licenses and Inspections (L&I) will identify projects that may choose to use sky plane controls. Please note that sky plane is just one method to assemble bulk and mass of a tall building.


Applicants include:

  • Developers.
  • Architects.
  • Engineers.
  • Expediters.

Where and when

The PCPC office is located at:

1515 Arch St.
13th Floor
Philadelphia, PA 19102

Office hours are Monday through Friday, from 8:30 a.m. to 4 p.m. Appointments are required.


When you apply for a zoning permit, the cost of a sky plane review is included in its fee.


Reviews can be conducted electronically through eCLIPSE or as an over-the-counter consultation with PCPC staff.

To schedule an in-person plan review, use our online appointment system. Once you’ve entered your contact information, select “Planning Commission” and choose “Urban design plan review.”

PCPC staff may require a meeting for large or complex proposals. You must bring the following materials to your review or submit them in eCLIPSE:

  • A zoning plan. This plan should include a table that shows compliance with blockage percentages at the regulated building height intervals.
  • Plotting sky plane diagrams for all relevant streets.
  • Your zoning permit application.

Refer to the PCPC regulations for complete submission requirements.

After PCPC staff issues an approval, the Department of Licenses and Inspections (L&I) will continue with the permitting process.