Pilot houses & roof access in Philadelphia

What counts as a pilot house

The Zoning Code calls it a “roof deck access structure.” Philly Home Collective describes a pilot house as “a small enclosure that houses the stair from the floor below up to the roof deck,” which improves safety and weather protection compared with a hatch.

The zoning limits

• Access only. It “may only serve to enclose the access stairs, elevators, or other means of access.” No bonus room, bar or storage.
• Size. Max 125 sq ft, plus 40 sq ft if it contains an elevator. This cap doesn’t apply in RM-2, RM-3, RM-4, RMX-3, CMX-3, CMX-4, CMX-5 and IRMX districts.
• Height. Max 10 ft above the deck surface, in every district.
• Setbacks. The same front setback as the deck, plus another 5 ft for any part more than 42 in above the deck. It must also sit 5 ft back from the rear building line.

Meeting these limits makes the structure a permitted appurtenance that isn’t counted against the district’s height limit. Anything larger is a zoning question, and may mean a variance. Other rooftop structures, such as canopies and pergolas, must meet the base district’s height, area and setback rules unless the Code gives them a specific exception, per an L&I FAQ.

Hatch or pilot house?

A roof hatch or ship’s ladder costs less and is simpler to permit, but it’s harder to carry things up and easier to leak. A pilot house costs more, adds weight, and, in historic districts, is the part most likely to be visible from the street. Ask your builder to price both.

What it costs

Philly Home Collective lists pilot houses at $4,000–$30,000+ in its Fishtown cost breakdown. The range is wide because a pilot house can be anything from a simple framed box to a glass-and-steel enclosure. Full cost guide.