In each Philadelphia neighborhood, you will find buildings that are seriously old, especially so in the Northwest neighborhoods like Chestnut Hill, Mt. Airy, and Germantown.

It is typical for historic houses (and even apartment buildings) in Northwest Philadelphia to have seen the turn of more than one century. So, what happens when homeowners want or need to change a detail on the interior or exterior of a historic property? What is the proper way to go about it, and why are these protections important?

In a statement to the Local, Krista Gebbia, conservation and easements manager at the Chestnut Hill Conservancy, said, “Preserving historic homes protects the character, history, and sense of place that define our communities.”

She added, “Thoughtful preservation strengthens community identity, reduces construction waste, and conserves the craftsmanship and materials that cannot be replaced. These protections are not about limiting homeowners but about ensuring that changes respect the home’s character and the neighborhood’s shared history.”

First, homeowners should be aware of their property’s historic status. Homeowners can find out if a building has local historic protections by going to the Philadelphia Register of Historic Places on phila.gov and using the property map. They also offer a PDF list of properties on the site.

Homeowners can also email the Philadelphia Historical Commission (PHC) at preservation@phila.gov with any questions regarding their property’s historic status and guidance for any proposed work on their property.

In a statement to the Local, the PHC wrote, “(If) the property is regulated by the Philadelphia Historical Commission, the staff of the Historical Commission are available as a resource. Staff are very knowledgeable about historic preservation and the permitting process. They can tell a property owner if the proposed work satisfies historic preservation standards, for example.”

Additionally, they said, “The Historical Commission will provide technical assistance to any owner of an older or historic property in Philadelphia, but the Historical Commission only regulates properties listed on the Philadelphia Register, not the National Register. However, it should be noted that there is a lot of overlap between the two registers.”

The National Register of Historic Places can be found at nps.gov.

How the process works

Historic property owners require PHC approval if the proposed alterations require a building permit or change the exterior of the building or site features.

According to the city’s website, a building permit is needed for any work that constructs a new building, enlarges or adds to an existing structure, changes the interior or exterior of an existing structure, partially or fully demolishes a structure, changes the occupancy classification of any part of a building, increases the occupant load in a space, includes major repairs that aren’t part of regular maintenance, includes 5,000 sq. ft. or more of earth disturbance.

Reaching out to the email listed above, property owners can ask PHC staff for guidance regarding any proposed work. Requests should include name, contact information, and address of the property in question. Relevant material, including photos or design plans, should be attached to the email in an Adobe or PDF format.

The PHC noted, “to receive official approval for work, a property owner must apply for a building permit from the Department of Licenses and Inspections (L&I). This will initiate the project review process. The city’s online permitting system will automatically notify the Historical Commission if a permit application pertains to a property on the Philadelphia Register of Historic Places and begin the review.”

Protections and fines

Whether knowingly or unknowingly, property owners can sometimes make changes to their property that violate historic protections. In these cases, the owners will receive a violation and fine from L&I and be given a timeline to correct it.

The PHC said their “staff reviews and approves most applications without referral to the Commission itself. Currently, the Historical Commission regulates more than 14,500 properties. It reviews and approves about 2,500 permit applications annually. It requests about 25 violations annually for work to historic properties without permits and approvals or in excess of permits and approvals.”

Recently, the Local reported on a historic property built in 1875 within the Awbury Arboretum, whose owner replaced its original wooden windows with vinyl substitutes without approval from the Philadelphia Historical Commission (PHC). The property received a violation from the city’s Department of Licenses and Inspections (L&I) for not obtaining a permit. The property owner was ordered to correct the issue by Aug. 19.

Robert Peters, who owned the Awbury Arboretum house for over a decade and maintains power of attorney over the property, told the Local, “We were unaware we needed a permit. My wife was unaware she needed a permit to do the work. … We weren’t aware that they cared about the fact that it’s vinyl instead of wood. We thought that all they cared about was the look; the look exactly matches what was here. So we didn’t think we were doing anything wrong.”

In response, the PHC wrote, “In October 2023, the property received a violation for the unpermitted construction of an outdoor deck, a process through which [Peters] was informed that alterations to the exterior of a property listed on the Philadelphia Register of Historic Places requires Historical Commission review and approval.”

Peters claims the original windows were “extremely hard to maintain,” and the vinyl windows provide superior insulation, with wood replacements being “two to three times more expensive per window.”

He added, “We didn’t go to Home Depot and buy windows, they were custom-made specifically to copy the design so the look would not change at all. … It’s superior insulation value by far. We do know it’s like maybe half, or even more, cheaper than a wood replacement window.”

However, the PHC noted, “Historic windows specifically are important character-defining features of historic buildings and play significant roles in establishing the architectural identities of those buildings. Installing non-historic windows can significantly degrade a historic building’s integrity.”

Advice from the Conservancy

This week, the Chestnut Hill Conservancy launched a “Resources and Tools” page on their website at chconservancy.org to provide a guide to owning a historic home. The website provides information on maintenance and restoration, standards and guides, and video and digital resources on their YouTube channel @chconservancy. The Conservancy will continue to update the page and provide more resources.

Gebbia said, “Every project is unique, and the Conservancy is always available to offer free advice and connect to resources, whether or not we hold a preservation easement on their property.”

Tommy Tucker can be reached at Tommy@chestnuthilllocal.com.