A huge chunk of what's for sale in Delco was built before anyone had heard of vinyl siding or a central HVAC system. Stone farmhouses out in Edgmont and Concord Township, twins in Ridley Park and Lansdowne, Victorians around Media and Swarthmore, and plenty of Colonials that have been standing since before the Revolution finished. That age is exactly why people want these houses. It's also exactly why they get maintained wrong more often than not.

A 90 year old stone farmhouse and a 1995 colonial are not the same animal, even if a home inspector's checklist treats them like they are. What fixes the newer house can actively damage the older one, and most contractors, even good ones, learned their trade on modern construction. If you own, or are about to own, something built before the Second World War, it pays to know where the differences actually show up.

Old Houses Move Differently Than New Construction

Stone and brick laid before the mid-20th century used lime mortar, which is soft and porous on purpose. It lets moisture pass through the wall and evaporate instead of trapping it. Somewhere along the way, a lot of well-meaning repointing work got done with modern portland cement mortar instead, because that's what's on the shelf at the hardware store. Cement mortar is harder than the stone around it, so instead of the mortar wearing down over time the way it's supposed to, the stone itself starts to crack and spall. Same story with plaster walls versus drywall, and old growth wood windows versus vinyl replacements. The old materials were engineered, even if nobody called it that at the time, for how these buildings actually behave. Swapping in the modern equivalent isn't always the upgrade it looks like.

The Usual Suspects

A few things come up again and again on older Delco homes, especially in the towns with the heaviest concentration of pre-war housing stock, places like Radnor Township, Wallingford, and Edgmont and Concord Township.

  • Masonry and chimneys. Repointing done with the wrong mortar mix, or a chimney that's been relined incorrectly.
  • Wood windows. Original single-pane windows get blamed for drafts that are actually coming from bad weatherstripping, and get replaced when a proper restoration would have kept the historic look and fixed the real problem.
  • Plaster. Cracked plaster over wood lath is a different repair than a hole in drywall, and treating it like drywall usually makes it worse.
  • Roofing. Slate, cedar shake, and standing seam metal all need specialists who know the material, not a standard asphalt shingle crew.
  • Basements and foundations. Older fieldstone foundations were never meant to be sealed up the way a poured concrete foundation is, so some "fixes" trap water where it used to be able to escape.

None of this means avoid an old house. It means know what you're dealing with before you hire the first contractor who answers the phone.

Permits and the Paperwork Nobody Warns You About

A handful of Delco municipalities have historic district commissions or architectural review boards that weigh in before you can change the exterior of a home in a designated historic area, even something as simple as a window replacement or a new front door. The county itself takes this seriously enough that the Delaware County Heritage Commission maintains its own resources for homeowners taking on this kind of project. It's worth a call to your township before you start anything visible from the street, since the rules vary a lot from one town to the next and I'm not going to pretend I know every local ordinance off the top of my head.

Finding Someone Who Actually Knows What They're Doing

This is the part that trips people up the most. The contractor who does beautiful work on a 2010 build in Newtown Square is not automatically the right call for repointing a 1780s stone wall in Thornbury Township (Delaware County). The trades that specialize in this work exist, they're just harder to find than a general search would suggest, which is exactly why Delaware County's own Heritage Commission put together a list of vetted trades and services for historic buildings in the first place.

That same idea is now available at OldHouseDelco.com, a directory specifically for historic home trades and specialists serving Delaware County, searchable by trade and by town. If you're staring down a restoration project and don't know where to start looking, that's exactly what it's there for.

A Few Questions I Get a Lot

Does my house need to be officially registered as historic for any of this to matter?
No. Most of what we've covered here is about the age and construction of the house, not its paperwork status. A 1900 twin with original plaster and lime mortar behaves like an old house whether or not it's on any register.

Will fixing these things the right way actually help my home's value?
Buyers who specifically want an older home tend to notice this stuff. Vinyl windows on a stone colonial or cement stucco over fieldstone can quietly kill the character that made the house desirable in the first place. I can't hand you a dollar figure since it depends heavily on the specific house and buyer pool, but it's rarely a bad long-term call.

Can I just use modern materials since they're easier to find?
You can, but on masonry and plaster specifically, it's one of the more common ways people accidentally create expensive problems down the road. Worth the extra effort to find someone who works in the traditional materials.

I just bought an older home in Delco. Where do I even start?
Get a sense of what's original versus already modified, prioritize anything related to moisture (roof, gutters, grading, foundation) since that causes the most damage over time, and find a contractor who's specifically done historic work before you touch masonry, plaster, or windows.

If you're buying or selling a historic home anywhere in Delaware County and want someone who actually understands what makes these houses different, reach out any time. Curious what your own older home is worth in today's market? Get a free home valuation, or browse the full Delaware County real estate guide.

Licensed Real Estate Agent in Pennsylvania and Delaware | Premier Property Sales and Rentals | 192 Saxer Avenue, Springfield, PA 19064 | 484-442-0295