Three Surprises on a Historic Home Siding Project, and How We Changed Our Pre-Construction Process
Older homes rarely play by modern rules. Walls settle, rooflines shift, and additions get bolted on in ways no blueprint ever accounted for. On a recent siding project on a historic home in Middletown, MD, that reality caught up with us three separate times — twice during our pre-construction site visit, and once after the walls were already open. We’re sharing this because it’s a story that may inform homeowners with historic properties, and because it says more about our process than any “About Us” page could.
A home’s age and history can hide details that matter — before you sign anything, it’s worth having someone look in person.
Why Older, Out-of-Square Homes Change the Math on Siding
The original quote included soffit cladding for a large overhang at the roofline. What didn’t get factored in during the sale: on a home this age, that overhang wasn’t square. It had settled unevenly over decades, the way most pre-war construction does.
That matters more than it sounds like it should. Flat panel materials need a true, even plane to lie flat. Install them over an out-of-square surface and you get oilcanning — a rippled, wavy look where the panel can’t lie flush. It’s not a defect in the material. It’s a mismatch between the material and the substrate.
This is where our pre-construction site visit did exactly what it’s supposed to do. Before any material was ordered or installed, our project manager walked the home in person, measured the overhang, and flagged the squareness issue. We adjusted the plan before it became a problem on the roof.
What Our Project Manager Found Before Demo Ever Started
The second issue turned up the same way: during that same pre-construction visit, before a single piece of old siding came off. Our PM identified that the sheathing underneath the existing siding was likely going to need replacement before new siding could go on — something that hadn’t come up anywhere in the original estimating conversation.
This is exactly why that pre-construction visit exists as a required step in our process, and not an optional courtesy call. A trained set of eyes on the actual home, before demo starts, is what turns “we hope everything underneath looks fine” into “here’s what we’re actually dealing with, and here’s the plan.” In this case, it worked — the homeowner knew about the sheathing before a single wall was opened, instead of finding out mid-project.
A Question We Asked Three Times — and Still Got Wrong
Before work began, we asked the homeowner more than once whether there were any shower benches or fixtures on the exterior walls. Each time, the answer was no. Once we opened up the wall, there were several.
We’re not sharing this to shift blame — homeowners aren’t always the ones who’d know this detail, especially in an older home with additions or renovations by previous owners. We’re sharing it because asking a question and getting an answer isn’t the same as verifying it, and on a project like this, that gap can turn into a real delay or a real cost once walls are already open.
What We're Changing About Our Process
None of these were disqualifying problems — the project got finished, and it got finished correctly. Two of the three were caught before they ever became a real issue, because our pre-construction site visit did its job. That visit exists precisely so a trained project manager sees the actual home — not a photo, not a description — before demo starts, and this project is a good example of why that step earns its place in our process.
But two out of three surprises being caught at pre-construction, rather than zero out of three being surprises at all, is still room to improve. Here’s what’s changing:
- Rooflines and overhangs on older homes now get evaluated for squareness during the estimate, not left to be caught at pre-construction. If a surface isn’t true, that gets discussed — and priced — before a homeowner ever signs.
- Sheathing condition is now raised directly in the sales conversation on older homes, framed as a realistic possibility rather than something that surfaces later, so homeowners have that expectation from the first conversation, not just by the time our PM confirms it.
- Exterior fixtures and features are now confirmed with a physical walk-around, not just a verbal question-and-answer, especially on homes with a renovation history the current homeowner may not fully know.
- The pre-construction visit stays in place as the safety net it’s meant to be — but the goal is for it to confirm what’s already expected, not introduce it for the first time.
If Your Home Is Older or Has an Irregular Shape, Here’s What to Ask
If your home has an addition, an irregular roofline, or a renovation history you’re not 100% sure about, ask your contractor directly: how are you checking for squareness on my overhangs? Have you priced in the possibility of sheathing repair? Are you physically walking the exterior, or just asking me what’s out there? Good answers to those three questions tell you a lot about how a project is actually going to go.
We’ll walk your home in person — overhangs, old fixtures, and all — before you commit to anything.
FAQ: About Historic Home Siding Project
What can go wrong on a historic home siding project?
The three most common surprises on a historic home siding project are out-of-square surfaces, deteriorated sheathing hidden behind the old siding, and undocumented fixtures inside exterior walls. On a recent project in Middletown, MD, we ran into all three. Older homes settle, get renovated, and gain additions over decades, so what’s behind the siding rarely matches the original plans or what the current homeowner knows.
Why does it matter if an older home isn't square?
Flat panel siding and soffit materials need a true, even surface to lie flush. When they’re installed over an out-of-square overhang or wall, the panels can’t sit flat and the finished exterior looks wavy. Most pre-war homes have settled unevenly over time, so squareness needs to be measured and planned for before any material is ordered or installed.
What is oilcanning on siding?
Oilcanning is a visible rippling or waviness in flat siding or soffit panels. It isn’t a defect in the material itself. On older homes, it usually happens when panels are installed over an uneven or out-of-square surface, which creates a mismatch between the material and the substrate underneath it.
Will my historic home need new sheathing before new siding goes on?
It’s a realistic possibility. Sheathing is the layer underneath your siding, and on older homes it may have deteriorated over decades without any visible sign from the outside. At American Custom Contractors (ACC), we now bring up sheathing condition in the first sales conversation on older homes, so it’s part of your expectations and budget from the start rather than a mid-project surprise.
What is a pre-construction site visit, and why does it matter?
A pre-construction site visit is a required step in our process where an ACC project manager walks your home in person, takes measurements, and checks conditions before materials are ordered or demolition begins. On our Middletown historic home siding project, this visit caught two of the three issues, an out-of-square overhang and likely sheathing replacement, before a single piece of old siding came off.
Why should a contractor physically walk my home's exterior instead of just asking questions?
Homeowners don’t always know what’s inside their walls, especially when previous owners added rooms or renovated. On our Middletown project, we asked the homeowner three times whether there were shower benches or fixtures on the exterior walls. The answer was no each time, but once the wall was opened, there were several. Asking a question isn’t the same as verifying the answer, so we now confirm exterior fixtures with a physical walkaround.
How has ACC changed its process for siding older homes?
We made four changes after this project. Rooflines and overhangs on older homes are now evaluated for squareness during the estimate. Sheathing condition is raised directly in the sales conversation. Exterior fixtures are confirmed with a physical walkaround instead of a verbal check. The pre-construction visit stays in place as a safety net, with the goal of confirming what’s already expected rather than discovering it for the first time.
What should I ask a contractor before starting a siding project on an older home?
Ask three questions: How are you checking for squareness on my overhangs? Have you priced in the possibility of sheathing repair? Are you physically walking the exterior, or just asking me what’s out there? A contractor with clear, specific answers to all three is far less likely to hit costly surprises once your walls are open.
Does ACC work on historic homes outside Middletown, MD?
Yes. American Custom Contractors is a family-owned exterior remodeling company founded in 1972 and licensed in Maryland, Washington DC, Virginia, West Virginia, and Pennsylvania. We walk every home in person, including overhangs, old fixtures, and areas affected by past renovations, before you commit to anything.
