Hey folks, it’s Jake here from your go-to structural steel components supplier—been in this game for 12 years, mostly hanging around heritage restoration sites, so I’ve seen my fair share of folks messing up steel in old building revamps. Today I’m breaking down how we actually use structural steel in heritage projects, the right way, no fancy jargon, just real talk from someone who’s brought parts to 47+ old building makeovers (including that 1892 warehouse in Boston that’s now a fancy co-working space—you’ve probably seen pics). Structural Steel Components
First off, let’s get one thing straight: heritage restoration isn’t like slapping steel on a new office building. You can’t just grab random steel beams from a big-box supply and call it a day. Old buildings have soul—cast iron columns from the 1910s, hand-forged steel lintels that have been holding up walls for a century, and purists on historic preservation boards breathing down your neck if you mess that up. That’s where I come in—my team and I specialize in custom steel components that honor the original vibe without cutting corners on safety.
Let’s start with the basics: why even use structural steel in heritage restoration? A lot of people default to wood or stone, and don’t get me wrong—wood’s great for cabin builds, stone’s perfect for facades. But steel? It’s lightweight, super strong, and way easier to retrofit than you think. We used custom steel angles to reinforce the cast iron columns in that Boston warehouse I mentioned earlier—those original columns were rusted thin in spots, and we couldn’t replace them (historic mandate), so we bolted our slim, custom steel angles right to the outside. No one can tell they’re there, but they added 40% more load capacity—game changer.
Now, the first big step: do your research. Before you even pick up a phone to order steel, dig into the building’s history. Pull up blueprints (most cities have them in their historical society—trust me, I’ve spent 3 weekends in a basement in Philly sifting through 1920s blueprints for a theater revamp). Look at what the original structure was made of. If it’s a 1900s brick building, original lintels were probably soft steel (low carbon) because that’s all they had back then. If you show up with high-strength modern steel, it’ll expand and contract at a different rate than the old brick, and that’s how you get cracked mortar and unhappy preservationists.
Wait, I know what you’re thinking—can’t we just match the specs? Sort of, but not exactly. Old steel has a weird, inconsistent composition. Back in the day, they didn’t have standardized mills, so one beam from 1895 might be 0.25% carbon, another from the same year is 0.3%. Our team tests every original component we get a sample from—we use a portable XRF analyzer that doesn’t even damage the steel, just a quick scan. That’s how we know what to match our custom steel parts to.
Next up: pick the right steel type, and I mean really right. Let’s break down the common ones we use on heritage jobs, no fancy names:
- Mild carbon steel: This is your workhorse. We use this for most custom angles, plates, and connectors when we’re reinforcing existing parts. It’s not too brittle, welds well if we need to add stuff, and matches the expansion rate of most old brick and stone. Just don’t use it where it’ll be exposed to salt air—we have to add a special zinc coating that matches the original rust patina, not the shiny new galvanized look.
- Weathering steel (Cor-Ten, for the folks who know): Wait, a lot of people hate Cor-Ten for heritage because it rusts. But if you use it right? It’s perfect. We used Cor-Ten for the new lintels on a 1930s factory in Cleveland that’s getting turned into lofts. The plan was to have exposed steel, so we treated it to form a stable patina that matched the original exposed steel beams on the upper floor. No more chipping, no more flaking, and it looks like it’s been there since the building went up. Just a heads up—don’t use Cor-Ten where it’ll sit against wood or other steel unless you add a barrier, because the rust stains can bleed.
- Stainless steel: Only use this when you absolutely have to. We reserve it for tiny, hidden connectors—like the bolts holding a new steel beam to an original cast iron column. Stainless is strong, but it’s way more expensive, and it shows. If you put a stainless bolt on the front of a lintel, everyone’ll notice. We always powder coat the few stainless parts we use to match the original steel color anyway.
Now, the fun part: custom components vs. off-the-shelf. I see so many teams go for off-the-shelf steel because it’s cheaper, but on heritage jobs? It’s a trap. Off-the-shelf beams have standard dimensions—like W8x10, that kind of thing. But old buildings have weird, wonky gaps. That Boston warehouse’s cast iron columns were 1/4 inch thicker on one side than the other—off-the-shelf angles wouldn’t have fit. So we cut custom steel plates to exactly match the curve of the columns, welded them to the angles, and it slid right on. No drilling, no forcing, no damaging the original structure.
Another thing: connectors. This is where 90% of the mistakes happen. Old buildings used rivets, right? Yeah, not bolts or welds like we use now. If you weld a new steel part to an original 100-year-old steel beam, you can mess up the original’s strength—heat from welding warps steel, and old steel’s more brittle than new stuff. Rivets are the safe bet, but finding matching rivets? Hard. So we make custom rivet adapters—steel plates that fit over the old rivet holes, so we don’t have to drill new holes (drilling weakens old structures, another no-no). I can’t tell you how many times we’ve saved a project because we made those adapters. The preservation board loved that we didn’t have to modify the original stone or beam.
Wait, let’s talk about disassembly and assessment before you even add steel. A lot of guys jump straight to reinforcing, but you should take a section out first—like a small section of a floor or a wall—to test the original steel. We did that on a 1885 church in upstate New York that needed a new bell tower. We took a 2-foot section of the original steel lintel, tested its strength and composition, and found that it was way weaker than the blueprints said—turns out decades of snow and freeze-thaw had eaten away at it. We added custom steel supports that sat right next to that lintel, so when we put the original back in, no one could tell it was reinforced. That’s the win—you get the safety, you keep the history.
Corrosion is another big one. Old steel’s rusted, and new steel will corrode faster if you put it against old rusted steel. So we always add a barrier—like a sheet of plastic or a zinc-rich primer—between new and old steel. We also blast new steel lightly to get a rough surface for primer, but not so much that we damage the steel. For exposed new steel, we apply a primer that matches the original steel’s finish—if it’s smooth, we smooth ours; if it’s textured, we texture ours. No shiny new steel sticking out like a sore thumb.
Let’s throw in a real example to make this concrete (pun intended). Last year, we worked on a 1922 department store in Detroit that’s being turned into mixed-use. The original steel trusses on the third floor were sagging 3 inches—way too much. The plan was to add new steel trusses, but we couldn’t just put them there because it would block the original skylight, which is a historic feature. So we came up with custom steel tie rods and vertical supports that fit right into the gaps between the trusses. We made the rods the exact same diameter as the original steel rods, and coated them to match. By the time we were done, the sag was down to 1/8 inch—within code—and no one walking through the third floor would guess the trusses were reinforced. The city’s historic preservation commission signed off on it immediately.
Now, a few mistakes I’ve seen people make that you should avoid at all costs:
- Using too much steel: Don’t over-engineer it. Just because you can make a beam super strong doesn’t mean you have to. Excess steel looks out of place, and it’s unnecessary. We calculate exactly what load the original structure can hold, then add 15-20% extra to account for future use—no more, no less.
- Not getting sign-off early: Preservation boards hate surprises. Send them your plans for custom steel components before you order anything. We always provide mockups—small test pieces of the steel we’re using—so they can see how it’ll look. 9 times out of 10, they love it, because we’re not trying to hide what we’re doing, just respect the original.
- Using the wrong coating: I touched on this earlier, but it’s worth repeating. Don’t use bright galvanized steel for exposed parts. It looks like a construction site, not part of a historic building. We use patina coatings for Cor-Ten, matte powder coat for mild steel, and match the exact color of the original steel—even if that means mixing custom paint.
One last thing: sustainability. A lot of heritage projects are focused on going green, and steel’s one of the most recyclable materials out there. We use 100% recycled steel for all our custom heritage components. That’s a big selling point right now—clients love that they’re not just saving a building, they’re reducing waste. We even take scrap from the site back to our shop to reuse, so nothing goes to landfill.
If you’re working on a heritage restoration project and need structural steel components—whether it’s custom angles, plates, connectors, trusses, whatever—hit me up. We work with contractors, architects, and preservation groups all over, and we make every part to fit exactly what you need, while keeping the historic look intact. We’re not just a supplier—we’re guys who’ve done hundreds of these jobs, so we can walk you through every step, from testing the original steel to getting sign-off from the preservation board.
Don’t waste time with off-the-shelf steel that doesn’t fit, or parts that ruin the building’s history. Let’s make your heritage project strong, safe, and true to its roots.
Fasteners References:
- National Park Service. (2017). Standards for Rehabilitation: Historic Structures. U.S. Department of the Interior.
- American Institute of Steel Construction. (2020). Steel Construction Manual for Historic Preservation Projects. AISC.
- International Code Council. (2021). 2021 International Existing Building Code. ICC.
- Historic Preservation Society of America. (2019). Guide to Structural Repairs for Historic Buildings. HPSA.
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