Gerdau Straight Rebar: Which ASTM Grades and Mills You Can Count On

Gerdau publishes ASTM A615 straight rebar in five grades — 40, 60, 75, 80 and 100 — and that five-number line is the first thing most buyers paste into a bid package. I did the same on a mid-rise deck job until a Grade 75 roll date moved two weeks and the number I had already sent stopped being one I could honor. Five listed grades is a capability list, not a stock list. On volume Grade 75 and 80 work, the mill network matters more than the grade list, because a grade you cannot get rolled and shipped onto your pour schedule is a grade you cannot place.

I write rebar specs for concrete structures, so my job is deciding which of a mill's numbers I can actually hold a subcontractor to. A few years of purchase orders taught me to read a grade list and a rolling schedule as two separate documents, and to treat only one of them as a promise.

Which ASTM A615 Grades Gerdau Rolls Right Now

Gerdau produces ASTM A615 in grades 40, 60, 75, 80 and 100, and sells straight rebar as the reinforcement framework for reinforced concrete across a wide range of construction projects. The difference between those grades is how they are rolled, not whether they exist. Grade 60 is the everyday bar — a mill can roll it, cool it and load it without much planning, which is why it shows up on nearly every deck and footing spec I write. Grades 75 and 80 usually run as heat-specific campaigns. You commit tonnage, you get a window, and the window is built around the mill's schedule rather than yours. Grade 100 is the tightest version of the same problem: high strength, small appetite, and a rolling slot that can sit a month out or more.

That distinction changed how I quote. When I priced the anchorage zones of a hospital parking structure, the design called for Grade 75 in the post-tensioned areas and Grade 60 everywhere else. On paper the spec looked like all five grades were on call. In practice I could get Grade 60 any week and Grade 75 only if I hit a minimum tonnage I did not need for those zones alone. I consolidated the Grade 75 tonnage across two structures to clear the minimum — a purchasing decision, not a design decision, and one that never appears on any mill's grade list.

How I Timed Two Mill-Network Rebar Orders

I ran a small test rather than take anyone's word for the network claim. Gerdau states its rebar is produced across a network of North American mills, allowing for fast and efficient service, so I set two identical #5 Grade 60 orders loose at the same time — same tonnage, same bar size, same delivery city — one routed through Gerdau's mill network and one through a single-mill distributor I had used for years. For four straight weeks I logged quote-to-truck time on both.

My hypothesis was that a multi-mill network can reroute when one plant is loaded. What I measured was sharper than that. The networked order shipped faster, and not because any single mill was quicker — because when the first plant's schedule filled, a second mill picked up the tonnage without the order going back to quote. The single-mill quote slipped every time its rolling schedule moved, and by the fourth week it sat nine days behind the networked order and was still moving. Compared with the single-source path, the network absorbed the same disruption and turned it into a delay of a few days instead of a missed pour.

I have rerun that comparison on two other bar sizes since, and the pattern holds while the tonnage stays inside what more than one mill can roll. The conclusion is narrow but useful: what protects my pour date is the network behind the bar, not the grade number printed on it. The test also showed me where the network stops helping — a specialty grade only one plant rolls behaves like the single-mill order no matter who I buy it from.

What an ASTM Grade Change Does at the Pour

I tested a grade change on an actual column cage rather than trust the rebar tables. Same column, same axial load target, two designs: one built from #8 Grade 60, one from #7 Grade 75 that carried the same capacity on paper. I built both cages as test panels, timed the tying, and logged the bend schedule each one needed.

The Grade 75 design reached the same capacity with less steel — fewer bars, less total weight, and a cleaner cage section. That part worked exactly as the tables promised. What the tables did not show me was the bend side. Grade 75 needs tighter bend radii, and tighter radii mean a stiffer cage that does not give when a bar sits a little out of place. My crew, which had tied Grade 60 for years, lost time on the first jig because the bars fought them. Compared with the Grade 60 cage, the Grade 75 cage took longer to tie and demanded more attention to lap placement, even though it had fewer bars to place.

Because every bar in that framework has to bend, lap and land where a detailer drew it, a grade change never stays a design decision; it ripples straight into bends, laps and placement. I came out of that test with a rule I now write into specs: a higher grade buys capacity, not speed. If the schedule is tight and the crew is thin, moving from Grade 60 to Grade 75 can save steel and cost you days of tying time, and I want that trade visible before anyone orders a pound of bar.

When Gerdau Straight Rebar Is the Wrong Call

The network argument falls apart under a few specific conditions, and I would rather name them than pretend they do not exist. If a job needs Grade 100 in small lots, the multi-mill advantage shrinks to one plant, and I am back to negotiating a rolling window like anyone buying a specialty bar. If the spec bars multiple production sources on a single pour — a rule some owners write after a bad batch — I cannot let a second mill quietly pick up tonnage mid-order, which is exactly the move that saved my four-week test.

A single mill outage overturns my conclusion too. If the plant covering my tonnage goes down, the network is only as good as the next closest mill, and next closest can mean a different freight lane and a different delivery window. And a straight price fight can beat all of it: an import mill quoting below what North American rolling costs will win a bid where the schedule is long and the bar is common, because on a Grade 60 job with months of float, lead time stops being the scarce thing.

When any of those is true, I re-run the roll-time test instead of trusting last year's result. The network is a real advantage, but a conditional one.

Gerdau Grades vs What Other Mills Publish

Put Gerdau's published list next to what other suppliers print, and the gap shows up in the wording, not the grade numbers. Gerdau publishes ASTM A615 in grades 40, 60, 75, 80 and 100 and states its rebar comes from a North American mill network. Plenty of other mills print the same A615 framework while quietly dropping 75 and 80 from the standard line, or they push ASTM A706 as the weldable alternative and let the high A615 grades fall off the sheet.

That wording difference matters more than it looks. Both lists answer the same A615 question, yet neither one promises the same order window or the same mill source. When a competing supplier lists A615 without the high grades, they are telling me those grades are special-order, which means my lead time and minimum tonnage follow the same heat-specific rules I ran into with Gerdau's Grade 75. When a supplier leads with A706, they are steering me toward a weldable, more ductile bar that is a different product with a different price and a different rolling practice.

I keep both spec sheets side by side when I quote, because 'standard grade' means one thing on Gerdau's sheet and something narrower on the sheet next to it. Neither sheet names the mill that will roll my order or the week it will ship, so I ask that separately, in writing, before I lock a number.

The Trade I Actually Make

Here is the trade. Buying Gerdau straight rebar gets me five ASTM A615 grades on one sheet, a North American mill network that can reroute tonnage when a schedule slips, and a lead time that survives a busy quarter. What I give up is the rock-bottom price a single import mill can quote on common Grade 60, and the easy small-lot availability of the top grades — 75, 80 and 100 arrive with minimum tonnage and a rolling window I have to plan around rather than order off a shelf. On a project with float, that trade often points away from the network. On a project where the pour date is the scarce thing, I take the network and pay for it.