The Steel Erector's Pre-Mobilization Checklist: What to Review Before Iron Hits the Site

Every steel job I've ever walked onto that went sideways had one thing in common: nobody did a real pre-mobilization walk before the crane showed up. Not a phone call. Not a set of drawings emailed back and forth. An actual person, on the actual site, checking the actual conditions against what the erection plan assumes. Skip that step, and you're betting the whole schedule on the drawings being right and the site matching the survey. In 35-plus years on the iron, I've learned that bet doesn't pay off nearly as often as people think.

Here's what I actually check before I'll sign off that a site is ready for steel.

Concrete cure and anchor bolts

Under 29 CFR 1926.752(a), the controlling contractor has to give the erector written notification that footings, piers, and walls have reached at least 75% of their minimum compressive design strength before any column goes up — verified by field-cured sample testing, not a guess. I ask for that notification in writing every time, and I physically check the anchor bolts myself: projection height, thread engagement, template alignment against the base plate holes, plumb, and grout bed level. If any anchor bolt has been repaired, replaced, or modified, OSHA requires that change be approved by the Structural Engineer of Record before erection proceeds — and I want to see that approval on paper, not hear "yeah, it's fine" from someone on-site.

Site access, staging, and ground conditions

I walk the access roads, the laydown area, and the crane pad before I'll trust any of it on paper. OSHA's crane standard (29 CFR 1926.1402(c)) puts the responsibility on the operator and employer to make sure ground conditions are adequate to support the crane and the load throughout the lift — not just at setup. That means checking for soft spots, buried utilities that could give way under outrigger pressure, and whether the laydown area is actually graded, drained, and accessible the way the site plan assumes. I've seen more schedule delays caused by a crane pad that turned to mud after a rainstorm than by any design error.

Overhead and underground utilities

Power lines get checked for minimum approach distance before the crane ever picks anything — this isn't optional, and it's one of the most common causes of fatal crane incidents on record. Underground utilities get verified through a proper one-call locate, not assumed from an old site drawing. Both get walked and marked before mobilization, not discovered mid-lift.

Erection sequence and drawing conflicts

This is where I earn my keep. I cross-check the erection sequence in the plan against what's actually buildable on this site — crane reach at each pick point, temporary bracing and stability requirements at every stage, and whether the connection details in the shop drawings actually match the structural drawings. If there's a conflict, I want it resolved before the first piece of steel leaves the yard, not discovered when a beam is already hanging and doesn't line up.

Communication and sign-off

Every site-specific erection plan should get reviewed at a pre-construction conference with the GC, the erector, and anyone else affected — and it should carry a signature, not just a "looks good" in an email thread. I want every worker on that crew to have actually reviewed the plan, not just been told it exists.

Why this matters more than it looks like it does

None of this is complicated. It's also almost never done thoroughly, because everyone assumes someone else already checked it. The controlling contractor assumes the erector will catch problems. The erector assumes the drawings are accurate. The crane operator assumes the ground was verified. By the time steel is on site and the crane is mobilized, catching a problem doesn't save you money anymore — it costs you a stopped crew, an idle crane, and a schedule that's now behind before it started.

A pre-mobilization site assessment isn't a formality. It's the cheapest insurance you'll buy on the entire project, and it only works if the person doing it has actually spent time in the field — not just read the plans.

That's the review Iron Strength Solutions runs before your crane rolls in. We check the site, the sequence, and the sign-offs against 35-plus years of having been the crew standing under the load when something wasn't checked. Our Field Risk Review and Constructability Review cover exactly this ground, and our Crane & Lift Access Review makes sure the crane can actually do what the plan assumes it can.

Request a quote and let's walk your site before the iron shows up.