Usually far less than people expect. Steel conducts, so a strike tends to run around the outside of the shell and into the ground rather than through the middle of your load. What decides the outcome is what is bonded to the box: wiring run inside, a metal building beside it, or a mast on the roof.
Three separate worries hide inside this question and they want three different answers. Whether a ridge that takes a strike every August is a fair place to set a steel box. Whether what goes inside it is at risk. Whether protection is worth buying before you load it.
The steel is the easy part in all three. What actually decides the outcome is whether anything conductive runs from the box to somewhere else: a power drop, a data line, a bonded metal building, a bracket on the roof holding an antenna. A bare steel box standing alone is a very different problem from a wired one.
A closed, welded steel shell is one continuous conductor. Current that lands on it spreads across the skin and heads for the shortest route down, which is the corner posts, the castings, the blocks and the ground. It does not need to route through the middle of the box to get there, and the contents are not in that path.
That is the same reason a car is a reasonable place to be in a thunderstorm, and it is why a container shell handles a strike better than a wood-framed shed. The 14-gauge weathering steel is thick, it is welded rather than screwed together, and it has nothing in it to catch.
What you may see afterward is cosmetic: a scorch mark, paint burned back, a small pit where the arc attached. Steel that thick does not vanish. It is worth a look at the roof and the seams after any close strike, but on most of them there is nothing to find.
Every failure worth worrying about here is an electrical one, and it follows a wire. The usual paths:
If none of that describes your box, there is very little left to damage. If some of it does, the fix is ordinary electrical practice: surge protection at the panel that feeds the run, and a proper ground, both handled by a licensed electrician who knows the site.
Lightning goes for height and for a good path to ground. A container is 8 feet 6 inches tall, or 9 feet 6 inches on a high-cube, which is short next to a mature oak, a silo, a pole or a barn roof. On most properties around here the box is not the tallest thing in the field, and that is worth checking before you spend on anything else.
Two things do work against you. A bald knob or open pasture where the container is the tallest object for a hundred yards, and a low, wet spot, since saturated ground under the box is part of the strike path and is also the ground that rusts crossmembers and keeps the floor damp. Our foundation guide covers the drainage side of that, and it happens to be the same advice.
We do not install lightning protection, we do not ground containers as a service, and we would not know how to price a protection system honestly if we tried. That is a licensed electrician's work, on your site, with your service in front of them.
Our fab shop does rough in electrical on containers we modify: panel, outlets, switches, conduit. The final hookup and the inspection are done by a licensed electrician, and we do not pull permits for it. That boundary is not a hedge, it is where our trade stops and theirs starts.
What we can do is talk through the spot with you before the box ships. Call (276) 237-6144 and tell us what is on the property, what is going in the container, and whether it is getting power. That is usually a five minute conversation that saves a longer one later.
Power, exposure, what you are storing. A short call settles what your site actually needs before delivery day.
Same-day reply. We'll send a real number, a real delivery window, and any photos we need to confirm fit.
You'll hear back from us today (or first thing tomorrow if it's late). For anything urgent, call (276) 237-6144.