Can I cut into a container myself?

What you are really asking

The question is almost always practical. You own a grinder, you have a Saturday free, and you want to know whether a shop is worth paying for an opening you could cut yourself.

The deciding factor: does the opening take out structure

A shipping container is stiff because it is a closed steel box. The corrugated walls are not siding, they are a working part of what keeps the box from twisting out of square when it is picked up, set down on uneven ground, or slid off a tilt-bed. The ribs are what let thin panel do that job.

So the test is how much of that panel your opening removes and where. A round hole for a vent sits inside the field between two ribs. It takes out very little and the box is essentially unchanged. A rectangle wide enough to walk or drive through cuts across several ribs at once, and the load those ribs were carrying now has nowhere to go unless you put a path back in for it.

Putting that path back means a welded steel header across the top of the opening and jambs down both sides, so force travels around the hole instead of through it. That is the actual job, and it is why a door is a shop project rather than a weekend one.

What an unframed opening costs you, and when

The trouble with an unframed opening is that it works fine at first. You cut it, you hang something in it, it opens and closes, and the container looks the same as it did. The bill arrives later.

• The box loses some of its resistance to racking, so the next time it is lifted or set on ground that is not flat it can settle slightly out of square.
• Cargo doors are the first thing to tell you. They are hung to close on a square opening, and a box that has moved gives you doors that bind, will not latch, or stop sealing.
• A cut edge that is not dressed and finished is bare steel in the weather, and a sill that does not shed water will stain the wall under it inside a year.
• Wind and watertight is a description of the shell. Once an unsealed opening is in it, that description no longer applies to your container.
• It follows the box. A container with amateur openings is worth less when you sell it and harder to place when you move it.

If the box is rented, stop and call first

A rental container is our steel sitting on your ground, so cutting into one is not your call to make. Same answer if you are renting with the idea of buying it later. In many cases we can credit rent you have already paid toward buying the container outright, but until that is agreed and done, the box is still ours and it needs to come back the way it left.

That is not a no. Our shop modifies containers on rentals all the time, because a mod done properly on a box we own is a box we are happy to take back. Ask us, and we will spec it. The only bad version is the one nobody was told about.

What our shop does with a box you already own

If the container is yours and it is structurally sound and wind and watertight, we can add doors, windows, vents, wiring, racking and finish to it. Bring it to the Woodlawn yard, or on bigger jobs we will quote picking it up and running it back to you when it is done.

We look at it before we quote it, and we will tell you plainly what that particular box can and cannot take. A used container that has already been patched around the rails is a different conversation from a clean one, and we would rather have that conversation before you have paid for a build.