October 28, 2026 · Indumor
A Steel: shop work and foundations in parallel · B Concrete: one stage after another.
A steel building can be taken apart and put up again on another site.
A brick one can't, and that difference explains most of what there is to know about steel construction. The structure is a skeleton of members made in a shop and brought to site to be bolted or welded together, and both its strengths and its weak points come from there. Here they are one by one, told twice, once as the theory puts it and once as we see it in our shop and on site.
The theory. While the foundations are dug and poured on site, the columns are being cut and welded in the shop. Both run in parallel, and by the time the concrete is ready the frame is painted and waiting for the truck.
In the shop. That holds as long as the drawings are frozen before work starts. The usual delay is not the steel but a dimension that changes halfway: if the door moves half a meter, the plates and holes of the columns on that side have to be redone. On a masonry job that change gets sorted out on site, with a trowel. In steel, it goes back to the shop.
Steel is fast for people who have already decided.
The theory. Steel is very strong for its weight, so it spans long distances without interior columns and needs smaller foundations. A 15 × 30 m building (about 50 × 100 ft) like the one we worked out for another guide takes around 4.5 tonnes of structure, roughly 10 kg per square meter of floor, or 2 lb/ft².
In the shop. Light weight has a side people forget, and that is wind. A sheet-metal roof is more likely to blow off than to cave in, and in an open shed the air coming in from below pushes up. If the footings are too small, the whole frame can lift. That is why the foundations of a steel building are designed as much against uplift as against settlement.
The theory. Carbon steel rusts in humid air, so it needs paint or galvanizing, plus some maintenance every few years depending on the environment.
In the shop. Rust rarely starts in the middle of a beam. It starts where water collects, at column bases buried in the floor slab or in the hole someone drilled on site after painting. A column embedded in the slab can lose thickness at the bottom for years without anyone noticing. With a well-detailed column base and touch-ups done on time, a frame under roof lasts for decades.
The theory. Steel does not burn, but it loses strength as it heats up. According to the Eurocode for steel structures in fire, at 600 °C it keeps less than half of its yield strength, and at 700 °C less than a quarter. An unprotected frame can deform in a long fire.
In the shop. How much protection you need depends on the use, on what is stored inside and on the local code, and a machinery shed is nothing like a warehouse full of combustible goods. Find out before asking for a price, because intumescent paint, which swells with heat and insulates the member, costs a good deal more than ordinary paint and changes the quote.
The theory. A kilo of steel is expensive, but you use few of them, and the savings in time and foundations make up for it.
In the shop. It depends a lot on the job. On a building with long spans steel usually wins; on a small building with lots of walls, masonry can come out cheaper. Within the price of the frame, labor weighs as much as material, and twenty identical columns are much faster to make than twenty different ones. A design that repeats members pays off.
If you are weighing options for a project, send us the dimensions and the use. At Indumor we will quote the steel frame with the weight of each part, and our steel construction page shows everything we build.
Send us the size and the use, and we will quote the steel frame with its member list.
© Indumor 2010–2026 — Industrial steel fabrication, Córdoba, Argentina
