--- title: "12 gauge steel: Definition and Meaning | NPSA" description: "12 gauge steel is steel sheet about 0.1046 inch (2.66 mm) thick on the standard steel gauge scale." url: https://npsa.preview.multisites.ai/glossary/12-gauge-steel publisher: National Portable Storage Association (NPSA) phone: "(816) 960-6552" email: info@npsa.org --- Materials and construction # 12 gauge steel 12 gauge steel is steel sheet about 0.1046 inch (2.66 mm) thick on the standard steel gauge scale. Gauge numbers run backward, so 12 gauge is thicker than 14 gauge. Some portable storage makers list 12 gauge sides, as the NPSA containers page does. ## Why it matters Gauge is a traditional, non-linear way to state sheet metal thickness. The larger the number, the thinner the metal. A 12 gauge sheet is about 0.03 inch thicker than 14 gauge, which adds strength and weight. NPSA's own container page mentions both 12 and 14 gauge sides for portable storage containers. A common mistake is to compare gauge numbers across different metals. Steel, aluminum and copper use different tables. Another is to accept a gauge claim without asking where it applies. A unit may use one gauge for the walls and another for the doors, floor parts or frame. Ask the maker for the gauge by part. [Read: Container modifications for rental: Doors, windows, lock boxes and HVAC](https://npsa.preview.multisites.ai/guides/container-modifications) Definition source: [en.wikipedia.org](https://en.wikipedia.org/wiki/Sheet_metal) ## Related terms [### 14 gauge steel 14 gauge steel is steel sheet about 0.0747 inch (1.9 mm) thick on the standard steel gauge scale. Many sources name 14 gauge corrugated corten steel for the walls and roof of a standard shipping container. Actual builds can vary by maker.](https://npsa.preview.multisites.ai/glossary/14-gauge-steel)[### corrugated steel Corrugated steel is sheet steel pressed into a pattern of ridges and valleys. Shipping containers use it for the walls and roof. The ridges add stiffness, so a thin panel resists bending and racking forces during ocean transport, lifting and everyday handling.](https://npsa.preview.multisites.ai/glossary/corrugated-steel)[### corten steel Corten steel is a weathering steel alloy used for the walls and roof of most standard shipping containers. It contains copper and chromium. When it is exposed to weather, it forms a stable, rust-like surface layer that protects the metal below. COR-TEN began as a trademarked name.](https://npsa.preview.multisites.ai/glossary/corten-steel)[### tare weight Tare weight is the weight of an empty container or vehicle. Subtract it from the gross weight to find the weight of the goods inside. On a shipping container, it is not set by the ISO standards. It depends on how the container was built.](https://npsa.preview.multisites.ai/glossary/tare-weight)[### container modification A container modification is a change made to a standard shipping container. It covers a single door cut-in up to a full fit-out. Common changes include doors, windows, vents, insulation, electrical work, HVAC, lining, partitions and plumbing. Sellers often group these changes into packages.](https://npsa.preview.multisites.ai/glossary/container-modification)[### payload Payload is the weight of cargo a container can carry. It equals the maximum gross weight minus the container's own empty (tare) weight. Carrier specs list payload next to tare weight for each container size and type, so buyers can compare them side by side.](https://npsa.preview.multisites.ai/glossary/payload) [All 220 terms](https://npsa.preview.multisites.ai/glossary) For the industry ## Grow your portable storage business with NPSA Members get event rates, the Community Forum, the directory listing and leads from this website. [Join NPSA](https://npsa.preview.multisites.ai/join-us)[See member benefits](https://npsa.preview.multisites.ai/member-benefits) Need storage? ## Get quotes from NPSA member companies Tell us what you need and where. A member company that serves your area will contact you. [Request a quote](https://npsa.preview.multisites.ai/request-a-quote)[Which unit do I need?](https://npsa.preview.multisites.ai/find-storage)