Sheet Metal Weight Calculator

Basic Weight Formula

Weight = Length × Width × Thickness × Density × Quantity

Where all dimensions are in inches and density is in lb/in³

Weight per Square Foot

Weight/sq ft = 144 × Thickness × Density

This gives the weight of one square foot of sheet metal at the specified thickness

Material Densities

Example Calculation

Calculate the weight of a 48″ × 96″ sheet of 14 gauge steel:

• Length = 96 inches
• Width = 48 inches
• Thickness = 0.0747 inches (14 GA)
• Density = 0.284 lb/in³
• Weight = 96 × 48 × 0.0747 × 0.284 = 97.7 lbs

What is the difference between gauge and thickness?

Gauge is a standardized numbering system for metal thickness, where lower numbers indicate thicker metal. Thickness is the actual measurement in inches or millimeters. For example, 14 gauge steel is 0.0747 inches thick. Gauge standards apply primarily to steel; other metals are typically specified by actual thickness.

Which gauge is best for HVAC ductwork?

Common HVAC ductwork uses 26 gauge (residential supply/return), 24 gauge (main trunks), or 22 gauge (commercial applications). Heavier gauges like 20 GA are used for large commercial systems or areas requiring extra durability. The choice depends on duct size, pressure requirements, and local building codes.

Can sheet metal be bent after installation?

While possible, bending sheet metal after installation is not recommended. Sheet metal should be formed and bent before installation using appropriate tools like brakes, folders, or rollers. The minimum bend radius depends on material thickness and type— thinner gauges can be bent tighter. Cold-rolled steel bends better than stainless steel.

What is the minimum bend radius for sheet metal?

Minimum bend radius typically equals the material thickness for soft materials (aluminum, brass) and 1.5-2 times thickness for steel. For example, 16 GA steel (0.0598″) can be bent to approximately 0.090-0.120″ radius. Tighter bends risk cracking or weakening the material, especially with harder metals like stainless steel.

How do I calculate sheet metal area from weight?

To find area from weight: Area (sq ft) = Weight (lbs) ÷ (Thickness × Density × 144). For example, if you have 100 lbs of 18 GA steel: 100 ÷ (0.0478 × 0.284 × 144) = 51.1 sq ft. This is useful when ordering by weight or calculating coverage from scrap metal.

What gauge sheet metal is used for automotive bodywork?

Automotive body panels typically use 18-20 gauge steel. Outer panels (fenders, doors) often use 20 GA for easier forming and lighter weight. Structural areas like floor pans use 18 GA or heavier. Modern vehicles increasingly use aluminum sheet (0.040-0.063″ thick) for weight reduction, especially in hoods and trunk lids.

How is galvanized sheet metal different from regular steel?

Galvanized sheet metal is regular steel coated with zinc for corrosion protection. The base metal thickness is the same as non-galvanized, but the zinc coating adds minimal weight (about 1-2% more). Galvanized metal is essential for outdoor applications, roofing, and HVAC ductwork. The zinc coating requires special welding techniques.

What are common sheet metal forming techniques?

Common forming techniques include: bending (using press brakes or folders), rolling (creating cylinders or curves), stamping (forming shapes with dies), shearing (straight cuts), punching (creating holes), and stretching/shrinking (for compound curves). Each technique has thickness limitations—thinner gauges are more formable while heavier gauges require more force and larger bend radii.