How to Use the Expanded Metal Weight Calculator
Expanded metal (metal lath) is made by slitting a solid sheet and stretching it into a diamond mesh, commonly used for plaster lath, ventilation guards, and walkway treads. Because material is removed and redistributed rather than kept solid, a flat-sheet weight formula alone won't give you the right answer.
A solid sheet weighs thickness (in) × 40.83 lb/ft², but expanded metal is lighter than the equivalent solid sheet because of its open diamond pattern. This calculator applies a style-specific open-area allowance — light (about 60% of solid weight remains), standard (about 68%), or heavy (about 75%) — to get the unit weight, then multiplies by area for total weight.
Keep in mind that actual open area varies 5-10 percentage points depending on SWD (short way of design), LWD (long way of design), and strand width, so this is an estimating tool rather than an exact spec match. For firm order weights on a construction project, check the manufacturer's published weight table for the exact product designation.
Frequently Asked Questions
It's made by slitting and stretching a solid sheet into a diamond mesh, so the open (cut) areas remove material compared to the same footprint of solid sheet. Depending on style, roughly 60-75% of the solid-sheet weight remains.
This calculator uses an average open-area allowance per style, so it's an estimate. For firm order weights, check the manufacturer's published weight table by SWD (short way of design), LWD (long way of design), and strand width.