Etabs Mass Summary By Story -

The "Where is my Mass?" Mystery Here is the most common panic moment for engineers: "I assigned a 10-inch slab, beams, columns, and walls... so why does the Mass Summary show almost nothing on the roof?"

If you’ve ever run a seismic analysis in ETABS, you’ve probably scrolled past the Mass Summary by Story table. It looks harmless enough—just a few columns of numbers under the Display > Show Tables > Analysis > Results > Structure Output menu. etabs mass summary by story

If you modeled a concrete slab but forgot to assign Self Weight Multiplier = 1 (under ), ETABS will only include the superimposed dead loads (finishes, partitions) and completely ignore the 150 pcf concrete you just modeled. The "Where is my Mass

In fact, most convergence errors, unexpected mode shapes, and even incorrect base shears can be traced back to a single misunderstood line in this table. If you modeled a concrete slab but forgot