Properties for the stuff that actually gets built with: hull aluminum, mild and alloy steel, stainless, concrete, framing lumber, machining plastics, and FDM filaments as-printed. Wood and prints are anisotropic and the data says so instead of pretending otherwise.
Source of truth: /data/materials/materials.json, validated by schema.json.
This page renders the same JSON your Grasshopper script should read.
Confidence and basis are encoded in the data, not in tribal memory.
how to read this
basis -- not all numbers are the same kind of number. typical representative handbook / datasheet values. spec min ASTM certified minimums; real material tests higher. NDS design wood allowable design values, roughly 2–3× below ultimate, adjustment factors still apply. f'c concrete specified 28-day compressive strength, stiffness derived per ACI 318. Comparing a wood allowable against a metal typical without noticing is how people conclude PLA beats Douglas fir.
anisotropy -- a split value means the material is direction-dependent. Wood: ∥ parallel / ⊥ perpendicular to grain (orthotropic). FDM prints: XY in the layer plane / Z across layer bonds (transversely isotropic). The strong direction is listed first; the dim hatched bar is the weak one. Click any row for the full story, including the one-number-breakers that aren't directional: concrete's tension asymmetry, nylon's moisture swing, 6061's weld knockdown.
FDM entries are as-printed (100% infill, quality-TDS-class values), not bulk polymer. Expect ±20% across brands and process. Prices are order-of-magnitude retail, for ranking only.