Old-growth lumber rescued from demolition — embodied carbon is already paid; the building stores it again.

This material screens clear across all seven independent toxicology authorities we use on every project.
Reclaimed wood is solid timber pulled from buildings, barns, factories, and infrastructure at end of service life, then re-milled for a second use. The advantage is twofold: old-growth wood tends to be denser, more dimensionally stable, and more rot-resistant than modern fast-growth lumber, and the embodied carbon was paid generations ago — keeping that wood in the building stock continues to store the carbon rather than releasing it through demolition combustion or landfill decomposition. The caveat is testing: pre-1990 utility-pole, railroad-tie, or industrial stock may have been treated with CCA arsenic, pentachlorophenol, or creosote. EBH only uses reclaimed wood with documented provenance and lab-tested heavy-metal / chlorinated-phenol clearance.

Severity scored 0–10 against the same 10 hazard endpoints we use for the chemical families on the avoid list. Every score is 1–2 — essentially no signal across every endpoint.
Listed alphabetically. Where in a home this material earns its keep.