In the Genesis Ark account, the named building material is gopher wood.
Genesis 6:14 instructs Noah to make the Ark from “gopher wood,” a term preserved in many English translations. The original Hebrew word appears only in this passage, so its exact botanical identification is uncertain.
Because gopher wood is a unique biblical expression, proposals have included cypress, cedar, and other durable woods. None of those identifications is established by Genesis itself. “Gopher wood” is therefore the safest canonical answer, while a modern species name would go beyond the evidence of the text.
The same verse separately tells Noah to coat the Ark with pitch. That distinction matters: gopher wood is the traditional name for the construction material, and pitch is the waterproofing substance.