TVLine got their hands on a casting call for the recurring role, which reportedly describes the character as someone who used to bully young Barry in the schoolyard. Now, Woodward is "a grinning lunkhead who loves destruction," an "unstoppable force… who can transmute any part of his body into solid steel."
In the comics, his powers came from being dunked in molten metal tainted by S.T.A.R. Labs experiments. In the TV series, S.T.A.R. Labs's reactor malfunction (seen in Arrow and then again in The Flash's pilot) is seemingly responsible for all of the metahuman activity in Central City.
Tony Woodward, Girder's real name, joins Plastique, The Weather Wizard and Captain Cold as villains from the comics known to be coming to the TV show.
In a prequel comic released in a special TV Guide distributed at Comic Con International: San Diego last month, Cold was seen playing poker with four other presumed villains, all of whom were hidden in shadows. In the comics, Girder is not a member of "The Rogues," Flash's most recurring group of villains, which includes Weather Wizard and Captain Cold as well as Captain Boomerang, Mirror Master and Pied Piper.
Piper has been widely rumored for the series, since showrunner Greg Berlanti has said that there will be two gay characters introduced in the show and Piper came out during the Wally West era of The Flash.
There's always the outside chance that, like the seemingly self-evident casting call for Blue Beetle that turned out to be The Atom, they're using Girder as a ruse to cast another villain, but given that they're using the character's real name, that seems unlikely.