He had found first-team opportunities limited at Villa this season and becomes Alex McLeish's second signing of the current transfer window following former Sporting Gijon midfielder Michel.
Related ArticlesSpirited Birmingham dispatch EvertonEverton 1 Birmingham City 2Birmingham close on Craig Gardner dealKris Boyd future unclearBirmingham offer £14m for McGeadyPremier League Transfer Talk"I'm over the moon especially being at the club I supported as a boy," Gardner said. "I just can't wait to get out there, put the shirt on and do well for the club. I have not slept properly for the last three or four days waiting until the deal to be done. Now it's done it's unbelievable."
Gardner is not expected to be the last addition to Birmingham's squad this month. McLeish is looking to sign a new striker this week. He will not be rushed, however, into making any rash signings.
'I think it is important [to perform due diligence] because you can buy a South American and you might not know exactly what you are getting,' said McLeish. 'We've been recommended hundreds, there's a scatter-gun effect with the names I've had.
'There's been emails, phonecalls - it really is an absolute frenzy, ridiculous, I've got to say. It's partly because people are aware we have a few bob and maybe a lack of deals because they're all trying to make a few quid.
'Six guys have given me a single player for instance. They said, 'I've got an exclusive mandate', so there's exclusive mandates being handed out everywhere and I don't want to bring in a player who I don't know, who I've not heard of.
'I would think that Messi would be all right, somebody like that, household names yes. But I don't want to bring in a foreign player I don't know."