"Losing Libor was a blow to us, obviously," said Lambert.
"When I knew Grant had become available it was something I wanted to pursue quickly because he'll add strength and experience to what is still a young squad overall.
"Having worked with him for three years at Norwich, I know what he can do and that's important.
"Coming back into the Premier League will rekindle that desire in him to succeed again at this level and, if he can replicate what he did in those three years at Norwich over these next few months here at Villa, then he'll make an impact, that's for sure.
"Grant's got some really strong attributes, he's someone who is tried and trusted and a player I've worked with before.
"We're looking at one or two other positions as well but this is good business for us and he'll be a really strong influence."