The Hammers' starting line-up in Saturday's 1-0 win over Peterborough featured just five players - Robert Green, Winston Reid, Julien Faubert, Mark Noble and Carlton Cole - who were in the team relegated last season.
Allardyce's revamped side, including summer signings such as Matt Taylor, Joey O'Brien, Henri Lansbury and new skipper Kevin Nolan, are now unbeaten in their last seven games ahead of Tuesday's clash with Ipswich.
"The players have built a very good dressing room very quickly," said Allardyce.
"That's down firstly to the captain and then the rest of the players joining in and building a unity between them that's a good bond, so they can enjoy their own company.
"That's what we are building and that's helped us get good results on the field."