Andrews has been rewarded for the way he has handled the job since stepping up from a set-piece coaching position to replace former Bees manager Thomas Frank.
“I’m very proud,” Andrews told the club's website. “It wasn’t long ago that I was signing my first contract so, to be sat here however many months later, that’s probably a good sign!
“It’s felt like it’s gone pretty quick, a lot has happened, but I’m just really proud to get that real vote of confidence from Matthew Benham, Phil Giles, Lee Dykes and Ben Ryan.
“Everyone knows that I’m pretty privileged to be head coach of this amazing club, so to do that for lots and lots more years will be nice.”
Plans for the next six years
Andrews' deal runs to 2032 and he was asked what hopes to achieve over the coming six years.
"I just want to constantly evolve the team and evolve the individuals in the team,” he said. “I want to keep working on that on a daily basis. I want us to keep pushing each other really, really hard.
“Confidence is also such a big part of the game. If the players are in a confident place, you can play them to their highest levels - we’ve shown that pretty consistently.”
The 45-year-old added: “I just want to keep pushing every aspect of our game.
“I want us to be a team that entertains our fans, and one we can look at and feel immense pride in how they go about their business on a daily basis.
“In terms of style of play, I just want us to be relentless; I’ve said that pretty much from the start. We’ve grown and built that.
“I want us to be a horrible team to play against and, in the main, we are. But I also want us to be a team that enjoys playing football and enjoys being a team, not just individuals.”