Edinburgh revived memories of their sensational run to the semi-finals of the competition in 2011-12 when they beat Munster 29-23 in the opening round of this season's tournament. However, their hopes of reaching the last eight took a dent when they lost away to Perpignan the following weekend, and Laidlaw believes that a win on home soil is now vital.
"That's the way it is in the Heineken," said the scrum-half. "If you don't win your home games you won't qualify. We want to qualify so we need to win those home games, starting on Sunday. It's a big game for us."
While Edinburgh had struggled in the early weeks of the RaboDirect PRO12 campaign, the victory over Munster gave them a massive confidence boost, and its effects have been seen in much-improved domestic performances that have helped to lever them up to eighth place in the PRO12 table.
Laidlaw said: "The Munster game was definitely the catalyst to push us on and we have had some good performances since then. I think we've now won four home games in a row, and we had not done that for a couple of seasons.
"It's very important for us to gain momentum. There was a big crowd here that day against Munster and we hope we get another big crowd on Sunday.
"It was the game where everything clicked. I was delighted for us as a playing group, and for the coaches' sake as well. Everybody had been working hard up to that point. It had been frustrating, but we were able to get that breakthrough. It was very pleasing."