Warren Gatland says Ireland made a mistake in asking for the roof to remain open for today's Six Nations clash at the Principality Stadium.
Whether or not the roof would be open or closed was a contested talking point in the build up to Wales' 25-7 trouncing of Ireland as they sealed the Grand Slam.
Joe Schmidt defied Gatland's wish to close the roof to the elements despite the storm warning hanging over Cardiff.
Under tournament rules, both teams must agree for the roof to be closed.
"I think Ireland made a mistake leaving the roof open," said Gatland said after today's win.
Ireland coach Schmidt added: "We usually play in those conditions really well, our set-piece is a real strength."
Gatland became the first coach to win three grand slams but insists the credit should go to the players.
He said: "I'm proud of the players. It's not about me it's about those players.
"We spoke about them playing for themselves and their families and this crowd.
"And being able to create a bit of history. You can never take that away from them now."
Read more here:
Gatland hailed the leadership qualities of Alun Wyn Jones.
"He's really matured as a player. He's done a great job leading this team this campaign.
"He's tough, he's resilient and he deserves all the accolades he gets because he's a fantastic person and a great player."
The New Zealander is confident if his side play to their potential they will be genuine World Cup contenders.
He said: "We know on our day that we're capable of beating good teams so we'll have a little bit of a break now and start building for the World Cup and planning and preparing for that.
"These boys train exceptionally hard, they'll run through a brick wall for you. They're a really tight group, really close to each other. Same with the coaching team as well and the whole management.
"We go there with a bit of luck, not pick up too many injuries and we've got a great chance of beating anybody."