The Terriers held out until half-time after seeing defender Murray Wallace dismissed on 17 minutes but conceded three times in the opening five minutes of the second period, with Bradley Johnson scoring twice and substitute Nathan Redmond also hitting the target.
It was just what the Canaries needed after winning only one of their previous seven fixtures at Carrow Road – and Cameron Jerome and substitute Lewis Grabban later provided the icing on the cake with a further goals.
Looking to build on only their second win in 11 matches at Wigan last week, Norwich made a bright start and Johnson almost got on the end of Gary Hooper’s low cross in the very first minute.
Johnson then fired narrowly wide from just outside the area as a Huddersfield side featuring former home favourite Grant Holt struggled to get a foothold in the game.
But they nearly took the lead against the run of play on 12 minutes when keeper John Ruddy needed to make a good block to foil Nahki Wells before the striker’s follow-up effort came back off the crossbar.
The Terriers suffered a setback of their own making seven minutes later when they were reduced to 10 men following the dismissal of defender Wallace for a professional foul. A high punt forward from Hooper should have been dealt with by Mark Hudson but the skipper mis-controlled and Jerome was in on goal before being taken out by Wallace, who was rightly shown the red card by referee Mark Brown.
Jerome’s free-kick came to nothing but the Canaries were now well and truly on the front foot and Hooper might have done better with a header that was straight at keeper Alex Smithies. The same certainly applied to Jerome, who missed with a free-header from a corner at the back post, and, for a second time, Hooper, who got the ball stuck under his feet with just the keeper to beat moments later.
Huddersfield defended well to hold out until half-time, but it all went wrong for them in the first five minutes of the second period.
With just 46 seconds on the clock a neat move down the right ended with Hooper skilfully pulling the ball back for Johnson to convert from close range.
From virtually the next attack Martin Olsson crossed for half-time substitute Redmond to head home only his second Norwich goal and the game was over as a contest in the 50th minute when Johnson scored his second.
This time there was a touch of good fortune about the goal, with a block from Jonny Howson’s shot falling perfectly for his midfield colleague to tuck the ball home.
Smithies made a good save to deny Redmond as Norwich pushed for more goals, before a swift raid saw Johnson, who was looking for his hat-trick, fire just over.
It was one-way traffic by now and Huddersfield-born Jerome made it 4-0 on 69 minutes when he headed home from close range after Hooper had nodded Olsson’s cross into his path.
Norwich still were not finished and added a fifth on 77 minutes, substitute Grabban making his first touch count after being put through by fellow substitute Wes Hoolahan.