Ashley Barnes and Chris Wood both celebrated the new contracts they signed during the week with first-half goals before a Roberto howler just before the hour put to bed any question marks over the outcome.
Story of the game
The game had not seen an effort of any great significance until Burnley won a pair of corners after 10 minutes. From the second, James Tarkowski nodded down to Barnes and he had the simple task of turning home to end a goal drought which stretched back to the draw at Wolves in August.
There was a further blow for West Ham with 20 minutes gone as captain Mark Noble was forced off with an ankle injury, Andriy Yarmolenko coming on in his place.
A Burnley second looked far more likely than an equaliser and the home crowd thought it had arrived when Wood got on the end of an excellent Dwight McNeil delivery, only for a VAR review to show that the striker was marginally offside.
The Turf Moor faithful were livid, though it seemed their fury was directed more at the increasingly unpopular technology itself than this particular decision.
But soon the atmosphere of frustration was lifted as Burnley capitalised on a poor West Ham error to double the lead shortly before the break. McNeil dispossessed Fabian Balbuena deep inside the visitors' half following Roberto's throw-out and he calmly slid it across for Wood, who fired home.
It was the same combination that yielded the disallowed goal, and this time it stood, continuing Wood's record of scoring in every meeting with the Hammers.
It took only nine second-half minutes for the game to be settled. Ashley Westwood swung in a corner from the left and Roberto, albeit surrounded by bodies, could only fumble the ball into his own net.
He faced a torrent of criticism from the West Ham supporters behind his goal but, shortly after Nick Pope preserved his clean sheet by denying Aaron Cresswell, he sought to redeem himself by making two good saves to deny Wood and another to push a Phil Bardsley strike behind.
The 'keeper was then fouled by Barnes in the scramble that followed another corner, meaning Ben Mee's strike was chalked off.
Wood, Jeff Hendrick and Jack Cork both went close to a fourth in the time that remained, while Yarmolenko saw a big half-volleyed chance for a consolation sail past the post.
The miserable afternoon for the increasingly sparse away section was completed when Manuel Lanzini concerningly had to be stretchered off in the final minutes.
Hammers in disarray
West Ham have endured a wretched run of form since they beat Manchester United in September, and this could be a nadir.
Something isn't right. The Hammers have plenty of quality at their disposal but they look blunt as an attacking force. Here they seemingly relied on Felipe Anderson or Pablo Fornals to produce a sudden moment of magic as they toiled, yet neither could make an impact.
Meanwhile, Sebastien Haller cut an isolated, even somewhat dejected, figure up front.
Manuel Pellegrini must revitalise this talented group of players in the immediate future, or he will face the axe.
Grim afternoon for Roberto
Inevitably, even though the visitors were found lacking in every department, fingers will pointed at deputising goalkeeper Roberto.
He was let-down by Balbuena in the build-up to the second but his blunder for the game-killing third was disastrous.
When his team next went forward, he took a lonely trudge up towards halfway as the away support made their feelings known. Every basic goalkeeping task he completed thereafter was met with ironic cheers.
He did his best to compensate, but there doesn't look to be a way back from here for the veteran Spaniard, who has failed to inspire any confidence during his run in the side. Third-choice David Martin will surely now be called upon next time out against Tottenham.
Either way, the return of Lukasz Fabianski in the New Year will be greeted with immense relief. It might just keep his team out of trouble.
Burnley's timely response
In his programme notes, Mee expressed his confidence that Burnley could end their three-game winless run owing to their strong record at home to mid-table rivals.
And so it proved, the Clarets comprehensively outperforming the opposition to claim three points which lift them back into the top half and, more broadly, indicate they won't be pulled into a relegation battle this season.
They move into the international break satisfied.
Man of the match
Barnes and Wood may have got the goals, but it was Dwight McNeil, the supplier of the second, who shone brightest. He tormented his markers throughout and delivered a series of swerving crosses which truly are a forward's dream.
Burnley have a hugely promising, and crucially consistent, player on their hands. They'll be keen to hold onto him as long as they can.