Goals either side of half time by Neil Mellor ensured the Owls returned to winning ways at Hillsborough against Colchester.
The recalled striker was too sharp for the U's as Wednesday turned in their best home performance since the demolition of Bristol Rovers before Christmas - their last S6 success.
Steven Gillespie scored a last-gasp goal for Colchester to halve the arrears but it was too little too late for the U's.
Boss Gary Megson called for a steely display and got exactly that with a victory that gives the Owls valuable breathing space at the wrong end of the League 1 table.
Both sides made lively starts, with Colchester shading the early possession but the Wednesday defence was resolute, charging down the shooting threat of the visitors.
Moving forward, the Owls were cohesive and confident, with James O'Connor asking the first question with a snapshot that rolled just the wrong side of the post.
But Colchester then spurned a gilt-edged chance when David Mooney volleyed wide from 12 yards after gaining a clear sight on goal.
Richard O'Donnell was forced into a low diving save from Ashley Vincent's drilled shot moments later, before Ben Williams had to be alert at the other end to deny Jermaine Johnson.
And from the resulting corner on 24 minutes, the Owls took the lead. The ball was cleared to Jon Otsemobor, who fired back into the box and Mellor was on hand to clip calmly over Williams.
Mellor was at the centre of the action again on the half-hour mark, this time tumbling in the area under a challenge by Nathan Clarke but the referee waved away Wednesday appeals for a penalty.
The Owls stayed in the box seat as half time approached and Gary Madine almost doubled the advantage, coming within a whisker of getting something on Mellor's curling cross.
Wednesday came out for the second half in similar mood and promptly extended their lead on 51 minutes.
The source was the same too - Otsemobor sending in a fizzing cross that Mellor finished expertly with a powerful header that gave Williams no chance.
The Owls were in the mood and Tommy Miller pounded a fierce shot that whistled narrowly over the bar.
Bur Colchester were far from out of the game as was evidenced with two chances in as many minutes.
First, O'Donnell came to the rescue with a brave stop to keep out Vincent, before Gary Teale cleared a Matt Heath header off the line.
That was as good as it got, though, for the Essex side as Wednesday threatened to turn the screw.
Twice Mellor might have had a hat-trick as the hitman had another claim for penalty turned down before his skewed shot at the far post was deflected wide at the last.
But Mellor had already done the damage and despite Gillespie's consolation on 89 minutes - the midfielder thumping home from close range - the Owls can head into Tuesday's game against fellow strugglers Tranmere with a much-needed boost.
Owls: O'Donnell, Otsemobor, R Johnson, Batth, Buxton, Teale (Coke 85), Miller, O'Connor, J Johnson (Sedgwick 79), Madine, Mellor
Unused substitutes: Nicholls, D Jones, O'Brien, Potter, C Morrison
Colchester: Williams, Clarke, Vincent, Izzet (O'Toole 75), Bond, Perkins (James 61), Gillespie, Mooney (Odejayi 67), Wilson, Coker, Heath
Unused substitutes: Cousins, Henderson, Wordsworth, Smith