Only three Championship games survived the big freeze and Chris Coleman's men took full advantage to continue their recent improved form.
But they made heavy work of it and this game so easily could have ended in an away win had the Yorkshiremen taken a clutch of chances.
The visitors, who came to the Ricoh on a run of eight unbeaten games, had two clear early chances.
Skipper Steve Foster headed goalwards in the second minute and the ball bobbled dangerously around before Keiren Westwood managed to grab it at the last moment.
Then just two minutes later, another Foster header beat the Coventry keeper but hit the bar and went over.
If it was a scare for the home side, they didn't seem to heed it and it took them several more minutes before their finally found their feet.
Leon Best should have fired the home side in front when, after 17 minutes, he pounced on a mistake by keeper Luke Steele, but with the goal begging he fired high over the bar.
But then, almost from nowhere, they sprung into a two-goal lead.
Freddy Eastwood rounded off a fine move involving Stephen Wright and David Bell in the 24th minute to notch his sixth goal of the season.
Barnsley had not recovered before Sammy Clingan produced a scissor volley to rifle the ball in via a defender's head.
Coventry, however, allowed the visitors back into the game by starting the second half as slowly as they had the first.
Four minutes had passed before substitute Adam Hammill did well to make space and set up Jon Macken for a close-range finish.
Coventry rode their luck at times but made certain in the first minute of injury time when striker Clinton Morrison headed home.