The home side created enough chances to make a fist of the game but failed to put them away, an aspect of the match which infuriated Redpath.
"It was extremely disappointing to lose like that, we let ourselves down," said the Sale Sharks scrum-half.
"It's bit of a setback. Be under no illusions, Ireland are a very good side but our set piece was poor and we never really got a platform going.
"We created several chances when we were still in the game but we didn't take them. The harsh reality of rugby at this level is that if you don't take them you'll be punished."