The home side went ahead with a headed goal from centre-back Andre Bikey from a free kick from Stephen Hunt.
Then, having clawed their way back into the game courtesy of Mario Zarate's first Premier League goal, Blues were again their own worse enemies when they conceded again from a right wing free kick, Bikey again the scorer for the hosts.
"It's very disappointing," said the Blues boss after the 2-1 defeat at The Madejski Stadium.
"We've lost to two similar goals from set pieces with the same player scoring both goals.
"People are saying that we are always going to concede goals but it's ironic that our goal difference amongst the lower side's is one of the better ones. However, goals from set-pieces have cost us dearly in recent games.
" It's looking like we're going to have to score two or three goals to win a game
"Having said that I thought we deserved all three points today.
"It's important we pick up some wins because it's becoming so tight. But we need to keep everyone fit and stop shipping goals."
McLeish also highlighted the fact that Blues had missed in-form striker James McFadden who was not in the line-up against Reading having undergone knee surgery.
"He's been in excellent form of late and definately added something to the side since joining us,"McLeish added.
"He'll maybe miss three games but it's vital we get him back for the final run-in."