Supporters of the delay said they needed time to make much-needed repairs to the bill, which passed the Senate unanimously a week earlier.
"So much work has been invested in this bill, it would be a terrible shame that you would actually injure your constituents by moving forward with it as it is," said Rep. John Maher, R-Allegheny, who proposed the delay.
It passed 100-98, with Republican House Speaker Dennis O'Brien the only representative to cross party lines in voting against the measure.
Majority Leader Bill DeWeese, D-Greene, called the move a case of GOP obstructionism and "an obvious, obvious delaying tactic."
It was the latest pitfall for advocates of what has been a 13-month process of study, debate and revisions as the Legislature has considered how it might change the 1957 Right-to-Know Law, regarded by many as one of the nation's weakest.
And it was another frustration for Democratic leaders, who had to pull the plug on property tax reform legislation last week after a Republican-sponsored measure attracted dozens of Democratic votes to shift slots revenue to pay school taxes of lower income seniors only.
Critics of the open records bill said it would prevent real estate businesses from using government land records for commercial purposes, violate citizens' privacy and provide material for identity thieves. They said a provision that granted access to some 911 tapes and records was unclear and could expose victims and disclose criminal investigations.
The delay vote came after several amendments to address those issues failed because they required a two-thirds vote, a tall order in a chamber where the parties are separated by a single seat.
"I'm not going to say that the legislation is necessarily flawed, but I am going to say that I believe it's incomplete," said Rep. Matthew Baker, R-Bradford, who pushed for identity theft protections.
The bill would make all records open, beyond a list of exceptions, and would establish a central office in state government to mediate access disputes. Unlike current law, it would force government agencies to provide legal justification when they turn down a document request.
The changes also would greatly expand the universe of public records, granting new access to financial records of the General Assembly and state courts.
Democratic leaders argued that follow-up legislation could address all of the legitimate concerns.
"This has been bandied about, back and forth, seemingly for time immemorial," DeWeese said. He called it "the most significant piece of reform legislation in years and years, if not decades and decades."
Minority Leader Sam Smith, R-Jefferson, said Democrats control the voting calendar and can revisit the issue next week if they wish.
"We support an open-records bill," Smith said. "We think we could have made a few more changes today, to do it right. The fact that it would not become law, regardless of whether it hit the governor's desk this week or next week, until next year, speaks (for) itself."
The 48-page bill, sponsored by Senate Majority Leader Dominic Pileggi, R-Delaware, would shorten how long it takes to obtain a record and increase penalties for government officials who willingly violate the law.
It would cover community colleges and the four state-related universities: Penn State, Pitt, Lincoln and Temple. It would take effect in January.
It would bar access to autopsy records, but permit judges and local officials to release 911 tapes or records under certain circumstances.
The Pennsylvania Newspaper Association called it a substantial improvement over current law, but Common Cause of Pennsylvania said it was a weak product that did not go far enough.
