City Council wrestled with three major changes to the city business landscape yesterday, with mixed results.

In its final meeting of the year, Council approved zoning to construct Philadelphia's tallest building; heard Councilman Darrell L. Clarke's proposal to ease the plumbing code and reduce building costs; and continued to question Verizon Communications' proposed franchise agreement to compete in the Comcast-dominated local cable television market.

Council approved, 16-0, a law that will allow the Planning Commission to consider the 1,501-foot-tall American Commerce Center on Arch Street between 18th and 19th Streets. Developer Hill International does not yet have an anchor tenant for its $1.1 billion office building, hotel and retail complex. It must submit a plan and get approval from both the commission and Council.

Before that vote, Clarke introduced a bill to accomplish what developers have demanded for years - elimination of a requirement that all commercial construction, and many residential buildings, use cast-iron pipes instead of more commonly used PVC.

Developers say the use of iron pipes - not required anywhere else in the state - easily doubles plumbing costs for materials, labor and repairs.

"I think it's a great start," said John Westrum, chief executive officer of Westrum Development Co. in Fort Washington and one of the harshest critics of the plumbing code. "The builders in the region welcome the ability to use 20th-century technology in the 21st century."

"It's a great step forward in bringing Philadelphia in line with the rest of the country in our code requirements," said Bart Blatstein, president and CEO of Tower Investments in Northern Liberties.

Clarke said he hoped for support from the plumbers union, with whom he negotiated the bill.

John I. Kane, business manager for Plumbers Union Local 690, said he would oppose any inclusion in the bill of the international plumbing code, which he described as a "watered-down" version of Philadelphia's.

Clarke said he would remove a reference to the international code in the legislation without changing its effect.

Council's meeting was delayed nearly two hours by a frenzy of activity around a scheduled 9 a.m. committee meeting on Verizon's proposed franchise agreement to bring its FiOS network to Philadelphia.

That delay included packs of lobbyists coming and going from Council chambers and a closed-door meeting of the Committee on Public Property and Public Works that appeared to violate the state open-meetings law.

Comcast Corp. has a virtual cable monopoly in Philadelphia. Verizon negotiated a contract with the Nutter administration that featured a $700 million investment and a seven-year rollout. Verizon came to Council on Nov. 13 and wanted ratification of the deal by year's end. But Council members wanted Verizon to install its system sooner, at least in some neighborhoods.

"I don't need a big percentage of this, but I don't need to be embarrassed when I go to a whole lot of Verizon phone customers and tell them they've been shut out," said Councilman Brian J. O'Neill, whose district includes all of the Far Northeast.

Verizon obliged, adding parts of O'Neill's district to the first phase. Council members have complained of being rushed to approve the deal, and O'Neill said Council's delay had already produced a more equitable plan.

Verizon also faces a push from Wilco Electronic Systems Inc. - the only other cable-television provider in town - for a stake in the deal. Wilco provides cable service to all Philadelphia Housing Authority customers.

Clarke, chairman of the Committee on Public Property and Public Utilities, recessed the hearing until Jan. 22. Verizon spokesman Harry J. Mitchell said the company had expected the approval process to run into January.

"We feel we've answered the questions that were raised at the first hearing," Mitchell said.

Clarke met before the meeting behind close doors with committee members Frank DiCicco, William K. Greenlee, Joan L. Krajewski, Donna Reed Miller and Frank Rizzo in Greenlee's office.

Council was criticized during recent budget discussions for meeting with Mayor Nutter in closed-door briefings. Clarke said the committee yesterday was not discussing the Verizon deal but was seeking Council lawyer Rick Auerbach to ask about its ability to recess the hearing.

"I think talking about the procedure of a committee process is not within the Sunshine Act," Clarke said. "I don't know why it would be."

Clarke said he did not ask for a legal opinion.

Melissa Melewsky, counsel to the Pennsylvania Newspaper Association, offered her own opinion.

"To the extent that the agency was deliberating policies that govern the conduct of public meetings, I think that discussion should have occurred during a public meeting," Melewsky said. "If the solicitor was explaining agency policy regarding the hearing process and answering questions about it, I think the public was entitled to hear that discussion as well."

DiCicco said members thought they were within their right because they did not have the nine members required for a quorum. It wasn't until afterward, DiCicco said, that he realized only five members were required to have a quorum of the seven-member committee.

Contact staff writer Jeff Shields at 215-854-4565 or jshields@phillynews.com.