In a replay of a controversial 2009 decision, the Planning and Zoning Commission on Thursday unanimously approved a text amendment that paves the way for redevelopment of the vacant downtown landmark, National Hall.

The package of zoning changes was submitted in August to the Planning and Zoning Commission by Greenfield Partners, a commercial real estate firm that is seeking to relocate its corporate headquarters from South Norwalk to National Hall, which sits on the west bank of the Saugatuck River.

To accommodate this use, Greenfield's Text Amendment 638 removes a ban on office use on the first floor of National Hall. The amendment also eliminates a cap that limited office use to 10 percent of the total gross floor area of all buildings in the Historic Design District where National Hall is located.

"I really hope that all of the times that I have seen applications for this zone, that something happens and it's built," said commissioner David Press.

P&Z Commission Chairman Ron Corwin concurred.

"I think Mr. Press voices a sentiment that is widely shared," he said.

The commissioners' comments were an apparent reference to a contentious public debate about the use of National Hall that unfolded almost two years ago.

In December 2009, the P&Z approved a similar text amendment for the Historic Design District that was also proposed by Greenfield. At the time, the commercial real estate firm was a prospective buyer looking to acquire the approximately 20,000-square-foot property from then-owner, Antares Investment Partners.

A pair of west bank merchants subsequently appealed the decision to the Representative Town Meeting. In January 2010, the RTM upheld the petition, which ruled out Greenfield's plans for offices on the site.

Two months later, the building's then-occupant, the Inn at National Hall, closed. The boutique hotel had operated at the site since 1993. In April 2010, a Greenfield affiliate acquired the mortgage on the property and later foreclosed on it. Greenfield now owns the landmark, which has languished without occupants since the hotel's closing.

To move forward with redevelopment, Greenfield must next submit a site plan and special permit application to the P&Z. The commercial real estate firm intends to present this formal proposal "in the very near future," according to its land-use counsel, Bill Fitzpatrick.

All of National Hall would be occupied by Greenfield's new headquarters. Greenfield's preliminary plans for the National Hall complex also envision a three-story addition to the rear of an adjoining building at 8 Post Road West that would have office space on the upper floors and retail or restaurant use on the first floor.

The P&Z's approval of the text amendment will also likely increase the probability of attracting new restaurants to the west bank. Greenfield has secured letters of intent to open three new restaurants in other buildings it owns on the west bank. Those letters were contingent upon approval of Text Amendment 638, according to Fitzpatrick.

Among the list of possible new restaurants for the area are eateries proposed by the Fairfield Middle Eastern restaurant, Safita, and Bar Taco, a Mexican restaurant chain.