New York's Frick Collection is revisiting an idea first mooted almost 100 years ago to create a permanent gallery dedicated to sculpture and the decorative arts.

This will be achieved by enclosing an underutilised section of the property on East 70th Street, the portico in the Fifth Avenue Garden, which is visible from inside the house but not open to the general public. Pending approval by the Landmarks Preservation Commission, the enclosure of the portico, set back from the original limestone columns and cornice, will create a new gallery within the existing footprint of the institution. It is anticipated that construction will begin in the autumn of this year, with an expected completion date of September 2011.

Margot Bogert, chair of the board of trustees of the Frick Collection, said: "With the creation of this new gallery, we will be able to present together significant examples of sculpture that are currently scattered throughout the institution in hallways and in galleries dominated by paintings. We hope to afford these objects the kind of sensitive display that Henry Clay Frick once dreamed they might have." The gallery will also accommodate cases for the display of porcelain.

A private foundation will fund the project and the Frick is raising endowment funds to support the costs of maintaining the new gallery in the future. New York-based Davis Brody Bond Aedas Architects and Planners (DBBA) will be undertaking the enclosure of the portico. Following a directive to incorporate the structure's existing features, the colonnade and exterior limestone wall will be retained as the gallery's main surfaces, while a sense of the outdoors will be kept intact through the use of glazing on the south side.

The existing stone materials will be retained, and the architectural details will draw upon those of the original mansion and Pope's enclosed Garden Court of 1935.