The City Council is expected to decide Monday whether to allow the Violet Crown Charlottesville cinema to retain a tinted glass storefront that was installed without permission from the Board of Architectural Review.

“Darkly tinted mirrored glass is not an appropriate material for windows in new buildings within the historic districts,” reads one of the guidelines for the city’s architectural design control districts.

Soon after a remodeling of the former Regal Theater was completed last fall, a nearby property owner complained about the glass, which is opaque during the day but becomes more translucent as night falls.

The BAR had approved plans for the Violet Crown in March 2014 that specified clear glass would be used in keeping with city guidelines.

“When an unapproved material is installed, the applicant is notified of the zoning violation, and they are asked to make application for the substitute material after the fact,” wrote historic-preservation planner Mary Joy Scala in a staff report for the appeal.

“If the BAR fails to approve the new material, then the original approval stands,” she continued.

The original designer was local architect Mike Stoneking, but the cinema company hired an out-of-town firm to complete the design. TK Architects of St. Louis made several alterations, including switching the glass, without updating city staff or the BAR.

“The mistake was made in good faith, because TK was not aware of the clear glass requirement in the design guidelines, and Violet Crown was not aware of the change in the specification,” wrote attorney David H. Pettit of the firm Lenhart Pettit in a Dec. 29 letter to the City Council.

Violet Crown was able to get the BAR to retroactively approve several other changes between the original design and what was actually built, but the design panel stood firm on its insistence that tinted glass is not appropriate.

Pettit said the cost to replace the windows will be around $50,000 and that he wants the council to allow the tinted glass to remain.

“The extremely high usage of the Violet Crown over the pre-Christmas weekend period demonstrates that patrons are not deterred or confused by the existing glass,” Pettit wrote, adding that approximately 12,700 people bought tickets to see “Star Wars: The Force Awakens.”

Scala said it could set a precedent if the council sides with the Violet Crown.

“Failure to uphold the BAR decision would create uncertainty about guidelines that are very important to the character of a historic district [and] send a message to other applicants that they may disregard the BAR’s decisions,” she said.

In his letter to the council, Pettit argued that TK Architects believed that the originally approved glass would not be in compliance with state building codes.

“TK determined that the glass specified for the storefront did not meet the requirements of the Virginia Energy Conservation Code effective May 1, 2008,” he wrote.

Pettit said the existing windows are more energy-efficient, reducing the cinema’s impact on the environment. He also noted there are 17 mall facades that have tinted glass.

“Some buildings on the mall do have tinted glass, such as the Omni Hotel, which was built prior to adoption of the 1985 Downtown ADC District regulations,” Scala wrote. “Most energy-efficient glass has a slight tint. However, there are no examples of tinted glass on the mall that are as extremely dark as the Violet Crown theater.”

Scala also said the construction upgrade did not have to meet energy efficiency requirements added to the city’s building code in 2008 because it is not a new structure.

The council also is expected to hear a second appeal of another BAR decision on Monday. The owners of Preston Court Apartments want permission to remove two trees on their property. The BAR previously denied the request because the applicants had not submitted a landscaping plan.