The Denison Planning and Zoning Commission returned to recent discussions on preferred construction materials last week when it discussed future requirements for multi-family, non-residential and industrial construction. The discussions will ultimately lead to the drafting of a city ordinance amendment that is expected to be presented to the city council later this year.

The primary focus of this month’s discussion was on the percentage of exterior construction that must be masonry, and the building materials that are defined as masonry under the city’s building code.

“I am not going to just say masonry because depending on who you talk to it means five different things,” Denison Planning and Zoning Manager Steven Doss said. “So, we are just going to be specific on what is required.”

Throughout the discussion, cementitous composition fiberboard, finished concrete masonry unit, stone, brick, stucco and concrete panel were accepted as masonry. However Doss said different uses might have different regulations on which types of masonry are accepted.

Doss presented recommendations on proposed requirements for multi-family housing. He said the standards would be for 100 percent of the first floor to be stone brick or true stucco, with 30 percent of the remaining structure made of the same materials.

The remaining building can be made up of glass, fiberboard, exterior insulation and finishing system, more commonly known as EIFS, among other materials, Doss said.

Doss said investigations into building offset requirements lead to the recommendation that no additional requirements be made. Doss said the features of multi-family developments typically fulfill the need for interesting facades.

“Those requirements are really onerous to administer and when you have multi-family development you’re going to have deck and patios (among other features),” Doss said. “Staff’s feeling on that is we don’t need those requirements just based on how these products are built.”

City staff is still looking into amending and adding to a list of accepted add-on site features that can be included as amenities in these developments, and plans to present it at a future meeting.

However, the majority of the discussion was dedicated to industrial and non-residential developments. Doss noted that under current regulations, industrial districts allow for 100 percent metal construction, but this could lead to non-industrial buildings taking advantage of this.

“Under the ordinance right now, I can go in and do a 100 percent metal gas station as long as it is in the right zoning,” he said.

In response, the commission recommended building requirements be based not on the zoning but the intended use of the building.

With regard to metal structures, Doss also wanted to clarify city requirements regarding metal walls. Under the ordinance, metal walls must be profiled panels, thus eliminated corrugated metal as a material. While the ordinance has been interpreted as prohibiting R- and U-panel construction, Doss said he has gotten questions regarding this requirement.

“We are pretty clear that you can’t just put R-panel up and call it a day,” Doss said. “It has to be standing seam or an equivalent.”

The commission also recommended increasing the percent of industrial buildings that must be masonry to 30 percent of the front side. For other non-residential uses, the commission recommended maintaining the 75 percent requirement for masonry, Doss said.

Doss said he expects the discussions on building materials to continue over the next few months, with discussions on the city’s highway overlay districts to soon follow. The commission is expected to vote to accept the recommendations in September and forward them to the council for approval this fall.