Type III-B Application of LP® FlameBlock® Fire-Rated OSB Sheathing Provides Cost-Saving Solution for Denver Framing Company


Denver-based RT Framing is a framing and drywall company specializing in multifamily and commercial construction projects. In July 2015, Russell Beilby, Vice President at RT Framing, began work on Belleview Block B, a multifamily project in the Belleview Station neighborhood in Denver.

In order to meet local fire codes, Beilby used LP® FlameBlock® Fire-Rated OSB Sheathing as a code-compliant component of a two-hour fire-rated exterior wall assembly throughout the 330-unit Type III-B building. He found the product provided a cost-saving solution, as he was able to save on labor costs and equipment rentals by only using one layer of LP FlameBlock sheathing compared to two layers of gypsum.


Beilby set out to frame the Type III-B structure as efficiently and cost-effectively as possible. Since the building was seven stories tall, he wanted to avoid having to rent additional equipment that would typically be needed to install a second layer of gypsum on the higher stories.


A sales representative at Direct Lumber and Door of Colorado introduced Beilby to LP FlameBlock sheathing. After learning about the product benefits, he opted to use it on the Belleview project.

LP FlameBlock Fire-Rated OSB Sheathing carries a Class A and 30-minute flame spread rating due to its proprietary non-combustible, fiberglass-reinforced Pyrotite® treatment. Using LP FlameBlock sheathing in fire-rated wall assemblies reduces dead load and wall thickness versus common alternative assemblies.

As a result of his decision to use LP FlameBlock sheathing, Beilby achieved a simpler and more efficient installation process, particularly on the higher floors of the structure.

"I decided to use LP FlameBlock not just for the labor-saving aspect, but for the means and methods," said Beilby. "Putting on one sheet is simple because you can lean through the studs. It's the second sheet that causes difficulty because you have to rent equipment like cherry pickers and boom lifts, which can run about 6 000 $ a month. I chose LP FlameBlock because there would be no need for a second layer of product."

Since the Belleview Block B’s U349 wall assembly did not require the second layer, Beilby had no need for additional equipment.


By using LP FlameBlock sheathing on the Type III-B structure, Beilby ended up saving RT Framing thousands of dollars in additional equipment costs that would have been required had he used two layers of gypsum.

He also ended up saving in labor costs. "I pay [my framers] about 8 $ for every sheet that is installed. I was able to drastically cut down on installment costs by using one layer of LP FlameBlock instead of the two layers of gypsum."

When asked if he'd recommend LP FlameBlock sheathing to other framers, Beilby says, "For Type III construction? Absolutely."

The Belleview Block B apartments are set to be finished in December 2016 and are the second phase of the larger Belleview Station development, a new master-planned development featuring pedestrian-oriented streets, mix-use buildings, and convenient access to the transit system.