Case Studies

Washington, D.C.

LP® FlameBlock® Sheathing Made Construction Faster and Easier at Trellis House

Project Summary


Founded more than 40 years ago, Atlanta-based Niles Bolton Associates (NBA) has designed projects in 49 states. The company designed Trellis House, a mixed-use, market-rate rental community near Howard University in Washington, D.C. After a July 2016 construction start, the project was completed just two years later in July 2018. While it is home to many Howard University students, Trellis House was not exclusively or purposefully built for them. It has 50 units dedicated to Howard University faculty and staff. There are also about 10,000 square feet of retail space in the development. Trellis House has five floors of Type IIIA residential construction over two levels of Type IA cast-in-place concrete that includes residential units in addition to parking, building amenities, and some retail. The developer’s theme for Trellis House was to “provide someone a great place to live, work and grow.” The development is LEED Platinum certified, with green roofs and a hydroponic rooftop garden. It was named a 2019 finalist in the U.S. Green Building Council LEED Homes Awards Project of the Year.



“The exterior walls near the property line needed to be 2-hour fire-rated on both sides, so we chose UL wall assembly V337* that incorporates LP FlameBlock Fire- Rated Sheathing,” says Kevin Cabitt, NBA’s project architect on the Trellis House build. The UL assembly V337 provides a 2-hour rating for fire exposure on either side of the wall. This is helpful when building close to the property line, where a 2-hour fire rating is required by building codes. In addition to meeting the code requirements for flame spread, LP FlameBlock assemblies help reduce the overall wall thickness compared to common alternatives. The LP FlameBlock panels have an Exposure 1 rating, which means that they can withstand exposure to moisture during normal construction delays. The panels also provide an excellent substrate for securely fastening exterior-facing cladding.

LP FlameBlock Trellis House Case Study

"LP reps are very proactive about giving us the resources we need to do a better job." - Steven Gresham, Principal, Niles Bolton Associates



Says Cabitt, “During construction, the windows were installed on one façade before the code officials requested the wall to be 2-hour rated for exposure to fire on both sides of the wall. After a quick examination of assemblies utilizing LP FlameBlock Fire-Rated Sheathing, we determined our needs were satisfied by V337. Some wall assemblies would have required taking out the windows to do that, but not the V337 assembly. That saved a lot of time and money on the project.” CBG contractors didn’t attempt to swap out any of the materials specified for the Trellis House wall assemblies. “One of the reasons we like working with CBG is that they recognize that it’s difficult to change anything that has to do with the fire safety of the building,” says NBA principal Steve Gresham. “We didn’t have to convince them that the LP solution was the way to go.” Gresham continues, “LP reps are very proactive about giving us the resources we need to do a better job and meet rigorous fire codes. For example, they keep us informed about newer assemblies that make it even easier to get approvals from code officials.”

Awards & Recognition for Trellis House:

  • Finalist in the U.S. Green Building Council LEED Homes Awards Project of the Year
  • 2019 "Best Mixed Used Project (over $50 million) by the Associated Builders and Contractors of Metro Washington and Associated Builders and Contractors of Virginia


*Formerly W408 Extended, now tested with UL designation