Multi-Housing News, February 17, 2025
US MgO Company will soon be the first to manufacture these panels domestically.
An increasingly popular but not yet well-known type of cement sheathing panel enables multifamily developers to lower insurance costs and build projects faster. Made from magnesium, the world’s most abundant mineral, magnesium oxide cement panels are naturally fire resistive, structurally strong and resistant to moisture, mold and deterioration from weather conditions during and after construction.
A new manufacturer based in Wilmington, N.C., US MgO Company, with deep experience incorporating structural insulated panels in multifamily projects across the U.S. will soon be the first to manufacture the panels domestically.
“Even though most multifamily developers have never heard of MgO panels, they can easily value their benefits by drawing simple and cost-effective comparisons to the wood and gypsum-based panels they use in projects every day,” said Ryan Miller, general manager of US MgO. “In addition to meeting the needs of traditional panels, MgO panels can lower insurance costs by incorporating cost-effective fire-rated wall assemblies with NFPA 285 approved assemblies when required.”
Unlike wood panels, MgO panels will not deteriorate, warp, swell or delaminate in normal or harsh weather conditions. According to US MgO, Innovation MgO Wall Panels can be left fully exposed for up to six months during construction and still receive a 10-year limited product warranty. Naturally fire resistive, MgO panels outperform fire retardant treated plywood panels when fire ratings are needed and can be used in place of OSB in floor and subfloor systems, even when left exposed to the elements during construction.
Unlike interior and exterior gypsum panels, which are not structural, structural MgO panels enable direct attachment of many light and mid weight cladding systems on the exterior and can be installed in all weather conditions, including for interior walls, saving material and labor costs while speeding up projects.
When quality framing allows for it, rigid MgO panels replace wet-laid gypsum systems that introduce unwanted moisture into the subfloor system and require costly time to cure. Instead, MgO panels are attached directly to trusses, allowing work on the floor above to begin without delays. These benefits oftentimes make up for the slightly higher price of MgO panels.
“Multifamily developers looking to lower their insurance costs and speed their construction projects can start by specifying MgO panels in walls, floors and subfloors where fire ratings are needed, structural strength is desired, or to simply protect against weather or delays during construction,” Miller said.
Common starting points, he noted, include breezeways, hallways, stairwells and other walls that can benefit from added impact and moisture protection.
“Even painted, these MgO panels are tough and durable,” Miller noted. “You can run a cart or a hammer into them and they won’t be damaged. They offer long-term value for owners and operators.”
Full exterior load bearing fire-rated assemblies with NFPA 285 approvals are available. Common assemblies incorporate polyiso insulation attached to wood or metal studs with a layer of 1/2″ MgO as the sheathing and a wide selection of water-resistive barrier products that are widely used by developers already.
Visit www.USMgO.co for these and other technical resources.
About Innovation MgO
The Innovation MgO series of sheathing panels includes 1/4” Flex Panels for SIP and SIS products and interior walls, 1/2” Wall Panels for exterior load-bearing fire-rated walls and interior fire-rated walls, 1/2” Floor Panels for flooring underlayment, and 3/4” Subfloor Panels for use in structural subfloors. Innovation MgO 1/2” Wall Panels recently received their first Evaluation Services Report (ESR) ESR-5418 from ICC-ES applicable to Acceptance Criteria (AC) 386, the industry-recognized standard for fiber-reinforced magnesium oxide panels. Consult published Innovation MgO assembly requirements and local building codes for fire-rated design requirements.
About US MgO Company
US MgO is a leading supplier and manufacturer of high-quality magnesium oxide (MgO) cement sheathing panels catering to the commercial, multifamily, and single-family construction markets in North America. US MgO was established by a team of accomplished building products industry veterans and partners that boast decades of experience in the development, research, and manufacturing of MgO sheathing panels and innovative building products. In January of 2025, US MgO commissioned the first U.S. facility to manufacture domestic MgO panels for use in walls, floors, and subfloors. A second manufacturing plant will break ground soon after.