R47752 — Mass Timber: Overview and Issues for Congress

Mass timber is a class of engineered wood products made into structural pieces of much larger sizes and more diverse shapes than can be made with lumber alone. Mass timber is a substitute for conventional mineral building materials (e.g., steel, concrete) due to its size and physical properties. Mass timber also sequesters carbon and may result in less greenhouse gas (GHG) production during manufacturing than mineral materials. These characteristics have raised the possibility that mass timber could replace conventional materials in the commercial building sector and could generate associated co-benefits, such as reducing the sector’s carbon footprint—potentially on a large scale. Development of mass timber products has the potential to change the role of wood in the U.S. construction industry. Traditionally, most structures built with wood have been in the residential sector using light-frame wood construction: walls, roofs, and other structural assemblies made of nailed dimensional lumber and engineered wood, epitomized by familiar single-family housing construction. Buildings built with mass timber products can be larger and more complex than buildings made using light-frame wood construction. Because mass timber can be used to build tall wood buildings—defined as buildings that are six stories or more in height—mass timber can penetrate the commercial building sector. Mass timber and tall wood buildings may have some disadvantages over conventional construction methods or may face barriers to adoption. Because mass timber is an emerging technology with minimal market share, researchers identify high costs, unfamiliarity within the construction community, and unresolved questions about performance as potential disadvantages compared with conventional construction. In some cases, it is unclear whether these issues are intrinsic to mass timber itself or would change if mass timber were more widely used. Recent changes to model building codes may reduce barriers to increased construction of tall wood buildings. However, in general, mass timber and tall wood buildings comprise a small portion of the U.S. building economy. As of March 2023, 1,753 mass timber projects had been constructed or were in design in the United States; for context, 5.9 million commercial buildings were constructed in 2019 alone. Mass timber’s potential to replace mineral materials has generated interest from those seeking to reduce the building sector’s environmental impacts. Mass timber products may improve on the GHG-related characteristics of mineral materials in two ways: mass timber sequesters carbon, and mass timber generates relatively lower GHG emissions in production compared with mineral materials. Proponents of mass timber also have forecast a number of possible “upstream” benefits of mass timber production and manufacturing, particularly if mass timber construction were adopted on a broad scale; these benefits stem from mass timber’s potential to grow wood’s role in the construction industry and, in turn, potentially drive increased demand for timber. Mass timber has therefore become part of a broader conversation about the role of timber markets in driving the extent, composition, health, and management of forests. The federal government funds research and provides financial and technical assistance to facilitate wood product innovation, including development and deployment of mass timber and tall wood buildings. This is generally (but not exclusively) done through the Forest Service’s (FS) State and Private Forestry (SPF) and Research and Development (R&D) mission areas, although some authorities also relate to management of FS and Bureau of Land Management (BLM) federal forests. Notable programs include the Wood Innovations Grants Program in the SPF mission area and the Forest Product Laboratory in the R&D mission area; however, numerous other programs and authorities may apply. Should Congress wish to further incentivize mass timber research, development, and use, it may consider several options, including expanding existing assistance and research programs within the FS; applying materials preferences to federally owned or funded building and infrastructure projects; and offering incentives as part of applicable federal timber harvesting projects.

Curated by CRS — every bill listed in this report's relatedMaterials. Edge type cited_in_report, gold confidence.

• HR 5044 — Timber Innovation for Building Rural Communities Act · 118th Cong
• S 2991 — America’s Revegetation and Carbon Sequestration Act of 2024 · 118th Cong
• S 2662 — Timber Innovation for Building Rural Communities Act · 118th Cong