For most of the 20th century, wood was largely a material for single-family homes and low-rise construction. Steel and concrete dominated anything taller or larger. That assumption is changing rapidly. Mass timber — engineered wood products like cross-laminated timber (CLT) and glue-laminated timber (glulam) that can be manufactured to structural specifications suitable for large commercial, institutional, and multi-story buildings — has grown at roughly 20% per year since its U.S. introduction in 2015, according to reporting by Trellis and industry data from WoodWorks. Today, more than 2,500 mass timber projects are built or in progress across the United States — and the pipeline continues to grow.

The shift is visible in the buildings going up: Google offices, Microsoft campuses, Under Armour's Baltimore headquarters, and a wave of university buildings, K-12 schools, and mixed-use developments from the Pacific Northwest to the Southeast. The category is no longer an architectural novelty. It is becoming a legitimate mainstream structural option — and the construction industry's understanding of how to price, detail, and build with it is deepening with every project delivered.

What Mass Timber Is — and Why It Is Growing

Mass timber refers to structural wood products engineered for dimensional stability and load-bearing performance at scales comparable to steel or concrete. The most common varieties are cross-laminated timber — in which lumber boards are stacked in alternating orientations and bonded under pressure, creating large panels with exceptional two-directional strength — and glue-laminated timber, or glulam, in which boards are stacked in parallel and bonded to create beams and columns of virtually any size.

The category also includes nail-laminated timber (NLT), dowel-laminated timber (DLT), and structural composite lumber. The diversity of products allows mass timber to serve as floors, walls, roofs, columns, and beams — either as a complete structural system or in hybrid configurations alongside steel or concrete for specific elements such as stairs, elevator cores, and lateral bracing.

The drivers of growth are multiple and reinforcing. Building code changes have been fundamental: the International Building Code has progressively expanded permitted mass timber heights, and as of 2021, the IBC allows mass timber buildings up to 18 stories in height under specific fire-resistance conditions — a change that opened a vast range of commercial and residential project types to the material for the first time. Fire performance in mass timber is now widely understood to be comparable to that of steel and concrete for most building types, owing to the way the outer char layer on heavy timber insulates the structural core during a fire.

Sustainability and embodied carbon are increasingly important drivers, particularly for institutional and corporate clients with climate commitments. Buildings account for roughly 37% of global greenhouse gas emissions, according to the United Nations Environment Programme, and cement and steel production contributes approximately 11% of global emissions. Mass timber sequesters carbon from the atmosphere in the wood itself — each cubic meter of timber stores approximately one tonne of CO₂ — and replaces materials with much higher embodied carbon. Under Armour's new Baltimore building, designed by Gensler, saved over 69% on embodied carbon by substituting mass timber for steel and concrete, according to Trellis.

Speed and schedule are also compelling. Mass timber panels are manufactured off-site to precise tolerances, arrive ready for installation, and require fewer on-site workers than equivalent steel or concrete construction. Industry practitioners cite 20% to 30% shorter schedule durations compared to conventional structural systems for comparable project types — an advantage that translates directly into earlier occupancy and earlier revenue generation for developers.

Supply Chain: Growing Domestic Production, but Still Reliant on Imports

The U.S. mass timber manufacturing base has expanded significantly. Over the past decade, 13 new production plants have opened domestically, bringing total U.S. and Canadian CLT production from 158,000 cubic meters in 2019 to 393,000 cubic meters in 2023 — a 149% increase in four years, according to the 2024 International Mass Timber Report. The number of mass timber buildings constructed annually in the U.S. and Canada rose from 151 to 279 over the same period. Manufacturers include Timberlab, Mercer Mass Timber, and several regional producers, with major facilities on the Pacific Coast and in the Southeast to serve the country's two largest mass timber markets.

Despite domestic expansion, U.S. builders still rely on imports from Europe — particularly from Austria, Germany, and the Nordic countries — where the mass timber industry has been mature for two to three decades longer than in North America. European producers benefit from larger production volumes, more automated manufacturing lines, and decades of technical refinement. As domestic U.S. production capacity grows and local sourcing becomes more practical, the cost premium for mass timber is expected to compress further.

The Modular Building Institute's 2024 market analysis — which encompasses mass timber alongside other offsite manufacturing methods — notes that U.S. offsite construction broadly is growing at a compound annual rate of 4.5%, driven by labor shortages, schedule pressures, and demand for consistent quality. Mass timber's growth rate significantly exceeds that average, reflecting the sector-specific tailwinds of code changes, sustainability commitments, and corporate real estate demand.

The Cost Question: Premium Upfront, Competitive Over Time

Mass timber's most frequently cited barrier is first cost. JJ Rivers, a principal at Gensler, estimates that mass timber typically carries a 20% to 30% premium on structural material costs compared to conventional steel or concrete framing. That premium is real, though it varies by project type, region, and the degree to which a design is optimized for mass timber from the outset rather than adapted from a conventional framing scheme.

The full lifecycle picture is more nuanced. Mass timber projects often require less foundation depth and smaller foundation footprints due to lower structural dead loads, generating savings on site and foundation work. On-site labor costs are lower due to fewer workers, simplified connections, and faster erection. And the intangible value is increasingly documentable: research from Virginia Tech and others has found that occupants in mass timber buildings report improved well-being, reduced stress, and higher workplace satisfaction — factors that translate into real estate premiums in the commercial market.

The USDA Forest Service's Wood Innovations Grant Program has provided targeted support for mass timber project development, and several states have passed legislation incentivizing or requiring mass timber consideration in public construction. The Biden administration in 2023 pledged to establish a Mass Timber Hub in Portland, Oregon, as part of a broader advanced materials initiative, though the status of that program has been uncertain under the current administration.

What the Next Several Years Hold

The mass timber pipeline is robust. In 2026, notable projects include a wave of university buildings, multifamily residential towers, and corporate campuses across the country. The University of Toronto's Academic Wood Tower — projected to be the tallest academic wood building in the world — is nearing completion. Softwood Lumber Board-funded mass timber accelerator programs in Boston, New York City, and Atlanta have catalyzed project pipelines that will continue producing groundbreakings through 2026 and 2027.

For construction professionals, mass timber presents both an opportunity and a learning curve. Detailing, connection design, fire protection, moisture management, and procurement lead times all differ meaningfully from conventional structural systems. The firms that have invested in mass timber expertise — specialized detailers, experienced erectors, and contractors who understand prefabrication coordination — are winning the work as the category scales. Those who have not are finding that the complexity of mass timber is real, even as the industry's knowledge base grows rapidly with each completed project.

The 20% annual growth rate in mass timber projects is not a ceiling. It reflects where the market is in a maturation curve that, if it follows the pattern of European mass timber markets, still has substantial runway ahead. Over 2,500 U.S. projects into its expansion, mass timber is no longer emerging. It has arrived.

Sources

Trellis — Mass Timber Usage Rises in U.S., European Building Construction (October 2025)
Wood Central — Mass Timber Could Surge 25-Fold (March 2024)
WoodWorks / Wood Products Council — Mass Timber+ 2025 Conference Summary (November 2025)
Softwood Lumber Board — Mass Timber Accelerator Programs in Boston, NYC, and Atlanta
Modular Building Institute — U.S. Modular Construction Market Analysis (2024)
Coherent Market Insights — Green Construction Market Analysis (2026)