Mass Timber

Create a mass-timber-piece.

Mass timber inspires innovation.

Valued for its natural beauty, strength, and versatility, wood offers endless possibilities in architecture and design. Conveying warmth and sophistication, it can be used as a load-bearing structure and an interior finish material. Mass timber construction is capturing the imaginations of leading building and design professionals, who continue to evolve and advance its potential.

Skylab Sideyard street view exterior
Photo: Stephen Miller | Skylab
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Mass appeal.

Mass timber is a new category of wood product that can revolutionize how America builds. It is comprised of multiple solid wood panels nailed or glued together, which provide exceptional strength and stability. It’s a strong, low-carbon alternative to concrete and steel.  Mass timber building designs are pioneering better places for us to live and work, and new code changes were passed for the 2021 code cycle that allow mass timber buildings up to 18 stories tall.



CLT is a wood panel system that is rapidly gaining in popularity in the U.S. after being widely adopted in Europe. The material’s strength, dimensional stability, and rigidity allow it to be used in mid- and high-rise construction.

Cross laminated timber panel assembly illustration


Nailed it.

NLT is a century-old construction method that is undergoing a design renaissance. It can be found in historical buildings as well as in new projects, where its structural performance and design elegance come together to create inspiring spaces.

Mass timber NLT


Get dowel to business.

DLT is gaining traction for its ease of use with computer-controlled (CNC) machinery—such as lathes, routers, and mills—and its all-wood composition. DLT is similar to NLT but uses wood dowels to join boards instead of nails or screws.

Dowel laminated timber illustration



Glulam is a structural engineered wood product commonly used for beams and columns in residential and commercial applications. Glulam allows for long spans of exposed framing, as well as attention-grabbing curvatures.

Illustration of Glulam

It's all about connections.

Effective mass timber connections provide strength, stiffness, stability and ductility. Review these helpful tree-sources to learn more.

An illustration that show the different mass timber connections

How tall can you go?

In January 2019, the International Code Council (ICC) approved a set of proposals to allow tall wood buildings as part of the 2021 International Building Code (IBC).

Based on these proposals, the 2021 IBC will include three new construction types:

  • Type IV-A – Maximum 18 stories, with noncombustible protection on all mass timber elements.
  • Type IV-B – Maximum 12 stories, limited-area of exposed mass timber walls and ceilings allowed.
  • Type IV-C  – Maximum 9 stories, all mass timber permitted to be exposed (with a few exceptions e.g. shafts) and designed for a 2-hour fire resistance.

These new types are based on the existing Heavy Timber construction type (renamed Type IV-HT) but with specified hourly fire-resistance ratings for building elements and added levels of noncombustible protection. The code will include provisions for up to 18 stories of Type IV-A construction for Business and Residential Occupancies.

Illustration for different heights in wooden buildings
Construction trends.
Illustration of a Hybrid Building with wood floors
Hybrid Construction
Combining wood and concrete or steel in hybrid construction provides a cost-effective and sustainable solution for many occupancy types as well as improving building performance and design.
Read About Mass Timber Differentiators
An illustration of a Taller Wood building
Tall Wood
With recent changes in building codes on the horizon—and a quest to find more sustainable ways to build up—we are seeing a marked rise in the number of taller mass timber buildings popping up across North America.
Read About Tall Timber Trends
An illustration of a light-frame building with a wooden structure.
Infill and Overbuilds
Overbuilds are a technique to add additional stories on top of an existing building, maximizing development area per square foot. Infill refers to the development of vacant lots surrounded by other, existing buildings. Both building types are ways to address urban densification.
Read about Infills + Overbuilds
A portrait of Benton Johnson

Learn about hybrid construction in this podcast episode with Benton Johnson of SOM.

Fire Safety
Fire Station 76 exterior and engine

In terms of fire protection, building codes require all buildings to perform to the same level of safety regardless of materials. Wood buildings can be designed to meet rigorous standards for performance, which is why the International Building Code (IBC) allows the use of wood in a wide range of building types.

A portrait of Greg Kingsley
greg kingsley
president and ceo
Mass timber is ripe for innovation, invention, and collaboration with creative industry leaders.
Platte Fifteen CLT building street view
Platte Fifteen interior windows and CLT ceiling

Mass timber map.

Click on the location pins below to see mass timber projects across the country.

Webinars + Events

Get involved.

Check out upcoming wood webinars and events.
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