Sidewalk Labs and Collaborators Design a 35-Story Timber Building

The recently revealed Proto-Model-X building would reach new heights for timber.

1 minute read

January 28, 2020, 9:00 AM PST

By James Brasuell @CasualBrasuell


Cara Eckholm shares the newly revealed details of a net-zero, timber building that would reach 35 stories if built.

The building, referred to as Proto-Model-X, or PMX, is currently in the "proto-model" stage. A large collection of design and engineering firms worked with Sidewalk Labs to create the design. Eckholm credits Aercoustics, Aspect Structural Engineers, Atelier Ten, CadMakers, Gensler, Integral, JE Dunn Construction, Michael Green Architecture, RDH, Sweco, and Vortex Fire for the current status of the design. 

As Eckholm notes in the article, 35 stories has yet to be achieved by a timber building. The proto-model stands as a "digital proof-of-concept" for the idea:

The concept is borrowed from manufacturing, where it’s common to design one perfect “widget” before producing them en masse in a factory. With PMX, our “widget” is a 3D building model rendered in Autodesk’s Revit, a popular building design software, and hosted in BIM 360, a cloud-based tool that stores technical information about the building.

Eckholm's article serves to introduce two explorations of the concept, each with their own article (Exploration 1 and Exploration 2) on the Sidewalk Labs website.

Friday, January 24, 2020 in Sidewalk Talk

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Cover CM Credits, Earn Certificates, Push Your Career Forward

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

June 4, 2025 - Diana Ionescu

Metrorail train pulling into newly opened subterranean station in Washington, D.C. with crowd on platform taking photos.

Congressman Proposes Bill to Rename DC Metro “Trump Train”

The Make Autorail Great Again Act would withhold federal funding to the system until the Washington Metropolitan Area Transit Authority (WMATA), rebrands as the Washington Metropolitan Authority for Greater Access (WMAGA).

June 2, 2025 - The Hill

White and yellow DART light rail train in Dallas, Texas with brick building in background.

DARTSpace Platform Streamlines Dallas TOD Application Process

The Dallas transit agency hopes a shorter permitting timeline will boost transit-oriented development around rail stations.

May 28, 2025 - Mass Transit

Rendering of Shirley Chisholm Village four-story housing development with person biking in front.

San Francisco's School District Spent $105M To Build Affordable Housing for Teachers — And That's Just the Beginning

SFUSD joins a growing list of school districts using their land holdings to address housing affordability challenges faced by their own employees.

2 hours ago - Fast Company

Aerial view of Rancho Cucamonga, California with suburban commercial center and large palm trees at sunset with mountains in background.

Car-Centric LA Suburb Looks to a Train-Oriented Future

City leaders in Rancho Cucamonga, the future western terminus of the Brightline West rail line to Las Vegas, want to reimagine the city as a transit-oriented, pedestrian-friendly community.

4 hours ago - Bloomberg CityLab

Ground level view of Alaska Pipeline oil pipeline near Prudhoe Bay, Alaska with bare mountains in background.

New Alaska Bitcoin Mine Would Burn as Much Energy as the State’s Largest Coal Plant

Fueled by “stranded” natural gas, the startup hopes to become the largest in the US, and to make Alaska an industry center.

6 hours ago - Alaska Beacon

Urban Design for Planners 1: Software Tools

This six-course series explores essential urban design concepts using open source software and equips planners with the tools they need to participate fully in the urban design process.

Planning for Universal Design

Learn the tools for implementing Universal Design in planning regulations.