Michael Green presents ‘The Case for Tall Wood Buildings’

Courtesy of

Driven by the desire to find safe, carbon-neutral and sustainable alternatives to the incumbent structural materials of the urban world, Michael Green, Principal at Michael Green Architecture, has shared with us this highly-anticipated feasibility study, The Case for Tall Wood Buildings. The 200-page document encourages architects, engineers and designers to push the envelope of conventional thinking by demonstrating that wood is a viable material for tall and large buildings and exposing its environmental and economic benefits.

Co-author Michael Green explains, “To slow and contain greenhouse gas emissions and find truly sustainable solutions to building, we must look at the fundamentals of the way we build – from the bones of large urban building structures to the details of energy performance. We need to search for the big picture solutions of today’s vast climate, environmental, economic and world housing needs.”

Courtesy of Michael Green Architecture

Mid-rise and tall buildings around the globe have been predominately constructed in concrete and steel, two materials that have served their purpose well. However, in the challenging age of Climate Change, it is imperative that we revolutionize our building industry, as the report reveals that “concrete production represents roughly 5% of world carbon dioxide emissions, the dominant green house gas. In essence the production and transportation of concrete represents more than five times the carbon footprint of the airline industry as a whole.”

The Case for Tall Wood Buildings introduces a new way of constructing tall buildings with a renewable, durable and strong building material that is manufactured by nature. When harvested responsibly, wood may be the best option for reducing greenhouse gas emissions and storing carbon in our buildings.

Courtesy of Michael Green Architecture

The study introduces a new construction model for tall buildings known as ‘Finding the Forest Through the Trees’ (FFTT). This structural solution utilizes mass timber panels – solid panels of wood engineered for strength through laminations of different layers – to achieve a much lighter carbon footprint than the functionally equivalent concrete and steel systems. Preconceptions of mass timber construction are acknowledged throughout the study, showing that this mass timber structures are capable of meeting fire and life safety needs while staying within cost competitive marketplace conditions.

Courtesy of Michael Green Architecture

The FFTT system is a predominantly wood system with a solid wood central elevator (and stair) core and wood floor slabs. Steel beams are used to provide ductility in the system to address wind and earthquake forces. Concrete has been used for the below grade areas of the structure. Architecturally, this system would allow for more flexible, open floor plans and thinner walls.

Ultimately, Michael Green plans to develop a 30-storey wooden tower in as an attempt to demonstrate the possibilities and advantages of mass timber construction for mid-rise (6-12 storeys) and tall buildings (+/- 3- storeys). He also believes that the continuation of this research will one day result in the possibly of using mass timber construction for even taller high rises.

Green has generously published the results of his research in an open source paper than can be reviewed in its entirety here. Check it out and let us know your thoughts!

The Case for Tall Wood Buildings was commissioned by CWC on behalf of the Wood Enterprise Coalition (a partnership of Wood WORKS! BC, FPInnovations, and BC Wood Specialties), with support from Forestry Innovation Investment, and prepared by mgb ARCHITECTURE + DESIGN, Equilibrium Consulting, LMDG Ltd, and BTY Group.

Co-authors: Michael Green MAIBC FRAIC of Michael Green Architecture (Formerly of mgb ARCHITECTURE + DESIGN) and Eric Karsh PEng of Equilibrium Consulting Inc (Structural Engineers)

Project Lead and Architects: Michael Green (mgb ARCHITECTURE + DESIGN)
Structural Engineers: Eric Karsh (Equilibrium Consulting Inc)
Structural Peer Review: Reed Jones Christoffersen Consulting Engineers
Costing: Joe Rykab (BTY Group)
Code Consultants: Geoff Triggs (LMDG Ltd)
Code Peer Review: GHL Consulting Ltd
Renderings: Seng Tsoi of Michael Green Architecture

Cite: Rosenfield, Karissa. "Michael Green presents ‘The Case for Tall Wood Buildings’" 27 Mar 2012. ArchDaily. Accessed 30 Oct 2014. <http://www.archdaily.com/?p=220779>
  • Richard Peck

    Not sure how mass harvesting of nature’s primary carbon absorbers, trees, contributes to carbon neutrality

    • Sam

      If you read the PDF, one of the first thing they talk about is the sustainability of timber harvesting in Canada. About 1% of trees are harvested and they must be replaced, by law.

    • Chillll

      It’s an interesting concept. The idea is that the trees as they grow, absorb the carbon dioxide. If they’re cut down, the wood will hold the carbon forever, until it decomposes or is burnt. If it’s burnt, it gets released back into the atmosphere, but if it decomposes, most of it goes back into the soil.

      So essentially, it really does work as a carbon sink, and is actually carbon *negative*, better than carbon neutral.

      As for mass harvesting of trees, this report is out of BC where they have a strong sustainable forestry industry.

  • Sam

    This is a nice move. If science could jump in to create genetically modified trees that grow faster and stronger, then we would have a truly sustainable solution.

    The problem with the current solution is that we are running low on large timber-grade trees and they take many years to grow.

    • Simon

      Science has been busy at work for decades. Sustainable tree plantations grow trees in some countries at at least double the rate compared to 50 years ago. Canada, however, will never be a great place to do that because it is too cold

  • A

    I think the idea is to use engineered wood products, rather than actual solid lumber.

    A quote from the PDF: “The important shift that this report will address is the fundamental difference between small-scale dimensional lumber solutions (light wood frame) and Mass Timber construction. Mass Timber is defined as solid panels of wood engineered for strength through laminations of different layers. The panels vary in size but can range upwards of 64 by 8 feet (20m x 2.4m) and in the case of CLT can be of any thickness from a few inches to 16 inches or more. Ultimately these are very large, very dense solid panels of wood.”

    It would be interesting to look at the actual lamination process and how harmful that is.

    • Sam

      It’s good in that it uses smaller pieces of wood to make bigger pieces, so you don’t have to cut down 100 year old trees.

      It’s bad in that it uses all kinds of nasty glues.

      It’s a give and take situation, they probably need to work on the glue technologies.

  • James Strong

    I haven’t read the PDF, but I wonder – does it address the safety of the construction site?

    I imagine timber is a much easier material to manipulate once in place than say – steel or concrete. But with all the on site cutting that would be required to construct a timber high-rise, I wonder about a) the breathability of the air during construction and b) the risk of dust fire.

    Just this year there was a dust fire that wiped out a BC sawmill.

    I feel like it’s a bizarre point to raise – but would that be an issue?

    • Robert Bierma

      the system is designed to have little or no cutting of the wood components

  • Mohamed Ouksili

    A high rise building needs to satisfy strength, comfort  and fire resistance  criteria. Using wood to achieve these three requirements is extremely challenging because of its mechanical/chemical properties. Now if we go for ” engineered” wood plates, this means that we will need an industry to change these same mechanical/Chemical properties to achieve the above requirements. As a preliminary though I am a litte pessimistic.
    1- To change wood properties we will need factories (carbon emission, possible usage of fossils/nuclear  energy …etc).
    2- using wood means that we will have to destroy more forests ( these same are the ones that transforms carbon into oxygen!).
    I am a bit pessimistic, on how green or cost effective it can be, but I will go through the idea.

    • Sam

      Have you analyzed the steel and concrete industry for comparison?

    • http://www.ptfnola.com julien

      Just for your info,

      wood has a better fire resistance than steel…

      World Trade Center, for example. The fire melting the steel is what caused it to collapse.

  • http://www.londonflooringsuppliers.co.uk Engineered Wood

    Engineered flooring can be direct glued down over dry concrete slabs above or below grade or stapled down over a wood sub-floor.