Grantee Research Project Results

2016 Progress Report: Green Oak as a Sustainable Building Material

EPA Grant Number: SU835729
Title: Green Oak as a Sustainable Building Material
Investigators: Shelton, Ted , Stuth, Tricia , Taylor, Adam M , French, Robert C. , Retherford, Jennifer , Bennett, Richard M , Collett, Brad , Schwartz, John , Stone, Mike , Kraus, Hannah , Starr, Royal , Edwards, Aren , Fleming, John , Lane, Camille , Leitch, Mary , Shedd, Joseph , Towe, Tucker , Wilson, Emilee , Johnson, Charlie , Short, Tyler , Lowe, Catherine , Spinning, Patrick , Royer, Christopher , Tilton, Andrew , Freeman, Jacob , Talley, Peter
Current Investigators: Shelton, Ted , French, Robert C. , Taylor, Adam M , Bennett, Richard M , Collett, Brad , Retherford, Jennifer , Schwartz, John , Stuth, Tricia
Institution: University of Tennessee
EPA Project Officer: Page, Angela
Phase: II
Project Period: October 1, 2014 through August 14, 2016 (Extended to July 31, 2017)
Project Period Covered by this Report: October 1, 2015 through September 30,2016
Project Amount: $90,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet - Phase 2 (2014) Recipients Lists
Research Category: P3 Challenge Area - Air Quality , P3 Challenge Area - Sustainable and Healthy Communities , Sustainable and Healthy Communities

Objective:

Objective: The primary objectives in Phase II are:

• To develop, detail, and construct a full-scale building using green oak pallet cants as structural members.
• To monitor, record, and analyze the demonstration project for structural, acoustic, and thermal performance over a two-year period as the green oak members dry.
• To disseminate our findings widely through multiple digital media platforms, peer reviewed publications, design award programs, and programs recognizing the integration of pedagogy and practice.

Progress Summary:

Through multiple courses and independent studies in the School of Architecture and College of Engineering and with technical assistance from the Department of Forestry, significant progress has been made toward the realization of Phase II objectives. This progress includes:

• Development and evaluation of a variety of enclosure and opening systems for the primary structural system (bent system).
• Development and evaluation of alternative mass timber structural and enclosure systems using the green oak cants.
• Limited exploration of steam bending techniques using strips cut from green cants to create structural and enclosure systems. (No successful results.)
• Exploration of the use of shou sugi ban, a traditional Japanese technique of charring wood, as a method for providing a protective exterior finish for the green oak.
• Additional break testing of cants to compare failure modes between new green members to that of members that have been drying for a year.
• Identification of a new community partner, the Children's Defense Fund, which has a campus near Knoxville, for future potential demonstration projects.
• Detailed examination of the structural use of green oak pallet cants in ancillary infrastructural projects' particularly bridges. This included the identification and evaluation of precedent projects, adaptation of lessons learned from precedents to green oak technologies, design of a demonstration project, structural engineering of demonstration project, and full size constructed mockup of a section of the demonstration bridge project.
• Both the enclosure and alternate structural systems as well as the bridge demonstration were presented to multiple panels of professionals including architects, engineers, landscape architects, and foresters for review, evaluation, and feedback.

Future Activities:

This is, of course, a time-based investigation requiring the drying of the oak members to fully evaluate the effectiveness of the proposed systems. As we now have some members that have been drying for close to two years and bits of structural systems that have been assembled for close to a year, some evaluation is beginning to be possible. A good example is the break testing comparing the performance of newly cut members to the performance of members that have been drying for a year. Results of that testing showed the anticipated rapid deflection of the drier member, but found these still to be within expected parameters. Additionally, continued visual inspection of the joints of the earliest constructed bays of the pegged bent structural system have found no concerning separation.

The demonstration of multiple methods for providing enclosure and openings in the bent-based structural system was an important milestone this academic year as flexibility in this regard is essential to this becoming a viable system. Demonstration of these critical components opened up an investigation to alternative structural and enclosure systems. While investigations into lightweight, steam-bent structural and enclosure systems were unsuccessful, explorations of mass timber construction techniques were highly promising and point to a fruitful architectural use of the material. This direction is not only in line with emerging research into mass timber construction paradigms for the US construction market but also holds the promise of using green oak cants more intensively in the building fabric, thus displacing an even greater amount of contemporary building products with this low-carbon alternative.

This semester's investigation into ancillary structural uses for the material for bridges opens up yet another area where, at least for pedestrian and light vehicular bridges, it is easy to imagine how green oak could supplant materials such as concrete and steel that have much higher energy and carbon profiles. Following this preliminary work on a demonstration project with a new community partner, we are very hopeful that a future path to in-situ construction of the project can be found. This would, of course, serve as an important additional proof of concept for the ideas explored in the research.

Journal Articles:

No journal articles submitted with this report: View all 2 publications for this project

Supplemental Keywords:

built environment, forest products, energy efficiency, embodied energy, housing, green design, environmentally benign substitute, conservation, design for the environment, green building, alternative construction material, architectural design

Relevant Websites:

The Green Oak Initiative Exit

Green Oak Revisited Exit

Progress and Final Reports:

Original Abstract

2015 Progress Report

Final Report

P3 Phase I:

Green Oak as a Sustainable Building Material  | Final Report