Seeing the Urban Forests for the Trees: Secondary benefits of our cities’ wood

The green forest
Another clear benefit of using urban lumber is the ability to gain credits from sustainability programs. With the U.S. Green Building Council’s (USGBC’s) Leadership in Energy and Environmental Design (LEED) program, credits can be easily claimed for Materials and Resources (MR) Credit 5, Regional Material Use.

MR Credit 7, Certified Wood, is a more problematic credit to obtain. The difficulty arises in the lack of an established recognition by the Forest Stewardship Council (FSC) of urban wood. At press time, FSC had announced there will be a motion offered at its General Assembly to be held in Seville, Spain, in the fall to ‘capture’ urban wood as part of the supply stream. Many issues will have to be resolved to establish the type of recognition, but this is a positive event that was not expected by many in the urban wood community for at least another three years.

The designer’s role through this process is that of educator and facilitator. They need to ensure the contractor (and the related subcontractors) is aware of this special product and that additional care may be required during bidding and fabrication. They also need to make certain owners are aware this unique, sustainable resource is available and can be an asset to the completed project. As mentioned, the designer needs to be much more hands-on to facilitate the proper use of the urban lumber. It is akin to working with a fine marble slab—the goal is to capture as much of the intrinsic drama and beauty possible from a natural and non-uniform material.

Specifications
Specifiers have a key role in ensuring urban lumber is correctly specified and incorporated in the project. Typical sections that would be used are MasterFormat 06 20 00–Finish Carpentry, 06 41 00–Architectural Casework, and 09 64 00–Wood Flooring. A small but important addition to a standard master specification should be a brief definition such as:

Urban Lumber: Wood that is obtained from trees located in cities, towns or suburbs not harvested for their timber value, but removed because of insect, disease or circumstance.

This will help clarify the material, distinguishing it from salvaged lumber, which may be collected from an existing building, or from rivers and lakes.

Other key areas should be inserted into a specification section depending on the level of desired aesthetic control. They include:

• samples of adequate size and length to show the range of acceptable color, grain, and acceptable flaws;
• pre-fabrication meeting, where the designer, owner, contractor, and millworker meet to establish the quality of the finish work;
• mockup approval of casework, paneling, or flooring to verify the desired quality level;
• list of approved mills or suppliers that deal with urban wood near the project; and
• clarification of the grade (or lack thereof) provided by the mill or supplier for the urban wood—NHLA grades are probably the best source for these, but there is no recognized grade for log-run material (it should be listed to give the cabinet shop an idea of what to expect).

Another important provision, especially for casework or stairs, is to use (AWI/AWMAC/WI) standards to define the expected quality standard of the completed work. These standards control the amount of grain and color-matching between members to ensure a uniform appearance is achieved (or not achieved, depending on the designer’s intent). This is especially the case when using wood such as ash that can have a broad variety of color and grain pattern within the same board.

When the designer is aware of the possibilities, a truly remarkable piece of casework or paneling can be achieved. By utilizing urban lumber, owners can attach a great story and add a unique component to any building.

Conclusion
From the disaster of emerald ash borer infestation emerges new opportunities to enrich urban spaces and provide new memories from city trees. Architects, contractors, and owners have the ability to use and promote this unique resource, but as with any ‘new product,’ the various parameters must be understood for its correct use to achieve the best results for all involved.

Provided design/construction professionals and urban forestry workers know the ideal criteria for board length, importance of identifying special cuts early, and the need to sort or grade material prior to delivery to fabricators to minimize waste results, urban lumber has great opportunity for richer character in the wood, making for a unique finish with a great back story.

Notes
¹ This comes from Therese Poland and Deborah Therese’s April/May 2006 article in Journal of Forestry, “Emerald Ash Borer: Invasion of the Urban Forest and the Threat to North America’s Ash Resource.” (back to top)
² See Marianne Rzepka’s August 22, 2010 article in the Ann Arbor Chronicle, “Seeds and Stems.” (back to top)
³ For more information, visit www.semircd.org. (back to top)
⁴ The project was profiled in Bradford McKee’s October 6, 2009 article, “Traverwood Branch Library,” which appeared in Architect. (back to top)

J. Gerard Capell, FCSI, AIA, CCS, is principal of Capell Design Associates in Milwaukee, Wisconsin, providing architectural design and specification writing services. His experience has broadly evolved from his work in California, Wisconsin, and Florence, Italy; this includes work as a rough and finish carpenter, architect, and specification writer on healthcare, education, civic, residential, senior living, retail, and industrial projects. Capell has served on CSI’s Certification Committee and Board, along with positions at the region and chapter level over his 28 years as a member. He can be reached at jgcapell@wi.rr.com.

FOLLOW
Wood