Iano's backfill

First, green roofs, next green walls?

In Portland, Going Green and Growing Vertical in a Bid for Energy Savings (New York Times online, January 30, 2010) describes the planned renovation of the Portland Edith Green-Wendell Wyatt Federal Building General Services Administration building. The project incorporates green fins, more than 200 feet high, that will support a vertical garden wall. Plant type will be selected to provide shade in the summer and increased light transmission in the winter. Questions of plant maintenance and irrigation are still being resolved. 

The $133 million project is being performed under the GSA's new Office of Federal High-Performance Buildings program. When complete, the building is predicted to consume 60 to 65 percent less energy than comparable buildings.

LEED Pilot Credits Program

USGBC's LEED credit piloting program provides a framework for testing and refining proposed new prerequisites and credits prior to their formal introduction into the core LEED rating systems. Building teams interested in making use of pilot credits can apply to participate in the program. Current pilot credits include:

Life Cycle Assessment of Building Assemblies and Materials

This credit seeks to encourage the use of environmentally preferable materials based on life-cycle analysis scoring. An approved Environmental Impact Calculator is used to assess materials in various assembly types, such as columns and beams, floors, exterior walls, windows, etc. Results of this assessment are transferred to a second calculator, the USGBC Credit Calculator, to determine a life-cycle impact score and number of LEED points to be awarded. Up to 5 points, plus 2 additional innovation points can be achieved.

A this time, the approved environmental impact calculator is the Athena Institute's Eco-Calculator for Assemblies.

PBT Source Reduction: Dioxins and Halogenated Organic Compounds

This credit is intended to discourage the use of materials classified as persistent bioaccumulative toxic chemicals (PBTs). PBTs are considered to have significant adverse health effects on humans because they are toxic, long-lasting, and given to accumulating in the biological food chain. The PBTs specifically targeted by this credit are halogenated organic compounds. Examples include plastics containing chlorine or fluorine (polyvinyl chloride, PVC, being perhaps the most commonplace example) and brominated or halogenated flame retardants.

This pilot credit appears to signify the USGBC's change in position regarding the environmental suitability of PVCs for use in building construction. See this blog's previous discussion of this issue in Complexities of Sustainability, November 2007.

Medical and Process Equipmenet Efficiency

This credit encourages the purchase of energy efficient medical and other types of equipment.

Innovative Ventilation

This credit encourages the use of mechanical or natural ventilation systems that improve occupant comfort and well-being while reducing energy consumption in comparison to conventional systems. Example potential technologies include displacement ventilation systems, low-velocity ventilation systems, under-floor air delivery systems, and natural ventilation designs.

Preliminary Integrative Project Planning & Design

This credit is intended to encourage innovative strategies for achieving integrative, cost-effective green design and construction methods. Two credits are included, the first applied to the programming and pre-design phases of a project, and the second for the following design and construction phases. These credits require early identification of LEED rating goals, institution of cross-disciplinary design practices, performance based incentives, and other sustainable building design best practices.

More Info

• LEED Pilot Credit Library
• EPA Persistent Bioaccumulative and Toxic (PBT) Chemical Program

Codes, Standards, & Specs

What are the differences between Codes, Standards, and Specifications, and how are they related?, from the Portland Cement Association's Concrete Technology FAQ, is a succinct description of how these three types of information interrelate. In short:

Codes:

Codes are legal requirements for building that are enforced by the local jurisdiction, such as city, county, or state. In the U.S., most building codes are based on the model codes published by the International Code Council, a private, not for profit, codes and standards development organization.

Standards

Standards are voluntary recommendations for good building practice that are usually developed and published by organizations with an interest in the construction industry. For example, AAMA/WDMA/CSA 101/I.S.2/A440-08, NAFS, North American Standard/Specification for windows, doors and skylights is a performance standard developed by a group of window and door industry trade associations. On its own, this particular standard is voluntary. But since it has become adopted by reference into the model building codes, its requirements have also become legally mandatory.

Specifications

Specifications are written documents that detail quality of materials and methods of construction. Specifications may be written by the design team and become enforceable as part of the construction documents for a construction project. Or, like standards, they may be written by any number of private parties and remain either voluntary, or, if adopted into the codes, become legally mandated.

ASTM Standards
ASTM is one of the leading publisher of construction standards. The executive summary of any ASTM standard can be found on the ASTM web site. From the home page, click on the Standards Search link--don't click on the Site Search link. Next, in the Search Standards box, enter the standard designation, such as "C150" and click Search. The first result listed is typically the current standard. Full copies of the standards are also available for purchase either in hardcopy or digital format.

Specifications Numbering
Most construction specifications are organized with a numbering system called MasterForamt, published by the Construction Specifications Institiute. For more information on this system, Need help with Masterformat specification numbering? From the Construction Specification Institute home page, follow links to Standards and Formats and look for links to MasterForma Numbers & Titles. The complete MasterFormat documentation is also available (for a fee) at www.masterformat.com.

The Delivery of Design and Construction Services

AGC-AIA Dispute Represents Deeper AEC/O Rifts (Cadalyst, Oct 25, 2007) discusses how changes in methods of project delivery, such as building information modeling, are leading to changes in the traditional roles of the designer and builder--changes that do not always come easily.

The upcoming 5th Edition of Fundamentals of Building Construction (due Fall of 2008) will have an expanded discussion of the roles of the building and construction manager in the construction of buildings.

More Info
Building Futures Council
The AGC's BIM Initiatives and the Contractor's Guide to BIM (AEC Bytes)

Carbon Neutral Building Design

Green Building Studio Inc. has launched version 3 of their Green Building Studio web-based software for analyzing the energy impacts of alternative building designs. According to GBS, in less than 3 hours you can register your project, submit your BIM building model, review results with your consultants, and tune building parameters to optimize the whole building energy use. The software addresses carbon neutral building, US EPA Energy Star scores, water usage, daylighting, natural ventilation, and other factors.

The BuildCarbonNeutral calculator estimates the C02 emissions of a proposed building based on its size, method of construction, and location. Jointly developed by Mithun Architects and the Lady Bird Johnson Wildflower Center, the tool purportedly:

estimates the embodied energy and subsequent carbon amounts released during construction. The measurements account for building materials, processes and carbon released due to ecosystem degradation or sequestered through landscape installation or restoration.

Accessibility and the IBC

The June 2007 Building Safety Journal is devoted mostly to accessibility regulations and the International Building Code, including discussion of:

• The 2006 IBC and 2003 ICC/ANSI A117.1 accessibility standard have been accepted by the US Department of Housing and Urban Development as a safe harbor for meeting HUD's Fair Housing Act design and construction accessibility guidelines.
• The US Access Board Committee's Courthouse Access Advisory Committee has issued a written report providing guidelines for accessible design in courthouses.
• The US Access Boards ADA and ABA standard continues to move toward adoption by the DOJ. (But the discussion of the application of various Federal agency guidelines leaves this author scratching his head.)
• Accessible design for new stadiums
• Elevators and accessible egress in tall buildings discussed, including ongoing study of elevator-assisted egress
• Theater accessibility
• Accessibility of sinks within work areas
• Differences among adoption of accessibility at the state level

For those dealing with these design issues, this issue of Building Safety Journal is worth a look.

Standards: New (costly?), New (better?), and Needed(?)

ENR's Third Exit Stair Could Make Highrises Too Costly to Build (June 4, 2007) reports on the adoption of more stringent life safety requirements for tall buildings in the 2007 Supplement to the International Building Code. Both the Building Owners and Managers Association International and the American Institute of Architects oppose as too costly a new requirement for buildings taller than 420 feet to have at least 3 independent exit stairs. Other changes to tall building requirements in the 2007 Supplement, all coming in the aftermath of the 9/11 attacks on the World Trade Center Buildings in New York City, include:

• protected fire service elevators and lobbies
• photoluminescent pathway markings in exit stairwells
• inspection and greater strength requirements for spray-applied fireproofing.

Proposals for progressive collapse resistance, increased  exit stairway enclosure integrity, and requirements for a a building's ability to burn without collapse were rejected. See the ICC's Code Development page for more information about that organization's code development process and the adoption of these new requirements.

In the same issue, Energy-Efficiency Guidelines Would Be National Model reports on the American Society of Heating, Refrigerating and Air Conditioning Engineer's (ASHRAE) ongoing development of Standard 89, an enhanced building energy efficiency guideline. Standard 89, now open for comments, is intended to reduce building energy consumption by 30% in comparison to ASHRAE's long-recognized Standard 90, and is being touted as a national standard for achieving LEED certified optimized energy performance. See ASHRAE's Advanced Energy Design Guides page for more about this organization's enhanced energy performance guidelines.

Lastly, Innovative Mix with Fly Ash is Still Not Widely Used describes a concrete mix composed of lime, portland cement, and fly ash developed by Nai C. Yang of the New Port Authority 38 years ago for use in airport runway construction. The mix is claimed to provide superior concrete and a reduction in environmental impact (due to reduction in cement content and, consequently, reductions in C02 emissions). However its broader use in airport construction has been hampered by unfamiliarity and a lack of standards for its production.

Green Construction News

Greenhouse (Eco-Structure, May/June 2007) reports on the National Association of Home Builder's (NAHB) February announcement of the development of a new residential building sustainability standard. To be produced in cooperation with the International Code Council, the new National Green Building Standard will be an ANSI certified consensus standard and will replace NAHB's current Model Green Home Building Guidelines.

Unlike the Guidelines, the new standard will be administered nationally, rather than at the local level, and will apply not only to single-family residences and townhouses, but to apartments and other types of multi-unit residential construction as well. Three levels of certification will be offered, Bronze, Silver, and Gold.

The standard is planned for release in February, 2008.

Trends and Challenges in Green Building (Building Safety Journal, April 2007) discusses coordination between sustainable design standards and building codes.

Historically, building codes have focused  on life-safety concerns and regulated construction so as to achieve immediately tangible benefits (such as higher resistance to fire or improved egress). More recently, some code requirements, such as energy efficiency in buildings, have been developed with the intent to provide benefits in the longer term and extending beyond the immediate users of the building.

Outside of energy efficiency regulations, coordination between long-term sustainability goals and building codes has been limited to date. Green building techniques relying on alternative building practices (for example, rammed earth construction) are frequently not addressed in the model codes. Green building programs, such as USGBC LEED or GreenGlobes, were originally formulated and continue to operate outside of the building code regulatory infrastructure.

Efforts to improve coordination between the model codes and sustainability initiatives include:

• Newer provisions within the codes themselves recognizing sustainable design practices such as insulated concrete formwork construction, unvented conditioned attics, waterless urinals, and greywater recycling systems
• Incorporation of energy efficiency standards meeting green building assessment criteria into the building codes, such as the proposed Standard for the Design of High-Performance Green Buildings Except Low-Rise Residential Buildings (ASHRAE/USGBC/IESNA Proposed Standard 189)
• The National Green Building Standard for residential construction, currently under development by the NAHB and the ICC (see above)
• Establishment of the USGBC committee Greening the Codes
• ICC's Industry Advisory Committee's comparison of Green Globes and LEED building assessment criteria (see Reports, IAC Task Group Report Green Buildings (March, 2007)

More Info
NAHB Research Center National Green Building Standard home page
ICC Green Building page

Model Code Cooperation Falters

Reversing previous reports, the International Code Council (ICC) has announced the suspension of efforts for the joint development of a single set of coordinated mechanical and plumbing codes in place of the competing codes currently published by itself and the International Association of Plumbing and Mechanical Officials (IAPMO). According to the ICC's September 1 press release, reconciliation of the two organizations' different code development processes was the major stumbling block. 

As this author understands it, the ICC accepts code change proposals from any interested party, but limits participation in final voting to governmental representatives (that is, ICC member building code officials). IAPMO permits a broader spectrum of participants, including consumers, governmental officials, and industry/manufacturer representatives, to have a say in final decision making. The ICC views their change process as less subject to the influence of special interests. Whereas IAPMO claims their process protects against any one group gaining undue advantage.

Regardless of the merits of either organization's claims, this author views the breakdown of this joint development process as a setback for the design and construction industry.

Really Fast-Built Houses

Record-Breaking Concrete--22-minute set (Concrete Construction, November 2005) reports on the 2 Hour House project in Tyler Texas. According to the article, the goal of the project was to construct a home from the ground up in less than two and one-half hours. Two  teams competed to complete 2160 sf homes including concrete slab on grade, three bedrooms, two baths, two-car garages, and full landscaping in the allotted time. Of particular note for readers of this particular publication, was the specially formulated concrete with a 22-minute set time.