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NEXUS’ blog features research, news, and commentary from industry leaders on green building and sustainable development. Syndicate content

Five Steps to Achieving Sustainability Success

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By Guest Contributor Patricia Calkins, Vice President of Environment, Health and Safety for Xerox Corp

During tough economic times, organizations today struggle to justify a meaningful investment in green initiatives, because they perceive the efforts will generate added costs, not concrete business benefits.

This misperception presents a major problem for global sustainability progress. In order to launch to launch and maintain a substantive sustainability strategy in a profit-oriented organizational structure, it must deliver a definable ROI...

Building Energy Modeling Software: Limitations to Envelope Heat Transfer Estimation

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By Ravi Srinivasan, CEM, LEED AP

Heat transfer through the building envelope is due to the temperature difference and may occur through one, two or all of the three heat transfer modes – conduction, convection and radiation. While conduction is based on the thermal property (thermal conductivity) of the envelope material and the temperature difference between the outside and the inside surfaces, convection occurs at the junction where the fluid (in motion) is in contact with the envelope surface. On the other hand, radiation arises when envelope bodies emit photons or radiant energy.

Green Product Association Welcomes First Global Trade Partners and Opens Tiered Membership

Aaron headshotGreen Building Product Promotion goes global; supports growth of companies of all sizes

CONTACT:
Aaron Desatnik
The Green Roundtable / NEXUS
617-374-3740 x 127
aaron@greenroundtable.org
www.nexusboston.org

Coming Full Circle: Reflections of a Recovering Architect

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By Barbra Batshalom, LEED AP, The Green Roundtable / NEXUS

Being the founder and Executive Director of a green building non-profit, most people tag me as an “environmentalist” and assume my motivations for leaving mainstream architecture were to save the planet, protect natural resources and improve public health. While these things are factors, they alone didn’t set my path.

My motivations were rooted in business – business planning and strategy of design and construction – and systems thinking – the dysfunctions I observed in the building decision-making process.

Given the challenges inherent in people working together  (the human condition), I still found it maddening that the basic concept and design approach to a project could be formulated without fully conceiving of its functional, operational and performance requirements.

How Inaccurate Is (Heat Transfer Estimate In) Your Energy Model? U-factor Calculation Methods for Building Envelope

Ravi headshotBy Ravi Srinivasan, CEM, LEED AP

Heat transfer methodologies can be largely classified based on the envelope material composition and heat transfer (spatial) dimensionality. In the material composition type, a mass wall and metal- or wood- framed wall may be categorized into separate groups. While a mass wall’s U-factor can be accurately computed using a “one-dimensional heat flow” method, the metal- or wood- framed wall require a “two-dimensional heat flow” method (ASHRAE 2009).

An Overview of Daylighting and Thermal Simulation Coupling: Still More Research Work Needed

Ravi headshotBy Ravi Srinivasan, CEM, LEED AP

Architects and Engineers employ Building Energy Simulation (BES) tools to determine building energy performance. BES tools such as ESP-r2 (University of Strathclyde, 2008) and EnergyPlus (Clarke and Janak, 1998; Crawley et al., 2002; US Department of Energy, 2008) help extend building design strategies to improve the energy performance of buildings. These tools have undergone strict validation procedures to ensure model and data accuracy for widespread use.

New Green Product Association Announces First Founding Members & Partners to Accelerate Market Transformation

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Founding members Xerox, CBC Flooring, Jandris & Sons, Bostik and Partners UL Environment and the Real Estate Journal lead the way in promoting sustainable products more effectively

  

Standing at the Crossroads: Moving Towards Transparency in a Greenwashed Industry

Barbra headshowBy Barbra Batshalom, The Green Roundtable / NEXUS

I remember the first time the concept of “green” edged its way into my consciousness.  It was about 18 years ago, when as an architectural designer,tasked to organize our product library and create a database. Digging through product information,

I came upon an article by BuildingGreen about the environmental impacts of rigid foam insulation and I thought…. “What?!”

Balancing Daylighting and Solar Heat Gain: Is this Realistically Possible?

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Solar radiant flux on the earth’s surface is an opportunity and an integral component of building energy consumption. Solar radiation incident on a fenestration system exhibits dual characteristics – both optical and radiometric. While solar-optical relates to the amount of light transmitted through the system, the solar-radiometric properties permit solar heat gain. At the occurrence of solar radiation on glazing, only the visible segment of the solar spectrum is perceptible to human eyes and contributes to spectral irradiance and illumination, which is referred to as “daylighting.”

Brain Teaser: Designing Energy-less Buildings

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These sample questions are based on Section 9 of ASHRAE 90.1 Standard, one of the sections an Energy Modeler has to be confident – especially issues such as “tradeable surfaces,” etc. However, one can become an expert through experience and continuous improvement.  Write to me if you have any questions or comments to ravi@greenroundtable.org. If you need the publication that compares energy simulation software, send me an email.

For those who are interested to learn EAc1 Energy Modeling “the right way,” join the two-day workshop I am conducting. Register here for the early registration discount!

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