What impact does window selection have on energy efficiency and sustainability?  What factors influence the energy performance of windows?  Populus Sustainable Design Consulting and SolarGlass Window & Door presented on these issues at last year’s USGBC Colorado Sustainability Conference.  Here is a description of that presentation:

The session will explain the implication of the DOE’s pending 2009 Energy Star changes for high altitude markets and review the product design responses planned by leading manufacturers.  Additionally, the session will discuss the interplay of the following factors on building envelop efficiency, sustainability, and occupant comfort: glazing to floor area ratios, dispersion of windows by elevation, glazing alternatives, frame materials, the often overlooked importance of quality installation

Attendees will come away with an understanding of what design elements should be given priority when developing a window solution for a given project, as well as the trade-offs associated with aesthetic, performance, and price considerations.

Included in the presentation will be an overview of the growing importance of performance-based measurements of building envelop efficiency (e.g.; Resnet’s Home Energy Rater modeling software) and how windows impact the HERS score.

USGBC Colorado has recently posted Populus & SolarGlass’s “Sustainable Window Selection” presentation on its website.  Of particular interest, on page 11 of the presentation, you will find a graph which demonstrates the specific concerns and trade-offs related to window selection for various ranges of desired HERS Index Scores.  Pages 13-18 contain a case study which analyzes the interaction of window selection and mechanical systems as it relates to home energy performance.

Populus is a full service sustainable design consulting firm that focuses on high performance, net-zero and near-net-zero custom residential and multi-family projects.  Populus guides architects and builders through the requirements of mandatory green building codes and optional green home certification programs, providing HERS rating, LEED for Homes Green Rater services and LEED for Homes training.  Visit Populus at www.popboulder.com.

All federal buildings to be net-zero by 2030?  That’s right!  On October 5th, as part of National Energy Awareness Month, President Obama issued an Executive Order that sets sustainability goals for federal agencies that focuses on making advancements in their environmental, energy and economic performance.

The President’s Executive Order requires that all federal agencies set greenhouse gas emissions reduction targets for 2020 within the next 90 days.  In addition, it requires that federal agencies increase their energy efficiency, reduce the petroleum consumption of their fleets, conserve water, reduce waste, support sustainable communities, and leverage their purchasing power to support sustainable products and technology.

Currently, the federal government is the largest consumer of energy in the United States (occupying 500,000 buildings and 600,000 vehicles).  In order to lead by example, the President’s Executive Order prioritizes the reduction of greenhouse gas emissions, requiring that all new federal buildings be designed to achieve net-zero energy use by 2030.  The Executive Order, among other things, sets targets to reduce vehicle fleet petroleum use by 30% by 2020 and to increase federal building water efficiency by 26% by 2020.

See the White House press release and the Executive Order (PDF 87 KB).

In proclaiming October as National Energy Awareness Month, President Obama called on the people of the United States to make clean energy choices that can rebuild our economy and make it more sustainable.  The President’s Executive Order demonstrates the government’s commitment to lead by example in implementing clean energy and advancing energy efficiency.  The President’s proclamation notes that the United States faces a turning point in its energy policy and that we can either allow climate change to wreak havoc, or we can create jobs by deploying low-carbon technologies to prevent the worst effects of climate change.  See President Obama’s proclamation.

Populus is a full service sustainable design consulting firm that focuses on high performance, net-zero and near-net-zero custom residential and multi-family projects.  Populus guides architects and builders through the requirements of mandatory green building codes and optional green home certification programs, providing HERS rating, LEED for Homes Green Rater services and LEED for Homes training.  Visit Populus at www.popboulder.com.