You’d have to live under a rock (completely sustainable housing) if you didn’t realize that climate change, and rapidly increasing energy prices are a hot topic in today’s world. But why is the focus on the building industry?

Buildings consume nearly half of all the energy produced in the United States.

Globally, the percentages are even higher. Which explains why much of Europe is paving the way in both commercial and residential energy-efficient building.

It’s important to understand that energy-efficient building is about more than energy-efficient materials. A great deal of planning is needed to ensure the proper integration of materials and design, to achieve the best possible outcome.

Energy-Efficient Building

Passive Design, and Net Zero Energy Building (NZEB) are the two primary concepts for energy-efficient building. Passive Design uses a combination of climate-based passive and active design strategies to minimize the usage of energy, materials, and water.

Passive homes focus on the absolute minimal amount of energy use possible to heat and cool the building.

In 2015, the Passive House Institute of the US released the only passive building standard based upon climate-specific comfort and performance. The goal was to find the right balance between the up-front investment in a passive build, and the long-term payback, to achieve the most comfortable and cost effective building possible. Learn more at phius.org.

The basic premise of a Net Zero Energy Building is that they generate as much energy as they consume.

Designed to minimize the amount of energy they need to operate, and with renewable energy systems that meet their energy needs. Solar, wind, and geothermal are examples of renewable energy systems.  Design considerations to achieve net zero energy include passive solar design, triple pane or triple glazed windows, and high performance building envelopes. The US Department of Energy Zero Energy Ready Home program has been working to promote Net Zero building since 2008. Learn more at energy.gov.

Both Passive Home and Net Zero Energy Home certifications are generally based on the HERS Home Energy Rating Score, and certified by third parties, such as the Living Building Challenge.  To learn more about the certification process, click here.

The Deep Energy Retrofit

Most of the discussion about passive or net zero design centers around new construction.  It just makes good sense to plan ahead for the future. However, considering that the majority of the building inventory in the US was built prior to 1990, there is even more opportunity for energy savings in renovating and retrofitting existing buildings.

As the experts at Green Building Advisor explain, the process usually begins with a home energy audit and building analysis. Energy usage reductions are achieved through a whole-building approach, including insulation, heating and cooling systems, lighting, appliances, and water usage. A typical simple energy retrofit focuses only on individual upgrades, like heating and cooling.

Deep Energy Retrofits are a whole-building approach to maximizing energy efficiency.

The key to success in a deep energy retrofit, is utilizing skilled building science professionals who have the experience planning the integration of these systems into existing structures. Look to organizations such as the Building Performance Institute to direct you to certified professionals in the industry. That’s how we found Bill McKnight, CEO, Energy Conservation Specialists.

WATCH:  Net Zero Deep Energy Retrofit with ECS and ThermalBuck  

With over 20 years in the field of deep energy retrofits, Bill has achieved both BPI Accreditation and Energy Star Certification, teaches building science at Ulster University in NY, and has been featured in Home Energy Magazine. To learn more about the historic renovation project we worked on with Energy Conservation Specialists, and see how ThermalBuck was used to create a thermally efficient building envelope, read the full installation story here.

The Poplar Network features a clear-cut piece by Rob Freeman that explains the difference between Passive and Net Zero. For a more detailed reference, an excellent resource is Net Zero Energy Buildings, by Steven Winters Associates, Inc., a respected authority on building science and efficiency. It was featured in 2016 in the The Whole Building Design Guide, a program of the National Institute of Building Sciences which focuses on the latest technology and “whole building” design techniques. Data was also sourced from architecture2030, whose mission is to address climate change problems with design solutions of the built environment.