What is all that Green Stuff?

Green homes are designed to minimize environmental impact and maximize resource efficiency. The design, construction, and operation of a home in today's market must focus on energy, water, and resource efficiency while taking into consideration the indoor environmental quality and overall impact on the environment.

Below you will find links and definitions for common green building terms.

Green Building Organizations:

LEED (Leadership in Energy and Environmental Design): National rating system developed by the USGBC (United States Green Building Council) for recognizing highly efficient and sustainable structures. LEED is a voluntary program that has different levels of qualifications and is based on a point system. www.usgbc.org

NAHB National Green Building Program: Green Building programs from the National Association of Home Builders. NAHB also offers a Certified Green Professional (CGP), a designation designed to teach building industry professionals strategies for incorporating green building principles into homes, including an understanding that demonstrates enhanced environmental impact and increased performance and health benefits. www.nahbgreen.org

Energy Star: Environmental Protection Agency and Department of Energy’s program to help consumers identify energy-efficient products. Energy Star is a badge attributed to products that have water and energy efficient features. www.energystar.gov

Energy & Environmental Building Alliance (EEBA): Provides education and resources to transform the residential design, development, construction and remodeling industries to profitably deliver energy efficient and environmentally responsible buildings and communities. www.eeba.org

California Green Building Initiative: California is a progressive state with its energy efficiency, conservation, sustainability, green building and green purchasing practices. In addition California’s Title 23 specifies a number or energy saving requirements for building. The "Green Building Initiative," calls for state buildings to be 20 percent more energy efficient by 2015 and encourages the private sector to do the same. www.green.ca.gov

Green Terminology:

Energy Efficiency: The Dept. of Energy offers many resources and programs to assist in the area of Energy Efficiency & Renewable Energy: www.energysavers.gov

Heat Loss: Heat Loss calculations are typically required for new construction. The Dept. of Energy has a program to assist called Rescheck. I use this tool, to quickly capture and record a home's energy load and compliance.

Solar Gain: Increase in temperature contributed to a space by the sun’s rays.

Low-E (Low-Emissive): Coating applied to glass that allows light through but reflects heat, helping control seasonal interior temperature fluctuations due to solar loss and gain.

Glazing: Light transferring portion of a window or door. It is important to consider the thermal and light filtering properties of glazing for energy efficiency and protection of interior.

U-Factor: The rate of heat loss is indicated in terms of the U-factor (U-value) of a window assembly. The insulating value is indicated by the R-value which is the inverse of the U-value. The lower the U-value, the greater a window’s resistance to heat flow and the better its insulating value. Often times you need a minimum U-Factor for tax and energy credits.

R-Value: Measurement of the thermal resistance of a material, frequently referenced as a measurement for insulation. An example of higher R-Values for residential building might be: R-50 ceilings; R-21 walls; R-30 floors. See Recommended Levels of Insulation to determine what is most cost-effective for your home.

CFL (Compact Fluorescent Lamp): CFLs use 75% less electricity than incandescent bulbs but also contain a small amount of mercury and should be recycled. In most cases, these lights cannot be placed on a dimmer – so be aware for those applications.

LED (Light-Emitting Diode): LEDs are also known as solid state lighting. LEDs use much less electricity than both incandescent and compact florescent lights are clearly an emerging trend. Learn more about LED lighting at: lightingfacts.com

Building Materials & Techniques: There is currently a wide range of building materials and techniques available to support green building. As new technologies emerge, expect to see more options becoming available.

Advanced Framing Techniques: a framing technique intended to reduce the quantity of framing materials required while at the same time increasing the insulation cavity areas and limiting thermal bridging. Learn more at the US Dept. of Energy.

ICF (Insulated Concrete Form): Stackable, permanent concrete forms that have insulation on the outer and inner sides. Concrete is pumped into the cavity to create walls that have higher insulation values than standard pour concrete walls.

SIP (Structural Insulated Panel): Considered both a composite and modular system, SIPs are prefabricated systems used primarily for walls and roofs. SIPs employ composite materials, reduce waste through modular construction methods, achieve high insulation values, and may be used instead of many conventional building methods.

Modular Building: Technique that uses standardized components as a building practice. Modularization can occur as pre-constructed components, or as pre-defined rules for construction, such as spacing. This technique is a good method for reducing waste and making the building process more efficient, saving time and money.

Local/Regional Materials: Products harvested and produced within a specific distance from the building site, typically 500 miles. Using local materials is an important green building practice because is supports the community economy and reduces transportation related impacts on the environment.

Certified Lumber: Describes lumber that has been sustainably harvested by the Forest Stewardship Council.

Engineered Lumber/Wood: Composite wood products that include materials which would otherwise have been considered waste, including smaller trees. Encourages more sustainable forestry practices and protects Old Growth forests. Some engineered products are also designed to be stronger than standard lumber of equivalent size.

Composite & Recycled Materials: Composite materials have the advantage of being able to leverage reclaimed or recycled products that are not able to function structurally in their current state. Examples of composites include Recycled Glass Surfaces and OSB sheathing.

Passive Design: Considering the thermal processes of convection, conduction, absorption, and radiation in a design to maintain comfort levels and reduce or eliminate the need for mechanical systems for these purposes.

Passive Heating: Channeling the heat of the sun into natural thermal processes like radiation, conduction, and convection to heat a structure instead of relying on a mechanical heating system.

Passive Cooling: A design where ventilation and the retention of cool air are optimized instead of relying on a mechanical cooling system.

Passive Ventilation: Using the convective nature of warm air and the ability to control windows and vents as the environment changes to control air floor in a structure.

Porous Paving: Hard surfaces that allow rainwater to infiltrate its surface and to reduce runoff, erosion and contamination of surface water.

Rainwater Harvest: Systems implemented which capture and collect rainwater (from roof drainage for example) for use on-site. Some systems filter and purify the water, while others provide a means to distribute it, as in irrigation.

Xeriscaping: Landscaping technique which employs native and drought-tolerant plants in order to reduce water needs and help preserve native species.

Renewable Energy: Energy sources that are naturally replenished, examples are Solar, Wind, and Geothermal. In some cases, energy self-reliance that avoids all reliance on public utilities is referred to as "Off-the-Grid". Several tax credits are available.

Geothermal Heat Pump: Uses the constant temperature of the Earth’s interior to efficiently control the heating and cooling of a structure.

Heat Recovery System: Mechanical system used to reclaim and recycle wasted heat from other sources in order to reduce the need for the primary energy source.

Daylighting: Design practice that uses sunlight to reduce or removed the need for electric lighting. Elements to consider include orientation and placement of windows, light shafts/tubes, skylights, clerestory windows, reflective surfaces, and interior passage of light between rooms.

Carbon Footprint / Neutral: Measured in units of Carbon Dioxide (CO2), a measurement of impact on the environment. Carbon Neutral is emitting no carbon dioxide into the atmosphere, or alternately adopting practices that absorb or offset the carbon dioxide that is produced. Planting trees is one way to help offset your carbon footprint.

Construction Waste Management: Adoption of strategies to control and reduce the amount of waste generated at a job site. Techniques include reusing and recycling, as well as careful planning to reduce excessive waste.

Maintenance: Green products and structures feature low- or no-maintenance materials and designs that reduce the resources required for their continued use. Ease of maintenance also reduces the likelihood that replacement will be needed.

Sick Building Syndrome: Ill-health or discomfort caused by a structure’s design and/or the materials used to construct it. Factors contributing to SBS may include inadequate ventilation and chemical contaminants.

VOC (Volatile Organic Compound): Carbon compounds that vaporize at room temperature, and often contribute to poor air quality in a space. Off-Gassing is the release of volatile, toxic chemicals by products after installation. Off-gassing can be reduced by selecting no- or low-VOC products, avoiding problematic chemicals (such as formaldehyde), and controlling indoor temperature and moisture. Choosing pre-finished materials also helps to prevent the exposure of off-gassing to the design.

Source:

What Does Green Really Mean? (Fine Homebuilding Magazine)