This Glossary has been compiled by Daniel A. Huard to include helpful terms and their descriptions that should be relevant to the Green Building, Development, Construction, Sustainability and Resiliency worlds.

This Glossary is copyright © 2018 Daniel A. Huard and has relied on the contributions of Green REsource Council of the National Association of REALTORS®

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Abandoned Property
property left behind intentionally and permanently when it appears that the former owner does not intend to come back, pick it up, or use it. One may have abandoned the property of contract rights by not doing what is required by the contract. However, an easement and other land rights are not abandoned property just because of nonuse. Abandoned land is defined as land not being used at the present time but that may have utilities and infrastructure in place.

A component of a solar thermal heating system’s collector which aids in converting radiant heat energy from the sun to heat energy the heat energy transmitted to the electrolyte (or water) due to its heat absorbing and concentrating ability.

Reducing or removing any kind of pollution.

Active Solar Heating
Systems that collect and absorb solar radiation, then transfer the solar heat directly to the interior space or to a storage system, from which the heat is distributed. There are two types of systems: liquid-based systems and air-based systems. If a system cannot provide adequate space heating, an auxiliary or back-up system provides the additional heat. Both air and liquid systems can supplement forced air systems.

Active Solar Power
A solar electric (photovoltaic or “PV”) system, not passive solar design, that converts the sun’s energy into electricity for the home. It is usually done with PV panels installed on the roof.

Active System
In a home, an active system is one that requires mechanical energy to work. Heaters and air conditioners are part of an active HVAC system. The opposite of an active system is a passive system.

Adapted Species Plant
vegetation that is not native to a particular region but that has characteristics that allow it to live in the area. Adapted plants do not pose the same problems as invasive species.

Added Antimicrobial Treatment
a substance added to a product (e.g., paint, flooring) to kill or inhibit the growth of microorganisms. Some products, such as linoleum, exhibit natural antimicrobial properties. Despite current practice, science has not proven that antimicrobial treatments reduce infection transfer in building finishes more effectively than standard cleaning procedures. Also known as added microbial agent. See U.S. EPA factsheet, Consumer Products Treated with Pesticides factsheets/treatart.htm

Any substance that is used to bond one surface to another surface by attachment. Adhesives include adhesive bonding primers.

Adjacent Site
a site having at least a continuous 25% of its boundary bordering parcels that are previously developed sites. Only consider bordering parcels, not intervening rights-of-way. Any fraction of the boundary that borders a water body is excluded from the calculation.

Advanced Framing / Concrete Construction
A construction method (also known as “Optimum Value Engineering” or “OVE”) that uses less material in the framing of a home and can reduce material costs and improve energy efficiency. Concrete construction involves using insulated concrete forms (ICFs) to create durable, efficient homes. The approach decreases the number of breaks in the thermal barrier of the building envelope. It also can save on construction costs because it is fast, especially compared with “stick built” homes.

Aerated Autoclaved Concrete (AAC)
Precast concrete that is cured by steam pressure inside a kiln called autoclave. The material is lighter weight than conventional concrete and has good insulation properties.

Agricultural Bi-products:
Products developed in agriculture but are not a primary product. This is often converted into building materials, such as straw used in wall panels or entire bales used as building blocks.

Agricultural Fibers:
Natural fibers, such as cotton, often used as insulation materials.

Air Quality Standards:
Amount of pollutants approved by predetermined guidelines that are not to be surpassed during a given time in a specific area.

Alternative Daily Cover (ADC)
material other than earthen material placed on the surface of the active face of a municipal solid waste landfill at the end of each operating day to control vectors, fires, odors, blowing litter, and scavenging. Generally these materials must be processed so they do not allow gaps in the exposed landfill face.

Alternative Energy
Alternative energy consists of those sources which are newer and less often used than conventional energy sources like coal and nuclear power.
Examples of alternative energy sources are wind, solar, and geothermal. These alternative energy sources are also examples of clean energy sources.
Building or retrofitting a home to use solar energy for hot water and/or to produce electric power, when combined with strategies to conserve energy, can drastically reduce a home’s ongoing utility bills.

Alternative Fuel
low-polluting, non-gasoline fuels such as electricity, hydrogen, propane, compressed natural gas, liquid natural gas, methanol, and ethanol

Alternative Water Source
non-potable water from other than public utilities, on-site surface sources, and subsurface natural freshwater sources. Examples include graywater, on-site reclaimed water, collected rainwater, captured condensate, and rejected water from reverse osmosis systems (IgCC).

Annual Sunlight Exposure (ASE)
a metric that describes the potential for visual discomfort in interior work environments. It is defined as the percentage of an analysis area that exceeds a specified direct sunlight illuminance level more than a specified number of hours per year.

American National Standards Institute (ANSI), American Society of Heating, Refrigerating and Air-Conditioning Engineers Inc. (ASHRAE), Illuminating Engineering Society of North America (IESNA) Energy Standard for Buildings. A nationally-recognized energy standard for commercial buildings.

An opening for the purpose of admitting light.

something subordinate to another, more important thing; adjunct; accessory.
In building roofing for example would be a built-in, nonstructural portion of a roof system. Examples include skylights, ventilators, mechanical equipment, partitions, and solar energy panels.

Appropriate technologies: Technologies that satisfy basic human needs while minimizing environmental impact. Appropriate technologies help communities be more self-sufficient by using small-scale systems that people can manage directly on a local level. Examples include locally created and decentralized (off-the-grid) renewable energy and farmer’s markets that sell regional, sustainably grown food.

Area Median Income
midpoint in the family-income range for a metropolitan statistical area, the non-metro parts of a region, or local equivalent to either. The figure often is used as a basis to stratify incomes into low, moderate and upper ranges.

a product formulated from multiple materials (e.g., concrete) or a product made up of subcomponents (e.g., a workstation)

Attached Greenhouse
A structure situated on a lower floor (or even below the first floor) and located on a home’s south side can provide passive solar heat to the home. Heat collected by the greenhouse at the lower level rises into the interior of the home by way of convection.

Attendance Boundary
the limits used by school districts to determine what school students attend based on where they live

Attic Fan
A fan typically mounted on the roof to create positive air-flow through an attic that does not rely on wind or require excessive passive venting. It is connected to a thermostat and operates automatically. Such fans offer several advantages. They:
1. Lower upstairs room temperatures by 10º;
2. Lengthen roof life by keeping shingles cooler;
3. Keep attics dry during the winter if they are installed with a humidistat;
4. Saves up to 30% on air-conditioning costs. (Savings vary by region and roof characteristics.)

Automated Dynamic Façade Systems
are daylighting control devices whose position or light transmission level can be automatically changed by a control system to address sunlight penetration or perceived glare in the space. Acceptable automated dynamic façade systems include interior automated window blinds or shades; exterior automated louvers, shades, or blinds; or automatically controlled dynamic glazing. Automated methods of sunlight penetration or perceived glare control do not include manually operated interior or exterior façade shading systems; manually operated dynamic glazing; or fixed exterior overhangs, fins, shades, screens, awnings or louvers whose position on the fenestration cannot be automatically changed or adjusted. Automated dynamic façade systems are allowed to have manual override but must default back to automated operation after a predefined period of no longer than two hours. Dynamic glazing is further defined in ASHRAE Standard 90.1 and the International Energy Conservation Code (IECC).

Average LED intensity (ALI)
the illumination output for light-emitting diode lamps, as specified in the International Commission on Illumination Standard 127–2007

An instrument, with a capture hood, that measures airflow from a mounted ventilation distribution diffuser.

Base Building
materials and products that make up the building or are permanently and semi-permanently installed in the project (e.g., flooring, casework, wall coverings)

Baseline Building Performance
the annual energy cost for a building design, used as a baseline for comparison with above-standard design

Baseline Condition(s)
before the LEED project was initiated, but not necessarily before any development or disturbance took place. Baseline conditions describe the state of the project site on the date the developer acquired rights to a majority of its buildable land through purchase or option to purchase.

Baseline Water Consumption
a calculated projection of building water use assuming code-compliant fixtures and fittings with no additional savings compared with the design case or actual water meter data

Basis of Design (BOD)
the information necessary to accomplish the owner’s project requirements, including system descriptions, indoor environmental quality criteria, design assumptions, and references to applicable codes, standards, regulations, and guidelines

Bicycle Network
a continuous network consisting of any combination of the following 1) off street bicycle paths or trails at least 8 feet (2.5 meters) wide for a two-way path and at least 5 feet (1.5 meters) wide for a one-way path 2) physically designated on-street bicycle lanes at least 5 feet (1.5 meters) wide 3) streets designed for a target speed of 25 mph (40 km/h) or less. Ensure that you read the current applicable requirements of the relevant Certification that your project is seeking.

Bicycling Distance
the distance that a bicyclist must travel between origins and destinations, the entirety of which must be on a bicycle network.

Bio-Based Material
commercial or industrial products (other than food or feed) that are composed in whole, or in significant part, of biological products, renewable agricultural materials (including plant, animal, and marine materials), or forestry materials. For the purposes of LEED, this excludes leather and other animal hides.

A material that is capable of decomposing naturally within a short amount of time.

A process that uses biological organisms to clean up contaminated water or soil; often used in oil-spill cleanup.

A landscape element, often a planted strip along a street or parking lot, for the purpose of capturing surface water runoff and filtering out silt and pollution before the storm water enters the drainage system or groundwater.

wastewater containing urine or fecal matter that should be discharged to the sanitary drainage system of the building or premises in accordance with the International Plumbing Code. Wastewater from kitchen sinks (sometimes differentiated by the use of a garbage disposal), showers, or bathtubs is considered blackwater under some state or local codes.

Block Length
the distance along a community block face; specifically, the distance from an intersecting Right-of-Way(ROW) edge along a block face, when that face is adjacent to a qualifying circulation network segment, to the next ROW edge intersecting that block face, except for intersecting alley ROWs.

the removal of makeup water from a cooling tower or evaporative condenser recirculation system to reduce concentrations of dissolved solids

Blower Door
A test that measures the air tightness of a building.

Abandoned, idle or underused industrial or commercial buildings where expansion or development is complicated by real or perceived environmental contamination.

BTU is an acronym for British Thermal Unit”. It refers specifically to the amount of energy needed to change the temperature of a pound of water by one degree Fahrenheit. This is the measure of power for many areas pertaining to home energy, including power, heating, and air conditioning.

BUG rating
a luminaire classification system that classifies luminaires in terms of backlight (B), uplight (U), and glare (G) (taken from IES/IDA Model Lighting Ordinance). BUG ratings supersede the former cutoff ratings.

Building Code
A building code is a set of minimum standards for building requirements, often pertaining to structural and fire safety. Building codes are generally set at the state level. Building codes help ensure that all construction meets an agreed-upon minimum standard of safety and comfort.
The term “building code” as it is commonly used rarely, if ever, pertains to green building issues nor to standards higher than minimum required.

Building Envelope
The separation between the interior and exterior environment of a building. Usually consisting of the roof, doors, windows, foundation, and walls.

Building Exterior
a structure’s primary and secondary weatherproofing system, including waterproofing membranes and air- and water-resistant barrier materials, and all building elements outside that system

Building Interior
everything inside a structure’s weatherproofing membrane

Buildable Land
the portion of the site where construction can occur, including land voluntarily set aside and not constructed on. When used in density calculations, buildable land excludes public rights-of-way and land excluded from development by codified law.

Building Science
Building science is the term applied to facts and theories of science pertaining to the construction and performance of buildings. The study of how a building’s systems function together under various environmental conditions in an attempt to achieve an ideal balance of comfort, health and safety. It is important to have a clear understand of building science in order to build high-performance, green, LEED Certified, Green Globes Certified, Living Building Challenge, Passive House-certified, sustainable buildings.  ASHRAE Audits serve an applied Building Science function in their assessment of heating and cooling systems, energy efficiency, ventilation and humidity control.

Built Environment
The man-made creation of, or alterations to, a specific area, including the environment where those changes are made. On a home site, this includes everything that has been disturbed during construction.

Built Green
A green building program in Washington state.

Bus Rapid Transit
an enhanced bus system that operates on exclusive bus lanes or other transit rights-of-way. The system is designed to combine the flexibility of buses with the efficiency of rail.

Carbon Dioxide (CO2)
The most prevalent of the greenhouse gases. Emitted by burning fossil fuels. Naturally occurring from sources such as human and animal respiration, ocean-atmosphere exchange, and volcanic eruptions.

Carbon Footprint
A calculation of the amount of greenhouse gases produced as a result of commercial, industrial, and individual activities. According to the EPA, “many of our daily activities – such as using electricity, using hot water, heating and cooling a home, driving a car, or disposing of waste – cause greenhouse gas emissions.”  The total of these emissions for an individual, household, organization, or company is known as its carbon footprint.

Carbon Offset
A system intended to equalize carbon production around the globe by trading greenhouse gas emissions–typically produced through fossil fuel consumption–for environmentally friendly actions, such as planting trees and using clean energy sources.

Ceiling Fan(s)
Fans, set to push warm air into living spaces, can reduce winter heating bills, and they can cut cooling costs when they are used in lieu of air conditioners.

A fibrous part of plants used to manufacture paper/textiles.

Cellulose Insulation
Insulation is made from recycled newspaper with borates to provide fire protection.

Cellulose Insulation – Post Consumer Recycled Content
Plant fiber that is used in wall and roof cavities to separate the inside and outside of the building thermally and acoustically. Typical materials used to manufacture the product include old newspapers, and telephone directories and borates and ammonium sulfate are included to retard fire and pests. Four major types of loose-fill cellulose products have been developed under a variety of brand names and are generally characterized as dry cellulose, spray applied cellulose, stabilized cellulose and low dust cellulose.

Central Vacuum System
Network of tubing with inlets throughout the house designed to remove debris to an out of the way receptacle. A central vacuum system is more efficient at the removal of dust and debris than traditional vacuums.

Certified Forest Product
A product certified as sustainable/suitable for use in a green building. These products are from a managed forest that has passed guidelines for responsible harvesting and environmental conservation.

Chain of Custody (CoC)
a procedure that tracks a product from the point of harvest or extraction to its end use, including all successive stages of processing, transformation, manufacturing, and distribution

Chain-of-custody Certification
A product that has met certain requirements throughout its life, beginning from its extraction and production all the way to its distribution and sale.

an intensive, multiparty collaborative session workshop that brings people from the project team’s different disciplines and backgrounds together to discuss, explore, generate, and collaboratively produce various design options related to all aspects the project’s development, goals and objectives.

ChloroFluoroCarbon (CFC)-based refrigerant
a fluid, containing hydrocarbons, that absorbs heat from a reservoir at low temperatures and rejects heat at higher temperatures. When emitted into the atmosphere, CFCs cause depletion of the stratospheric ozone layer.

Chemicals used in refrigeration, air conditioning, insulation, or as solvents and aerosol propellants. CFC’s are not eliminated in the lower atmosphere, and therefore they float into the upper atmosphere where their components deplete and destroy the stratospheric ozone layer.

CIR (Credit Interpretation Requests/Rulings)
A request specific to a Registered LEED Project seeking LEED Certification presented to Green Business Certification Inc. for the clarification project team’s proposed method for compliance attainment of a specific LEED credit(s) the project team may have question(s) about the path for attainment of. The CIRs are submitted via the interactive leedonline platform for the Review Team to assess at times with the assistance of the LEED Technical Advisory Group and at times the LEED Technical Committee as well.

Circulation Loop
A system that loops cold water back to the water heater (instead of down the drain) until hot water reaches the faucet. This is the primary component of a structured plumbing system.

Circulation Network (transportation)
all motorized, non-motorized, and mixed-mode travel ways permanently accessible to the public, not including driveways, parking lots, highway access ramps, and rights-of-way exclusively dedicated to rail. It is measured in linear feet.

Civil Twilight
the point in time in the morning (dawn) or evening (dusk) when the center of the sun is geometrically 6 degrees below the horizon. Under good weather conditions, civil twilight is the best time to distinguish terrestrial objects clearly. Before civil twilight in the morning and after civil twilight in the evening, artificial illumination normally is required to carry on ordinary outdoor activities.

Classroom or Core Learning Space
a space that is regularly occupied and used for educational activities. In such space, the primary functions are teaching and learning, and good speech communication is critical to students’ academic achievement. (Adapted from ANSI S12.60)

Clean Energy
Clean Energy is the term for sources of energy created from renewable sources with low environmental impact that do not emit pollution in order to produce that energy. Geothermal, solar, hydro, and wind are all clean energy sources.

Clean Waste
nonhazardous materials left over from construction and demolition. Clean waste excludes typical building contaminants including lead and asbestos.

Clear Glazing
glass that is transparent and allows a view through the fenestration unit or assembly. In contrast diffused glazing allows daylighting yet distorts the view.

Climate Change
Also called climate destabilization or greenhouse effect, this term represents the adverse effects of greenhouse gasses on long term weather patterns.

Closed Cell (spray) Foam insulation (ccf)
Closed Cell (spray) Foam (ccf) insulation is a very efficient type of insulation that also acts as a moisture and air barrier but which is more expensive than traditional types of insulation. Sometimes a small amount of ccf is used in combination with other insulation to get the most cost-efficient energy-efficient insulation in a given space.

Closed-Loop Cooling
a system that acts as a heat sink for heat-rejecting building and medical equipment heat by recirculating water or other electrolyte. Because the water or other electrolyte is sealed within the system, some closed-loop cooling systems use nonpotable water (such as recycled process water harvested from an air handler’s cooling coil condensate).

Closed Combustion
A design for combustion equipment (e.g. furnaces, water heaters) in which the air provided to the combustion equipment is ducted from the outside, and all exhaust gases are ducted directly to the outdoors. All elements of the system are sealed to prevent leakage of combustion exhaust into the home.

Coheat Test
A test that measures the distribution of heating and cooling systems throughout a building. Measures the overall heat loss factor. The home is alternately heated with the furnace and an array of small heaters (co-heaters) to calculate heat-delivery efficiency.

Color Rendering Index
a measurement from 0 to 100 that indictes how accurately an artificial light source, as compared with an incandescent light, displays hues. The higher the index number, the more accurately the light is rendering colors. Incandescent lighting has a color rendering index above 95; standard high-pressure sodium lighting (such as orange-hued roadway lights) measures approximately 25; many fluorescent sources using rare earth phosphors have a color rendering index of 80 and above. (Adapted from U.S. ENERGY STAR)

Combination Oven Discharge
water released from an oven that includes a steam cycle or option

Combined Heat and Power
an integrated system that captures the heat, otherwise unused, generated by a single fuel source in the production of electrical power. Also known as cogeneration. (Adapted from U.S. Environmental Protection Agency)

Combustion Exhaust Gases
The most common gases resulting from fossil fuel combustion include carbon dioxide, sulfur dioxide, and a number of sulfur dioxides. These gases can be dangerous if allowed to build up indoors.

Commingled Waste
building waste streams that are combined on the project site and hauled away for sorting into recyclable streams. Also known as single-stream recycling.

A quality assurance process of verifying and documenting that a building and all of its energy and resource consuming operable systems and assemblies are planned, designed, installed, tested, operated, and maintained to meet the owner’s project requirements and under testing they are operating as intended by the building owner complying to the design and sequence of operations defined by its design engineers, and the architect. Typical components and systems commissioned include heating, ventilating, air conditioning (HVAC), electrical, plumbing, safety, security

Commissioning Authority (CxA)
the individual designated to organize, lead, and review the completion of commissioning process activities. The CxA facilitates communication among the owner, designer, and contractor to ensure that complex systems are installed and function in accordance with the owner’s project requirements. Owners should always engage an ANSI-ASHRAE Accredited Commissioning Professional to ensure the highest levels of credibility and professionalism.

Compact Fluorescent Lamp (CFL)
Small fluorescent light bulbs that can be used in place of incandescent light bulbs typically due to their self-contained ballast. CFLs consume significantly less electrical energy than as well as last 8–10 times longer than incandescent bulbs. CFL bulbs are a transitional technology that is more energy efficient than incandescent light bulbs, not as energy efficient as LED light bulbs and have performance issues such as flickering and taking time to reach full brightness. They also contain mercury, a poison, which makes proper and safe disposal difficult. (Green from an energy standpoint but not from a toxic waste standpoint)

Compensating Shower Valves
compensating valves are designed to keep bathing water
temperature in the shower fairly constant when other appliances such as a washing machine or toilet are in use and when the hot or cold water supply pressures change or the bathing water outlet temperatures changes. These types of valves are available~
-Thermostatic Compensating Valves are designed to keep bathing water temperatures in the shower fairly constant when other appliances such as a washing machine or toilet are in use and when the hot or cold water supply pressures change or the bathing water outlet temperatures changes. The response of this type of mechanism is different to that of a pressure balance compensating valve.
-Pressure Balance Compensating Valves are designed to keep bathing water temperature fairly constant when other appliances such as a washing machine or toilet are in use and when the hot or cold water supply pressures change.
-Conventional, Non-Compensating Valves are completely dependent on the user to adjust the temperature at all times by changing the adjustment.

Composite Wood
A product consisting of wood or plant particles of fibers bonded together by a synthetic rein or binder. Examples include plywood, particle-board, OSB, MDF, and composite door cores.

An organic fertilizer made by a composting process wherein bacteria in the soil is mixed with degradable trash.

Conditioned Space
An interior space that utilizes any method or air conditioning or heating to control the temperature and/or humidity levels. CFA is generally used to determine a building’s habitable floor area. [See California Code of Regulations, Title 24, Section 2-5302]

the measurement of the level of dissolved solids in water, using the ability of an electric current to pass through water. Because it is affected by temperature, conductivity is measured at 25°C for standardization.

Construction Impact Zone
the project’s development footprint plus the areas around the improvement where construction crews, equipment, and/or materials are staged and moved during construction

Conventional (designed) Home
A conventional home is one that is built to meet Building Code standards. It meets minimum requirements for safety and comfort. By a large contrast a green, high-performance home, such as a Net Zero or Zero Energy Ready, LEED Certified or Passivehaus home, is one that meets much higher energy and resource performance standards.

Conventional Irrigation
a region’s most common system for providing water to plants by nonnatural means. A conventional irrigation system commonly uses pressure to deliver water and distributes it through sprinkler heads above the ground.

Conventional Turf
Grass that requires considerable watering, mowing, and/or fertilizers. What is considered conventional may very by region, but turf should be classified as ‘conventional’ if it is a monoculture and requires regular irrigation, chemicals, or significant mowing.

Cool Roof: Specialized roofing materials designed to reflect the heat of the sun away from
building this reducing the cooling load and associated air conditioning costs.

Cooling Tower Blowdown
The used turbid water discharged from a cooling tower typically because increased salinity or alkalinity has caused scaling. Cooling tower blowdown may be too saline for use in landscape irrigation.

Covenants, Conditions, and Restrictions (CC&R)
limitations that may be placed on a property and its use and are made a condition of holding title or lease. Home Owners Associations impose CC&Rs on properties that are parts of their respective developments that set rules and limitations on what an owner is permitted to do with their respective properties.

A procedure that advocates the recycling of waste materials into new products rather than permanently disposing of them.

Cradle-to-Gate Assessment
analysis of a product’s partial life cycle, from resource extraction (cradle) to the factory gate (before it is transported for distribution and sale). It omits the use and the disposal phases of the product.

A procedure advocating the disposal of waste materials by means of landfill, incineration, etc. rather than recycling.

a segment of the circulation network that terminates without intersecting another segment of the circulation network

Cultural Landscape
an officially designated geographic area that includes both cultural and natural resources associated with a historic event, activity, or person or that exhibits other significant cultural or aesthetic values

Current Facilities Requirements (CFR)
In an Existing Building the operational document developed following the implementation of the owner’s project requirements as applicable, developed to confirm the owner’s current operational needs and requirements

For the purposes of PEER, this refers to the consumer served by the grid operator. For city projects, this includes customers of all classes billed by the utility, municipality or third-party supplier. For campuses, this includes business and groups of individuals (i.e., building tenants, or university departments) that are served by the grid operator. In the case where the building owner is the grid operator, “customer” refers to the individuals or groups of individuals on the consumer side of the meter, regardless of billing practices.

Department of Energy (US DOE)
While to DOE has many areas of responsibility, relative to Green Homes, the DOE has a program called Zero Energy Ready Homes with set standards for homes, that with a modest solar array (added when the home is built or after) are capable of being Net Zero Homes, essentially producing as much clean energy as it may pull from the power grid.

the application of natural light within a building to aid in the reduction of energy used for lighting, the assistance with supporting circadian rhythm, the addition of a biophilia element. By using various methodologies within the design of a building we can use natural sunlight illumination to our benefit and advantage as this light decreases reliance on electricity by using windows and skylights as a connection to the exterior.

Dismantlement of a building so that components can be reused and recycled.

Demand Controlled Circulation Pump
circulation pumps use looped systems to ensure hot water is immediately available while keeping unused cold water in the system. The demand controlled circulation pumps uses a switch or motion sensor to automatically activate the circulation of water, thus it saves water and energy.

Designed Landscape
Traditional landscape features that have been incorporated into the home site. Designed landscape features may include soft-scapes (e.g. grass, shrubs) or hard-scapes (e.g. rocks, fountains), but do not include driveways or areas under roof. Designed landscape also does not include preserved natural areas.

Demand Limit Controller
The way the demand controller controls loads is called the load control strategy. It is the definition of each load’s importance in relation to all other loads being controlled by the system. Generally, there are three load control strategies: priority (fixed), rotating or combination.

Design for the Environment (DfE)
An environmentally sensitive design model which reducing environmental damage through careful planning and material selection.

Disturbed Lot Area
Area of the lot that is directly affected by construction activity, including any activity that would lead to soil compaction or damage to vegetation.

Diverted Waste
Waste from construction or demolition that is not sent to a landfill or incinerator. Strategies for diverting waste include reclamation, recycling, or for certain materials mulching.

Domestic Hardwood
Deciduous trees whose wood is the only in the U.S. and where the growth of new trees exceeds the removal rate.

Double Pane Windows
a window assembly that utilizes two panes of glass separated by a spacer bar having a sealant applied to hold the assembly together creating an “insulated glazing unit”. Double or triple pane glass windows often contain argon, krypton, or other gases between panes to reduce heat flow and improve insulation additionally the glass can contain coatings like “Low-E” to reduce radiant energy transfer or exterior colored reflective coatings.

Drip Irrigation System
An irrigation system that slowly applies water to the root system of plants to maximize transpiration while minimizing wasted water and topsoil runoff. Drip irrigation usually involves a network of pipes and valves that rest on the soil or underground at the root zone.

Drought Tolerant Plants
Species of plants, shrubs and vines which generally do not require additional watering in order to thrive in their native habitats. Landscapes with drought tolerant plants usually require little or no watering.

Drywall Clips
devices to provide support for drywall at corners while eliminating the need for excessive wood backing.

Dual Flush Toilets
Toilets with two buttons or a flush valve with two flush option positions, one for intended for liquid and another for solid waste. The liquid waste option uses less water per flush.

Duct Blaster
A test that measures the air tightness of heating and cooling ducts.

The ability of building or any of its components to perform its required function in its service environment over the period of time without unforeseen cost for maintenance or repair.

Dust Spot Efficiency
A measure of a filter’s collection efficiency for fine particles.