ECOBROWNSTONE: The Art of Brownstone Greenovation - http://www.ecobrownstone.com
Glossary
http://www.ecobrownstone.com/articles/7/1/Glossary/Page1.html
Staff Writer
 
By Staff Writer
Published on 04/24/2008
 
Glossary.

An air barrier is any material that restricts air flow. In walls it consists of an exterior layer of sheathing and either building paper or house wrap, or board insulation, and on the interior it is usually sheetrock/wallboard or plaster. To be effective, it must be contiguous and continuous across the entire building envelope, with all holes and cracks fully sealed, and it must be in full contact with the insulation.  See our Article Insulation and the Building Envelope:  Controlling Heat Loss and Gain 

Annual Fuel Utilization Efficiency (AFUE) measures the amount of heat actually delivered to your home compared to the amount of fuel that you must supply to the furnace or boiler.

Asbestos is a mineral fiber – an impure magnesium silicate that occurs in a fiber form -- that has been used in building construction materials for insulation and as a fire-retardant. EPA and CPSC have banned several asbestos products, and manufacturers have also voluntarily limited uses of asbestos. Today, asbestos is most commonly found in older homes, in pipe and furnace insulation materials, asbestos shingles, millboard, textured paints and other coating materials, and floor tiles. Disturbing the asbestos during removal, cutting or sanding when renovating, can release the fibers into the air and endangering people who become exposed. Exposure can lead to long term health risks including mesothelioma (a cancer of the chest and abdominal linings), and asbestosis (irreversible lung scarring that can be fatal).  For further information see the EPA's guide An Introduction to Indoor Air Quality: Asbestos.  Also see our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination  

ASHRAE American Society of Heating, Refrigeration and Air-conditioning Engineers.

Biological contaminants include bacteria, molds, mildew, viruses, animal dander and cat saliva, house dust, mites, cockroaches, and pollen (see more about Asthma triggers at www.epa.gov/asthma).  Also see our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination 

Blower Door Test. The blower door test places a home under a known pressure by placing a large sealed fan in an exterior doorway and blowing air out of the house to create a vacuum. Instruments then measure how much airflow is required to maintain the pressure difference between indoors and outdoors. The tighter the house, the less air the blower door must move to maintain a given pressure. Besides measuring the airtightness of the house, it also helps to pinpoint the location of specific air leaks by feeling with the hand or with a smoke puffer or infrared imaging.  See our Article Insulation and the Building Envelope: Controlling Heat Loss and Gain

building envelope -- the building's roof, walls, windows, and doors, roof and foundation, in other words the envelope, or separation, that controls the flow of energy between the interior and exterior of the building.  See our Article Insulation and the Building Envelope: Controlling Heat Loss and Gain

Carbon monoxide (CO) is an odorless, colorless, tasteless, invisible gas produced by incomplete oxidation in a combustion process.  See our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination 

Central manifold distribution system is a hot water system in which hot water enters a kind of small holding tank near the hot water heater from which many small lines go out directly to each hot water fixture in the home.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures  

Clean Air Delivery Rate (CADR) is a measurement of effectiveness of portable air cleaners developed by the Association of Home Appliance Manufacturers and is based on measuring the volume, in cubic feet, of filtered air that the filter delivers per minute. 

Coefficient of Performance (COP) is a measure of how efficiently a heating system will operate at a specified outdoor temperature (usually 47 degrees F). The higher the COP, the more efficient the system.

Compact design conventional system refers to a hot water system in which a hot water line runs as a main line (no holding tank, see Central manifold distribution system) from the hot water heater then branches to the fixtures; in most cases, the branches are short and the main hot water line is long. This system, if not designed well, can lead to long waits for hot water the further the fixture is from the hot water heater, and a lot of wasted cold water flows down the drain as the user waits for the hot water.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures

CFL - Compact fluorescent light.

Combined Appliance Efficiency Rating (CAE) is the measure used to measure the efficiency of an integrated space heating and hot water heating system.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures.

Conduction is the transfer of heat though a solid object, moving from warm to cold. Certain substances, like glass and metal, are very good heat conductors while other substances, such as cellulose or materials used to make insulation, are good insulators. The degree to which a particular object resists the conduction of heat is referred to as its R-value, and the higher the R-value the better the resistance/insulation.  See our Article Insulation and the Building Envelope: Controlling Heat Loss and Gain

Convection – refers through the movement of air. Air moves, and this is the reason for warm air leaks and cold air infiltration through cracks, seams and other gaps in the building envelope. Warm air rises upwards to the attic or up the chimney and pulls in cold air through the basement or gaps in windows and doors, etc. on lower floors.   See our Article Insulation and the Building Envelope: Controlling Heat Loss and Gain.

Daylighting refers to the use of windows, skylights and doors to bring daylight into a building which reduces the need for artificial lighting and consequently energy usage. Refer to our Article Window, Skylight and Door Basics -- Increasing Energy Efficiency.  

Department of Energy Inventions and Innovation Program offers financial grants and technical support to inventors and small businesses for developing promising energy-saving concepts and technologies.  Click here for more information.   

Direct Circulation Solar Hot Water System pump the domestic water to be used in the household through the solar heating unit then directly into the home plumbing system for use.  See our Article Water Heating -- Understanding Water-Saving and Energy-Saving Measures

Drain Water Heat Recovery 
is a technology that transfer heat from drain water back to the water heating system in a manner that saves energy.  See our Article  Water Heating -- Understanding Water-Saving and Energy-Saving Measures

Emissivity is the ability of a product to absorb certain types of energy (specifically infrared) and radiate that energy through itself and out of a room. A substance with high emissivity, such as one pane of clear glass, will transfer over 84 percent of the infrared energy from a warm room outside to the cold air. The lower the conductivity and emissivity of the glass, the lower the rate of heat loss and the lower the U-factor. Low emissivity (low-e) coatings on the glass are either a soft or hard coating of microscopically thin, virtually invisible, metal or metallic oxide layer deposited directly on the surface of one or more of the panes of glass, and in addition low-e coatings can be spectrally selective which means they can filter 40%-70% of the heat while still allowing a full amount of visible light to transmit through the pane. For more information see the National Fenestration Rating Council fact sheet.  Also see our Article Window, Skylight and Door Basics -- Increasing Energy Efficiency

Energy Efficiency Ratio (EER) measures how efficiently a cooling system will operate when the outdoor temperature is set at a specified level (usually 95 degrees F). The higher the EER the more efficient the system.

Energy Factor (EF) is a rating given to conventional water heaters by the Gas Appliance Manufacturers Association (GAMA), and is the ratio of delivered energy to input energy.

ENERGY STAR for Homes is a national, voluntary program sponsored and developed by the U.S. Environmental Protection Agency that promotes the construction of energy-efficient homes through the application of a set of comprehensive building standards focused on energy efficiency.

Environmental tobacco smoke (ETS), or Secondhand Smoke is the mixture of smoke that comes from the burning end of a cigarette, pipe, or cigar, and smoke exhaled by the smoker. According to the EPA, it is a complex mixture of over 4,000 compounds, more than 40 of which are known to cause cancer in humans or animals and many of which are strong irritants.  See our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination

Foam Insulation is either open cell or closed cell and is sprayed into walls or cavities.   See our Article Insulation and the Building Envelope -- Controlling Heat Loss and Gain.

Flow Rate is the amount of water, usually measured in gallons per minute, that flows through a given fixture and is particularly relevanta when sizing a tankless hot water heater.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures .

Forest Stewardship Council (FSC-certified) is an international non-profit organization that promotes environmentally appropriate, socially beneficial, and economically viable management of the world's forests.  The FSC sets standards for environmentally responsible forestry and timbering, and provides a certification process for wood and timber products that involve a chain-of-custody proof process which traces the origins of a given piece of wood or wood product all the way back to the seedling.  Click here for more information.

Formaldehyde is a colorless, pungent-smelling gas and is widely in the manufacting of building materials, such as fiberglass insulation, and many household products such as pressed or composite woods. It is also a by-product of combustion and certain other natural processes and can present in substantial concentrations both indoors and outdoors.  See our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination

Gas fills refers to the injection of inert gases such as argon or krypton in between the panes of multi-paned windows to increase energy efficiency.  See our Article Window, Skylight and Door Basics -- Increasing Energy Efficiency.

Gray water is any untreated, used household water, other than from toilets, and typically comes from sinks, dishwashers, tubs and showers, and clothes washers. Click here for for information. 

Green roof or vegetated roof is a roof that is wholly or partially covered with vegetation and soil planted over a waterproof membrane.

Ground-Level Ozone is ozone that exists in the earth’s lower atmosphere, produced by a chemical reaction between nitrogen oxides and VOCs (from car exhaust, industrial pollution, paints and chemical solvents) that come into contact with sunlight, and it is harmful to the environment and human health. Ground-level ozone is the primary constituent of smog.

Hardscapes refers to paved areas like asphalt streets and concrete sidewalks, parking lots, patios etc. where the soil is no longer exposed to the actual surface of the earth and which is impermeable to water.

Heat Exchanger is a piping device, usually made of a highly conductive material such as steel, copper, bronze, stainless steel, aluminum, or cast iron, that moves heat from a liquid, usually a specially heat reactive heat transfer fluid, to another liquid such as water, or between liquid and air.

Heat Island Effect refers to the phenomenon that urban and suburban temperatures are hotter than nearby rural areas, sometimes by as much as 2 to 10°F.  Elevated temperatures can increase cooling loads and consequently increase peak energy demand, air conditioning costs, air pollution levels, and heat-related illness and mortality.

Heat-recovery ventilator (HRV) or an energy-recovery ventilator (ERV). HRVs use heat exchangers to heat or cool incoming fresh air, recapturing 60 to 80 percent of the conditioned temperatures that would otherwise be lost and making your heating system work less hard to heat the warmer incoming air, or conversely in the summer they cool the incoming hot air thereby reducing the cooling load. Energy Recovery Ventilators (ERVs) exchange moisture between the two air streams, typically from the incoming humid air in the summer to the exhaust stream but they cannot be relied upon for total dehumidification needs.  See our Article Ventilation - Designing an Effective and Energy Efficient Ventilation Plan

Heat Transfer fluids in a solar hot water system are highly thermo-reactive fluids that flow through pipes in the solar heat collector plates absorbing heat, after which the super-hot fluid flows through a heat exchanger where it transfers its heat through conduction to the domestic hot water. There are many types of fluids that may be used for this purpose and your choice depends on your climate zone and the degree to which you need to guard against freezing. The following chemical criteria must be considered:
• Coefficient of expansion – the change in length or volume due to a specified change in temperature
• Viscosity – the resistance of a liquid to flow
• Thermal capacity – the ability of the fluid to store heat
• Freezing point – the temperature below which it turns into a solid
• Boiling point – the temperature at which it boils
• Flash point – the lowest temperature at which the vapor above a liquid can be ignited in air.
In a cold climate like NYC, choose a fluid with a low freezing point. Viscosity and thermal capacity affect the amount of pumping energy required – for example a fluid with low viscosity takes less energy to pump. Also consider the fluid’s corrosiveness and stability when subjected to heat and cold. Refer to the DOE Consumer’s Guide to Heat-Transfer Fluids for Solar Water Heating Systems for a summary of the attributes of the most commonly used heat transfer fluids -- air, water, glycol/water mixtures (anti-freeze, highly toxic), hydrocarbon oils, refrigerants and silicones.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures

Heating Season Performance Factor (HSPF) is a measurement of the efficiency of a heating system and is calculated by taking the total annual heating requirements divided by the total electric power used to run the system.

HVAC – heating, ventilating and air conditioning

Home Energy Rating System (HERS) Index is a scoring system established by the Residential Energy Services Network (RESNET) in which a home built to the specifications of the HERS Reference Home (based on the 2006 International Energy Conservation Code) scores a HERS Index of 100, while a net zero energy home scores a HERS Index of 0. The lower a home’s HERS Index, the more energy efficient it is in comparison to the HERS Reference Home.

Each 1-point decrease in the HERS Index corresponds to a 1% reduction in energy consumption compared to the HERS Reference Home. Thus a home with a HERS Index of 85 is 15% more energy efficient than the HERS Reference Home and a home with a HERS Index of 80 is 20% more energy efficient.

The System involves an analysis of a home's construction plans and on-site inspections, and it is an integral part of the Energy Star for Homes ProgramClick here for more information on HERS. 

Hot Water Recirculation System is an energy savings technology applied to the dometic hot water delivery system to reduce or eliminate cooling of water in the hot water feed lines with consequential energy savings.   See our Article Water Heating -- Understanding Water-Saving and Energy-Saving Measures.

Hydro-Air refers to a heating and cooling system that uses an air handler to heaet and cool air by passing it through a heat exchanger composed of a coil with hot water or chilled water running through it.  The heated or cooled air is subsequently blown into the house's air duct system.  See our Article Water Heating -- Understanding Water-Saving and Energy-Saving Measures.

Indirect Circulation Solar Hot Water System pumps a non-freezing heat transfer fluid or air through a heat exchanger which transfers heat to the the domestic water supply.  See our Article Water Heating -- Understanding Water-Saving and Energy-Saving Measures.

International Energy Conservation Code® The IECC® is a model energy building code produced by the International Code Council® (ICC®), a US non-government to establish minimum design and construction requirements for energy efficiency. The code contains minimum energy efficiency provisions for residential and commercial buildings, offering both prescriptive- and performance-based approaches. The code also contains building envelope requirements for thermal performance and air leakage. According to the International Code Council, the intent of the IECC is to establish an energy conservation code that conserves energy, minimizes increase in construction costs, allows for new materials and methods, and eliminates preferential treatment for particular industries or types or classes of materials, products or methods of construction.

LEED® for Homes is a voluntary “green” building project certification program developed by US Green Building Council to promote the transformation of the home building industry towards more sustainable practices. LEED” stands for The Leadership in Energy and Environmental Design. “LEED®” is a registered trademark of the U.S. Green Building Council.  See our Article Navigating Green Building Guidelines Part I: A LEED® for Homes Guidelines Primer – The Lay Person’s Guide

LEED® for Neighborhood Development is a rating system developed by the USGBC, Congress for the New Urbanism (CNU) and the Natural Resources Defense Council (NRDC), with a goal to promote neighborhood design projects that successfully protect and enhance the overall health, natural environment, and quality of life in communities by implementing such characteristics as reducing vehicular mileage by having jobs and community resources in walking distance, public transportation and effective water conservation measures.

Lite refers to a pane of glass surrounded by structural framing.

Low-e (low emissivity) coatings – see Emissivity

MERV or Minimum Efficiency Reporting Value MERV refers to the rating measurement scale developed by ASHRAE to determine how effective a filter is at removing particles of a certain size -- the higher the rating the better the filter is at removing particles. A rating of 8 or above means that the filter will remove 20-35% of particles that are 3 to 10 microns in size (mold spores, for example vary from 4 to 40 microns, most being less than 10). By comparison, MERV 14 filters are typically the filter of choice for critical areas of hospitals (to prevent transfer of bacteria and infectious diseases).  Also see our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination

Modified Energy Factor (MEF) is a new equation that replaced Energy Factor as a way to compare the relative efficiency of different units of clothes washers. The higher the Modified Energy Factor, the more efficient the clothes washer is.

Mullioned divided lites – panes of glass in a window that are separated by vertical structural framing.  See our Article Window, Skylight and Door Basics -- Increasing Energy Efficiency

Mortgage Industry National Home Energy Rating Standards. The standards set the national procedures for home energy ratings. Click here to view the standards.
 
Ozone (O3) is a gas composed of three oxygen atoms and occurs naturally in the earth’s atmosphere 10-30 miles above the earth surface and protects life on earth from harmful sun rays. See also Ground Level Ozone.

Perm Rating refers to the "vapor permeance value" given to vapor barriers used with insulation, and a measure the degree to which a material  resists the penetration of moisture.  Vapor barriers should have a perm rating of 1.0 or lower.  See our Article Insulation and the Building Envelope -- Controlling Heat Loss and Gain.

Radiation -- electromagnetic waves traveling through space, such as from the sun or a radiator, and one of the forms of heat transfer/loss. See our Article Insulation and the Building Envelope: Controlling Heat Loss and Gain.


Radon (Rn) is a colorless, odorless, radioactive gas. Radon is most commonly produced by the breakdown of uranium in the soil or rock on which homes are built.  Also see our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination

Rain water harvesting refers to the gathering, or accumulating and storing, of rainwater for use as drinking water, domestic water, livestock and irrigation. Click here for more information. 

Replacement window is a complete new window unit, including frame, that is designed to be installed inside the frame of your existing window. Due to the additional framing material the amount of glass is reduced. See also sash replacement kits.  See our Article Window, Skylight and Door Basics -- Increasing Energy Efficiency.


Rocky Mountain Institute (RMI) is a nonprofit organization was established in 1982 and focuses on a broad base of issues for a the advancement of products, design and related disciplines to achieve natural resource efficiencies, sustainability and conservation. 

R-value is a measure of conductivity and measures resistance to heat loss.

Sash replacement kits for double hung windows work by replacing the operable part of the window while using the existing window frame and tracks, assuming they are in good condition. The new windows can be more energy efficient if they make a tight seal and add multiple panes and other features like low-e coatings and gas fills. They can be similarly prices to replacement windows but can save labor costs because they can be easily installed by the homeowner, and they reduce construction waste. See also replacement windows.  See our Article Window, Skylight and Door Basics -- Increasing Energy Efficiency.

Seasonal Energy Efficiency Ratio (SEER) is the unit of measurement of the efficiency of air conditionting systems developed by the Air-Conditioning and Refrigeration Institute. Generally, the higher the SEER, the less electricity the system needs to function.

Sheathing is a layer of plywood, fiber-board, pressed-board or other material, applied to the outer studs, joists, and rafters of a building to strengthen the structure and serve as a base for an exterior weatherproof cladding. It covers the exterior of a house’s frame.

Solar Energy Factor (SEF) is a measurement used to rate the efficiency of a solar hot water heating system, along with the Solar Fraction. The solar energy factor is defined as the energy delivered by the system divided by the electrical or gas energy put into the system. The higher the number, the more energy efficient the system. Solar energy factors range from 1.0 to 11, and systems with ratings of 2 or 3 are the most common.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures

Solar Fraction (SF) is a measurement used to rate the efficiency of a solar hot water heating system, along with the Solar Energy Factor (SEF). The SF calculation involves the comparison of the SEF and EF, however, in the marketplace the term is used to refer to two different calculations, one of which renders a result that describes the portion of the total conventional hot water heating load (delivered energy and tank standby losses) provided by solar energy (this is the definition and calculation used by the SRCC). The alternate definition/calculation yields a result that states the portion of the total water heating load (losses are NOT included) provided by solar energy, and this alternate method of calculating solar fraction will yield higher solar fractions.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures

Solar Heat Collector Plates are either flat plate panels or evacuated tubes used to absorb heat from the sun in a solar hot water system.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures

Solar Heat Gain Coefficient (SHGC) measures how well a window blocks heat from sunlight. SHGC is expressed as a number between 0 and 1. The lower a window's solar heat gain coefficient, the less solar heat it transmits. See our Article Window, Skylight and Door Basics -- Increasing Energy Efficiency

Solar Rating and Certification Corporation (SRCC) is a non-profit organization that tests and rates the performance and efficiency of solar thermal (water heataing) equipment. See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures.

Structural Insulating Panels (SIP) are rigid panels often made of a foam-board core sheathed on one or both sides with plywood or wall board to be used structurally as pre-insulated walls or as insulation to be retrofitted and installed on top of an existing roof.  See our Article Insulation and the Building Envelope -- Controlling Heat Loss and Gain.

Spectrally selective —Heat-Absorbing, tinted window glazing contains special tints that change the color of the glass and are able to absorb a large fraction of the incoming solar radiation through a window, thus reducing the SHGC, visible transmittance and glare. See also Emissivity. See our Article Window, Skylight and Door Basics -- Increasing Energy Efficiency.

Structured plumbing system is based upon the recirculation of hot water.  See our Article Water Heating - Understanding Water-Saving and Energy-Saving Measures.

A thermal barrier restricts or slows the flow of heat using materials that do not conduct heat or conduct it poorly, such as fiberglass, rock wool, cellulose, vermiculite, spray foam and rigid board insulation. This resistance to heat flow is measured by the R-value of the material. Because insulation can do a poor job stopping air flow due to the difficulty in plugging every hole and sealing every gap and joint, a separate air barrier or skin is needed on all six sides to stop the flow of air. 

A thermal break is an element of low heat conductivity placed between the low insulating and heat-conductive elements that would otherwise be in contact, in order to reduce or prevent the flow of heat between them.

A thermal bridge is created when materials that are poor insulators come into contact, allowing heat to flow through the path created. For example, a wooden stud conducts heat more than the insulation placed between the studs and therefore the studs function like a bridge through which heat can pass through the wall resulting in heat loss or gain. It is therefore not adequate to simply insulate around the bridge, the bridge must be eliminated by using a thermal break or materials with better insulating properties.

U-Factor or U-value measures the rate of heat transfer and refers to how well a window prevents heat loss (the opposite R-value which refers to insulating value.) The values are usually between .20 and 1.20, and the lower the U-value the lower the amount of heat that transfers and therefore the greater a window's insulating value. U-factor, on the other hand, takes into account more than conductivity. It also is affected by the airflow around the window and the emissivity of the glass. See our Article  Window, Skylight and Door Basics -- Increasing Energy Efficiency

Vapor barrier is a moisture resistant layer between the conditioned space -- the indoor space to be heated or cooled --and the insulation which prevents insulation from becoming moist . See our Article Insulation and the Building Envelope -- Controlling Heat Loss and Gain. 

Vapor Permeance Value see "Perm Rating" above.

VOC (volatile organic compounds) Also referred to as “organic gases”, include those chemicals emitted as gases from certain solids or liquids. According to the EPA, VOC concentrations can be 10 times higher indoors than outdoors regardless of whether the location is urban or rural. Exposure can cause respiratory, skin and eye irritation; headaches; nausea; muscle weakness; fatigue; dizziness; memory loss; and more serious ailments and diseases including asthma, cancer, and damage to the liver, kidney and central nervous system.  see our Article Indoor Air Quality -- Identifying Sources and Making Renovation Choices that Eliminate Contamination
Xeriscaping refers to the landscaping practice of using drought resistant plants, or plants that do not require supplemental irrigation, and taking measures to reduce water loss though evaporation.

The Water Factor is the number of gallons per cycle per cubic foot that the clothes washer uses. The lower the water factor, the more efficient the washer is. So, if a clothes washer uses 30 gallons per cycle and has a tub volume of 3.0 cubic feet, then the water factor is 10.0.