Active system
Traditional heating, cooling and ventilating systems which use
mechanical means to artificially condition (cool, heat, ventilate) the
air supply in buildings, and draw power for these mechanical processes
from electricity or gas.
Adaptable buildings
Buildings that can be
easily remarketed, retrofitted, or reconfigured to better meet the
changing needs of occupants, maintenance crews, and the larger
community.
Agricultural by-products
Products developed in
agriculture that are not the primary goal of the agricultural activity.
Some of these are being used as building materials.
Alternative fuel vehicle (AFV)
A vehicle powered by a fuel other than gasoline.
Air changes per hour (ACH)
The air outside a
building is constantly infiltrating through cracks in a building shell
and exchanging with inside air. ACH is the measure of the rate at which
this occurs. For example, an ACH or 0.5 means that all the air in the
building will change out in two hours.
Air infiltration
Uncontrolled inward air
leakage through cracks in a building envelope. May also refer to air
leaking outward (also called air exfiltration).
Air retarder/air barrier
A material installed
around a building frame to prevent or reduce the infiltration of air
into the interior. Installed as an energy-efficiency measure to keep
out air, which may be too hot, cold or moist for comfort. Not to be
confused with a vapour retarder/ vapour barrier.
Albedo
Ratio of reflected light to the total
amount of light falling on a surface. In hot climates, it is desirable
to use roofing materials with a high albedo.
Annual fuel utilisation efficiency
The ratio of annual output energy to annual input energy. Measure of
efficiency of gas furnaces and boilers.
Appraisal value
An estimate of the value of property substantiated by various analyses,
usually by comparison with similar properties.
Attic venting system
Venting devices installed
in an attic structure which allow fresh outside air to enter the attic
and exhaust out of it, so the attic will be cooler and drier. The most
effective attic venting system combines a continuous soffit vent with a
continuous ridge vent. This system allows the most even flow of air
over the underside of the roof, and the best position for the exhaust
vent at the highest point of the attic where the attic air is hottest.
Autoclaved cellular concrete
Mix of lime,
sand, cement and water are mixed, and then put into moulds, where an
aluminium powder is added, which causes the mass to expand. It is then
put into a steam-curing chamber (autoclaver), which gives it great
strength. The resulting material has many benefits (non-combustible,
easily worked, R-value of 1.25 per inch, etc).
Backdrafting
The occurrence of combustion
gases from a gas appliance entering the living space instead of being
drawn up the vent pipe and exiting a building. This may happen as a
result of depressurization (for example, when the furnace or exhaust
fans are turned on).
Backflow preventer
An anti-siphoning device on
a water pipe to prevent water/liquid (which might be contaminated) from
backing up into the water system. For example, the end of a garden hose
lying in a flower bed could become contaminated by pesticide and back
into the fresh water supply, if no backflow preventer were installed.
Frequently required by building codes.
Balance point
The outdoor temperature at which
a building’s heat loss to the environment is equal to internal heat
gains from people, lights, and equipment. Surface load dominated
buildings such as single family detached residences will have balance
points in the 55-65 degree Fahrenheit range. Internally load dominated
structures, like office buildings, may have balance points so low that
the climate never overcomes their internal heat gain.
Ballast
A device used to provide the starting
voltage or to stabilise the current in a circuit (as of a fluorescent
lamp). May be magnetic or electronic.
Biological wastewater management
Purifying
wastewater in a natural or emulated wetland environment. Such systems
are powered mainly by sunlight and achieve purification through the
combined action of living food chains, many of which are microscopic.
Biomass
Plants and plant materials, trees, crop residues, wood and bark
residues, and animal manure.
Biomass energy
The energy released from biomass when it is eaten, burned, or otherwise
used as or converted into fuel.
Blackwater
Water from toilets, kitchen sink,
or other dirty sources (e.g. washing machines used for diapers), which
may be contaminated with micro organisms or harmful bacteria.
Borate-treated wood
Treatment of wood with
borates to make it resistant to termites and moisture. Borate is a
mineral product derived from borax and is benign compared with most
other wood treatments.
Brownfields
Abandoned, idled, or under-used
industrial and commercial facilities/sites where expansion or
redevelopment is complicated by real or perceived environmental
contamination.
British Thermal Unit (BTU)
A measure of heat
energy. Approximately the heat required to raise the temperature of a
pound of water one degree. About equal to the energy released by the
lighting of one match.
Building codes
Municipal ordinances that regulate the construction and occupancy of
buildings for health and safety reasons.
Building ecology
Physical environment and
systems found inside the building. Key issues include air quality,
acoustics, and electromagnetic fields.
Building envelope
Building elements (e.g.
walls, roofs, floors, windows, etc) that enclose conditioned spaces and
through which energy may be transferred to and from the exterior.
Built environment
All human-built structures (as opposed to the natural environment).
Caliche
A type of soil containing calcium carbonate that makes a very hard
brick/block without firing and is a common roadbed material.
Carbon dioxide (CO2)
A heavy, colourless gas
that does not support combustion. Made of one carbon atom and two
oxygen atoms, it is formed especially in animal respiration and in the
decay or combustion of animal and vegetable matter. It is absorbed from
the air by plants in photosynthesis, and is an atmospheric greenhouse
gas.
Carbon monoxide (CO)
A colourless, odourless,
very toxic gas made up of carbon and oxygen that burns to carbon
dioxide with a blue flame and is formed as a product of the incomplete
combustion of carbon.
Carrying capacity
The amount of demand or
usage for a particular resource that can be sustained without depletion
or degradation of dependent life forms.
Cellulose
The fibrous part of plants used in making paper and textiles, which may
be made into building products, such as insulation.
Cementitious
Having the properties of cement. Cement is the primary binding agent in
concrete.
Certified sustainably managed forest
Forest
harvesting practices that have been certified as sustainable by a
qualified entity. The underlying guideline is preservation of a diverse
forest that exhibits the same ecological characteristics as a healthy
natural forest.
Change order
A form used by an architect or contractor to specify changes from the
approved original plan.
Charrette
An intensive design process which
involves the collaboration of all project stakeholders at the beginning
of a project to develop a comprehensive plan or design. Although it may
only take place over a few short days, it establishes groundwork for
communication and a team-oriented approach to be carried throughout the
building process.
Chlorofluorocarbons (CFCs)
Any of a group of
compounds that contain carbon, chlorine, fluorine, and sometimes
hydrogen and have been used as refrigerants, cleaning solvents, aerosol
propellants, and in the manufacture of plastic foams. CFCs have been
linked to the destruction of the ozone layer and their use is being
phased out because they destroy the planet's stratospheric ozone
protection layer.
Cistern
A tank to hold a supply of fresh water, typically rainwater. May be
above or below ground.
Colour rendering index of light (CRI)
Colour
objects will appear when illuminated by a given electric light. On a
scale from 1 to 100, the higher a number, the more an object will look
the colour it actually is when illuminated by an electric light.
Colour temperature of light
Colour appearance
of a light. So called "warm" looking lights are actually cooler than
"cool" looking lights. An incandescent light has a colour temperature
of about 2500; a cool white fluorescent light has a colour temperature
of about 4000.
Combustion gases
The gases, such as carbon
monoxide, that result from the process of burning. In a building, these
are produced by gas appliances, such as furnaces and water heaters.
Proper venting must be assured.
Commissioning
The process of ensuring,
verifying, and documenting that new equipment and systems are installed
and able to operate according to the design intent.
Community
(Biological definition) An
association of organisms of different species living together in a
defined habitat with some degree of mutual interdependence.
Compact fluorescent lighting
A fluorescent lamp/bulb that is compacted to fit into an Edison light
socket.
Comparable property (comps)
Another property
to which a subject property can be compared to reach an estimate of
market value. Typically as much like the subject property as possible
in age, quality, location, etc.
Composting
A waste management option involving
the controlled biological decomposition of organic materials into a
relatively stable humus-like product that can be handled, stored, and
applied to the land without adversely affecting the environment.
Composting toilet
A toilet which uses little or no water in which the waste composts to a
material which can be safely used as a soil amendment.
Condensation
Deposit of water vapour from air
on a cold surface whose temperature is below the dew point. For example
a cold window glass exposed to warm humid air.
Condensation resistance factor (CRF)
Indication of a window's ability to resist condensation. The higher the
CRF, the less likely condensation is to occur.
Conduction
Flow of heat through solid materials which are touching each other.
Conductor
A substance or body capable of transmitting electricity, heat, or
sound.
Constructed wetland
Any of a variety of
designed systems that are modelled after natural wetlands, use aquatic
plants, and can be used to treat wastewater or runoff.
Convection
Transfer of heat by means of a moving stream of air or water.
Cooling/heating load
A building's demand for heat/cool to offset a deficit/overage of the
opposite.
Covenants
Promises written into deeds and
other instruments agreeing to performance or non-performance of certain
acts, or requiring or preventing certain uses of the property.
Cross ventilation
Passive building strategy to
cool a building using outdoor breezes. Requires proper placement and
sizing of doors, operable windows and walls to promote air movement
through the building.
Culvert
A sewer or drain running under a road or embankment.
Day lighting
The use of controlled natural lighting methods indoors through
skylights, windows, and reflected light.
Degree days
The difference between the average
daily temperature and 65 degrees Fahrenheit, used as a baseline. This
measure is used to estimate building energy needs. It is also a quick
way to compare the severity and character of a climate. A heating
degree day is counted for each degree below 65 degrees reached by the
average daily outside temperatures. For example, if, on a given day,
the daily average temperature outdoors is 30 degrees, then there are 35
degrees below the 65 degrees. Thus, there are 35 heating degree days
for that day. Areas with more than 5500 HDDs per year are characterised
by long cold winters. Areas with less than 2000 HDDs per year are
characterised by very mild winters. Reverse this process (degrees above
65 degrees) to calculate Cooling Degree Days. Areas with more than 1500
Cooling Degree Days (CDDs) are characterised by long hot summers and
substantial cooling requirements. Areas with less than 500 CDDs per
year are characterised by mild summers and little need for mechanical
cooling.
Design conditions
The exterior and interior
environmental parameters specified for air conditioning (heating,
cooling, ventilation) and electrical design for a building.
Design temperatures
Temperatures used for
modelling energy calculations. They are established for winter and
summer for specific cities, representing the calculated low and high
extremes.
Dessicant
A drying agent, such as silica gel, which can be used to reduce latent
cooling loads.
Dew point
The temperature at which water vapour in air will condense at a given
state of humidity and pressure.
Dirunal flux
The difference between daytime
and night-time temperatures. A diurnal flux of 25 degrees Fahrenheit or
above indicates an arid climate suitable for mass building
construction.
Drip irrigation
Above-ground, low-pressure
watering system with flexible tubing that releases small, steady
amounts of water through emitters placed near individual plants.
Dry bulb temperature
The temperature of air indicated by an ordinary thermometer.
Dust spot test
Test of filter efficiency.
Earth sheltering (also earth berming)
Building
below ground level. Soil temperature varies less than air temperature
[deeper soil = more constant temperature]; an earth-sheltered structure
provides an interior climate which is generally closer to comfort level
than a conventional interior space. Savings on heating and cooling
bills are often in the range of 40-60%.
Eave
The portion of a roof that extends beyond the wall. It serves to
protect the wall below from the elements.
Ecology
In biology, it is the study of the
relationship between living organisms and their environment. In
sociology, it is the study of the relationship between the distribution
of human groups with reference to material resources and the consequent
social and cultural patterns.
Ecosystem
A complex set of natural interconnected elements on which a habitat's
survival depends directly or indirectly.
Eco-tourism
Partnerships between the tourism
industry and conservation efforts to preserve natural and cultural
resources in resort destinations.
Edible landscaping
Landscaping containing
vegetation which is cultivated for its ability to be eaten and digested
by humans, for example, fruit trees or grape arbors.
Energy efficiency ratio (EER)
The ratio of net
cooling capacity of an air conditioner in Btu per hour to total rate of
electric input in watts under designated operating conditions.
Efficacy of a light bulb/lamp
Measure of lumens of light per watt.
Efficiency
The ratio of the amount of useful energy output to the energy input for
a given device.
Electricity
A form of energy generated by
friction, induction, or chemical change that is caused by the presence
and motion of elementary charged particles of which matter consists.
Electromagnetic radiation
A series of electromagnetic waves.
Electromagnetic spectrum
The entire range of
wavelengths or frequencies of electromagnetic radiation extending from
gamma rays to the longest radio waves and including visible light.
Electronic ballast
Type of ballast for a fluorescent light which increases efficiency and
reduces flicker and noise.
Embodied energy
All the energy required to
grow, harvest, extract, manufacture, refine, process, package,
transport, install and dispose of a particular product or building
material.
Emissivity
Ability of a material to transfer
far-infrared radiation across an air space. Materials such as aluminium
foil have poor ability to do this (they have a low emissivity rating)
and are therefore useful, when properly spaced next to an air space in
controlling heat in a hot climate. For example, a roof radiant barrier
placed below roof decking over the attic space keeps the attic cooler.
End-of-pipe protection
End-of-pipe protection
refers to added technical installations for environmental control of
emissions. They operate independently from the production process or
are an identifiable part added on to production facilities.
End-use/Least-cost
A decision-making tool that
keeps the planning team focused on the end users' needs. It is a key
component of green design and development because it identifies how to
achieve the greatest benefits at the least cost in financial, social,
and environmental terms.
Energy
The capacity for doing work. Different
types of energy may be transformed from one form to another. English
units express energy in Btu's or kilowatt-hours (kWh).
Energy conservation
Efficiency of energy use,
production, transmission, or distribution that yields a decrease in
energy consumption while providing the same, or higher, levels of
service.
Energy or water efficiency
Using less energy
or water to perform the same tasks. A device is energy-efficient if it
provides comparable or better quality of service while using less
energy than a conventional technology. Building weatherization or
high-efficiency showerheads are efficiency technologies.
Energy recovery ventilator (ERV)
An energy
recovery ventilator (ERV) is an air to air heat exchanger or
preconditioner, designed to reduce the energy required to heat or cool
required outdoor air in mechanical ventilation systems by as much as
80%. These products exchange temperature and moisture properties from
one airstream to another. The result is capturing the cooling or
heating energy from the exhaust air before it leaves the building.
Engineered wood
Reconstituted wood products that result in strength appropriate for a
given use and consistent quality with less material.
Environmentally sound technologies
Environmentally
sound technologies are techniques and technologies capable of reducing
environmental damage through processes and materials that generate
fewer potentially damaging substances, recover such substances from
emissions prior to discharge, or utilise and recycle production
residues. The assessment of these technologies should account for their
interaction with the socioeconomic and cultural conditions under which
they are implemented.
Equity
That portion of an ownership interest
in real property (or other securities) that is owned outright, rather
than financed by debt.
Evaporative cooling
Passive building strategy
employing the evaporation of water directly into hot, dry air streams
to produce cooling; limited to arid climates.
Expanded polystyrene
A rigid insulation
material (also called bead board) made by heating pentanesaturated
polystyrene pellets. Pentane is used instead of the CFC's or HCFC's
used to make extruded polystyrene. CFC's and HCFC's cause damage to the
ozone layer. Frequently has a high recycled content and comes in
various densities for different purposes.
Fenestration
Architectural term for windows and their placement.
Flow
The volume of a substance passing a point per unit time (e.g. meters
per second, gallons per hour, etc).
Flow form features
Water features of a
building that are not only viewed as artistic decorations, but also
maintain a pleasant level of humidity and acoustics as part of the
building ecology.
Fluorescent lamp
A lamp (light bulb) in which
light is produced by passing an electric arc between tungsten cathodes
in a tube filled with a low pressure mercury vapour and other gases.
The arc excites the mercury vapour, which generates radiant energy,
primarily in the ultraviolet range of the electromagnetic spectrum.
This causes the phosphor coating on the inside of the tube to
"fluoresce", converting the ultraviolet into visible light.
Fly ash
Ash residue from high-temperature
combustion processes. Electric power plants using western coal produce
a non-toxic fly ash which can substitute for a portion of Portland
cement in concrete, to produce a strong, durable concrete.
Formaldehyde
A colourless, pungent-smelling
material used as an adhering component of glues in many wood products.
It may cause respiratory problems, chemical sensitivity, and other
health problems.
Fossil fuels
Non-renewable, naturally-occurring
fuels from organic material deposited in the earth. The altered remains
of once-living organisms that are burned to release energy. Examples
are coal, oil, and natural gas.
Geographical Information System (GIS)
Detailed
information on the soils, hydrology, land use patterns, and plant and
animal habitats of sites, plotted on maps or entered in databases and
employed to evaluate appropriate location of buildings and
infrastructure, and to plan landscaping and other land use
considerations.
Glazing
Transparent or translucent coverings
which allow light to enter rooms and solar collectors while providing
weather protection. Window glass and clear plastic films are examples
of glazing.
Graywater/Greywater
Water that has been used
for showering, clothes washing, and faucet uses. Kitchen sink and
toilet water is excluded. This water can be reused in subsurface
irrigation for yards.
Green development
A development approach that
goes beyond conventional development practice, by integrating the
following elements: Environmental responsiveness—Benefiting the
surrounding environment; Resource efficiency—Using resources in the
construction, development, and operations of buildings and/or
communities in ways that are not wasteful; and Sensitivity to existing
culture and community—Fostering community in design, construction, and
operations. Bringing these elements together through the green
development approach provides numerous environmental and economic
benefits by capitalising on the interconnections.
Green wash
To falsely claim a product is environmentally sound. Also known as faux
green.
Greenfields
Undeveloped land.
Greenhouse gas
Any of several dozen
heat-trapping (radiatively active) trace gases in the earth's
atmosphere which absorb infrared radiation. The two major greenhouse
gases are water vapour and carbon dioxide; lesser greenhouse gases
include methane, ozone, CFCs, and nitrogen oxides.
Habitat
The environment in which an organism or biological population usually
lives or grows.
HCFC
Hydrogen chlorofluorocarbon. Considered to be a contributor to ozone
layer destruction. 1/20th as potent as CFC's.
Heat island effect
The rise in ambient
temperature that occurs over large paved areas. Strategic placement of
trees can reduce this effect and reduce energy consumption for cooling
by 15-30%.
Heat pump
A mechanical device used for heating
and cooling which operates by pumping heat from a cooler to a warmer
location. Heat pumps can draw heat from a number of sources, e.g. air
water or earth and are classified as either air-source or water source
units.
Heat recovery ventilator (or Air-to-Air Heat
Exchangers)
Exhaust
fans that warm the incoming air with the heat from the outgoing air,
recovering about 50-70% of the energy. In hot climates the function is
reversed so that the cooler inside air passes by the incoming hot air
and reduces its temperature.
Highest and best use
The conventional
definition is the property use that, at a given time, is deemed likely
to produce the greatest net return in the foreseeable future, whether
or not such use is the current use of the property. Green development
defines it as not just in terms of maximum return on investment, but
also as that use which best reflects long-term social, cultural, and
financial values held by a community.
High-mass construction
Passive building
strategy of constructing buildings of massive, heat-retaining materials
(such as masonry or adobe) to moderate diurnal temperature swings,
especially in arid climates.
Horizontal axis clothes washer
A washing
machine designed to clean without an agitator. It uses much less water
than vertical-axis models, reduces wear and tear on clothes, and result
in drier clothes.
Human comfort zone
A band of dry bulb
temperatures from 67.5 degrees Fahrenheit to about 78 degrees
Fahrenheit and 20% to 80% relative humidity. Within that zone on the
Psychrometric Chart, all weather conditions which occur are said to be
conducive to thermal comfort, assuming occupants are in full shade,
lightly clothed and only moderately active. All climate data that are
plotted at lower dry bulb temperatures (to the left of the comfort
zone) are indicative of time when solar radiation (passive heating)
could be utilised to restore comfort. All hours above 67.5 F require
shading.
Humidistat
Device for measuring relative humidity.
HVAC
Heating, ventilation and air conditioning (cooling) system.
Hydrogen
A non-metallic element that is the
simplest, lightest and most abundant of the elements; it is normally a
colourless, odourless, flammable gas.
Impervious cover
A ground cover that does not
allow water to pass through it to the soil below. Many jurisdictions
have restrictions on the amount of impervious cover allowed on a
building site, in order to reduce stormwater runoff and resulting
non-point source pollution.
Incandescent bulb
An incandescent bulb is the
most common and least energy-efficient lamp. Electricity runs through a
tungsten filament that glows and produces a soft, warm light. Because
so much of the energy used is lost as heat, these are highly
inefficient sources of light. Halogen lamps are a special, more
energy-efficient type of incandescent lamp containing halogen gas to
produce a brighter, whiter light than incandescent.
Indigenous
Existing, growing, or produced naturally in a region.
Indoor air quality (IAQ)
The cleanliness or
health effects of air in a building is affected by the amount of
compounds released into the space by various materials, carbon dioxide
levels, and microbial contaminants. IAQ is heavily influenced by both
choice of building materials (and cleaning procedures) and ventilation
rates.
Infill
Developing on empty lots of land within
an urban area rather than on new undeveloped land outside the city.
Infill development helps prevent urban sprawl and can help with
economic revitalisation.
Infrared radiation
Electromagnetic radiation whose wavelengths lie in the range from 0.75
micrometers to 1000 micrometers.
Insolation
Amount of solar energy reaching a surface per unit of time.
Insulation
A material (e.g. fibreglass, rock
wool, cellulose, straw) which effectively slows down the movement of
heat. Typically installed around a living space (e.g. in the walls and
attic) to improve comfort and reduce heating and cooling bills.
Material having a relatively high resistance to heat flow and used
primarily to retard the flow of heat. Measured by R-value. The higher
the R-value, the more insulating the material.
Integrated design
A holistic process that
considers the many disparate parts of a building project, and examines
the interaction between design, construction, and operations, to
optimise the energy and environmental performance of the project. The
strength of this process is that all relevant issues are considered
simultaneously in order to "solve for pattern" or solve many problems
with one solution. The goal of integrated design is developments that
have the potential to heal damaged environments and become net
producers of energy, healthy food, clean water and air, and healthy
human and biological communities.
Integrated investments
Also called cleaner
technologies. These are new or modified production facilities designed
so that environmental protection is an integral part of the production
process, reducing or eliminating emissions and discharges and thus the
need for end-of-pipe equipment.
Joist
Parallel horizontal structural framing members. Typically floor joists
and ceiling joists.
Joule
The international unit of energy or work
in the meter-kilogram-second (MKS) system. One joule is equal to one
watt per second or 0.737 foot-pounds. Named after James Joule.
Kilowatt (kW)
A unit of power equal to 1,000
watts. It is usually used as a measure of electrical power. On a hot
summer afternoon a home with central air conditioning and other
equipment in use might have a demand of 4 kW each hour.
Kilowatt-hour (kWh)
A measure of energy equal
to the amount of power multiplied by the amount of time the power is
used. It is most often used to describe amounts of electrical energy. A
100-watt light bulb burning for 10 hours uses one kilowatt-hour of
power.
Land stewardship
The act of managing the land and its resources in a sustainable or
restorative manner.
Latent heat
The heat required to change the phase (e.g. a liquid to a gas) of a
material without altering its temperature.
Latent load
Cooling load resulting from
thermal energy released when moisture in the air goes from a vapour to
a liquid state. In hot humid climates, cooling equipment must have
sufficient capacity to handle this load if occupants are to be
comfortable.
Leichtlehm
Straw and clay mixture, moistened
and pressed between forms, which hardens into a strong material.
Typically used for making walls. An old and durable technique (German
for light loam).
Life-cycle assessment
A process to evaluate
all costs of a product or process through its entire existence,
including extracting and processing of raw materials, manufacturing,
transportation, distribution, use, maintenance, recycling, reuse, and
disposal.
Life cycle
The consecutive, interlinked stages
of a product, beginning with raw materials acquisition and manufacture
and continuing with its fabrication, manufacture, construction and use,
and concluding with a variety of recovery, recycling, or waste
management options.
Light
Visually perceived radiant energy (a small part of the electromagnetic
spectrum).
Light construction
Construction of a building
using materials which have low densities (like wood or aerated
concrete). The lower densities of these materials reduce their capacity
to store heat.
Light shelf
A day-lighting strategy that allows
natural light to bounce off a shelf located in a window and onto the
ceiling to bring light deep into a space.
Light-to-solar-gain ratio (LSG)
A measure of
the ability of a glazing to provide light without excessive solar heat
gain. It is the ratio between the visible transmittance of a glazing
and its solar heat gain coefficient.
Linoleum
A durable, natural flooring material (may be used for other purposes,
such as countertops) made primarily of cork.
Locally-sourced materials
Materials obtained
from a defined radius around a project site, helping to support the
local economy and reducing transportation costs and energy.
Louvers
A series of baffles used to shield a
light source from view at certain angles, or to absorb unwanted light,
or to allow selective ventilation.
Low-emissivity windows
Glazing that has
special coatings to permit most of the sun's light radiation to enter
the building, but prevents heat radiation from passing through.
Lumens
Amount of light given off by a light source.
Mass transit
Conveyance of persons or goods
from one place to another on a local public transportation system such
as light rail, bus, or subway.
Methane (CH4)
An odourless, colourless gas,
nearly insoluble in water, which burns with a pale, faintly luminous
flame to produce water and carbon dioxide (or carbon monoxide if oxygen
is deficient).
Microclimate
The small scale climate of a
building site, affected by site geography, site topography, vegetation,
and proximity to bodies of water, etc, which may very slightly from the
prevalent regional climatic conditions.
Mixed-use development
A development in one or
several buildings that combines several revenue producing uses that are
integrated into a comprehensive plan—such as a project with a elements
of housing, retail, and office space.
Native vegetation
A plant whose presence and survival in a specific region is not due to
human intervention or cultivation.
Neotraditional planning
Based on
nineteenth-century American town prototypes, this type of planning
minimises automobile use and encourages a sense of community with a
town centre and open public areas.
Night-time ventilation
Passive building
strategy of flushing building structures with cool, night-time air to
minimise the next day's cooling load: works best in conjunction with
massive building envelopes.
Nitrogen oxides (NOx)
Oxides of nitrogen that are a chief component of air pollution. Mainly
produced by the burning of fossil fuels.
Non-point source pollution
Pollution,
typically of water, that results from many difficult-to-pinpoint and
control sources, rather than one specific source, such as pollution
from a factory.
Non-renewable fuels
Fuels that cannot be easily
made or "renewed". We can use up, or exhaust, non-renewable fuels. Oil,
natural gas, and coal are non-renewable fuels.
Non-renewable resources
Natural resources that
are consumed faster than can be produced. Thus they are limited
resources that could lead to eventual depletion.
Off-gas/out-gas
The emitting of fumes into the
air. Most new paints, carpeting, and many other building materials
typically offgas chemical compounds which are unpleasant to breathe and
may be hazardous to occupant health.
Operating costs
Costs directly related to the
operation, maintenance, repair, and management of a property and the
utilities that service it. Includes insurance, property taxes,
utilities, maintenance, and management expenses.
Organic matter
Materials of animal or vegetable origin.
Orientation
The relation of a building and its
associated fenestration and interior surfaces to compass direction and,
therefore, to the location of the sun. It is usually given in terms of
angular degrees away from south, i.e. a wall facing due southeast has
an orientation of 45 degrees east of south.
Ozone (O3)
A molecule made of three oxygen
atoms instead of the usual two. Ozone is a poisonous gas and an
irritant at the earth's surface, capable of damaging lungs and eyes.
But the ozone layer in the stratosphere shields life on earth from
deadly ultraviolet radiation from space.
Passive building design
Building
configurations which take advantage of a natural, renewable resource
(like sunlight, cooling breezes, etc). Passive design strategies
typically do not involve any moving part or mechanical processes.
Passive cooling
Using passive building
strategies to relieve the cooling load of a building by capitalising on
such things as predictable summer breezes or by shading windows from
direct summer sunlight.
Passive solar systems
Systems that collect,
move, and store heat using natural heat-transfer mechanisms such as
conduction and air convection currents.
Passive solar heating
Using the sun's energy
(in the form of heat) to diminish a building's heating load, usually
through the use of large window areas which permit light penetration
upon some massive material to utilise the material's thermal storage
capacity.
Pedestrian pocket
A simple cluster of housing, retail space, and offices within a
quarter-mile radius of a transit system.
Permaculture
A unique approach to the practice
of sustainable farming, ranching, gardening and living, by designing
constructed ecosystems that serve the needs of human populations
without degrading the natural environment. Permaculture sites integrate
plants, animals, landscapes, structures, and humans into symbiotic
systems while requiring a minimum of materials, energy, and labour to
maintain.
Permeable
Open to passage of fluids/gases.
Important to know permeability of building materials in exterior walls
if moisture problems are to be avoided.
Photosynthesis
The utilisation of light energy to create chemical bonds; the synthesis
of organic compounds from carbon dioxide and water.
Photovoltaics (PVs)
Solid-state cells (typically made from silicon) that directly convert
sunlight into electricity.
Pleated-media filter
Inexpensive, but highly
effective type of HVAC filter due to its great surface area. Able to
give substantial protection to both equipment and indoor air quality.
Power
The rate at which energy is consumed or
produced. It is expressed in watts (W). A 1-watt source supplies energy
at the rate of 1 joule per second. A 100-watt lamp consumes energy at
the rate of 100 joules per second; the human body involved in normal
activity is rated at about 100W, a significant proportion being used to
drive the brain. The sun radiates energy at the rate of about 70
million watts/m2 of its surface; at the equator the Earth receives a
mean annual solar energy flux of around 1,400 watts/m2.
Pressure-treated wood
Wood that is chemically
preserved to prevent moisture decay. The chemicals typically used are
health hazards for workers. Such wood should not be burned because it
produces toxic fumes, and must be treated as a hazardous waste when
disposed of.
Psychrometric chart
A graphical representation
of the thermodynamic properties of moist air. Used to ascertain the
potential effectiveness of passive strategies to maximise human
comfort.
Radiant barrier
A material (typically an
aluminium foil) that is good at blocking the transfer of radiant heat
across a space because it has a low emissivity. In a hot climate it is
often installed in attics under the roof decking to keep the attic
cooler.
Radiant energy
Energy in the form of electromagnetic waves that travels outward in all
directions from its source.
Radiation
Transfer of heat by means of the
straight-line passage of electromagnetic waves through space (including
vacuums) from a warmer object to a cooler one. Sunlight is a form of
radiation.
Radon gas
A radioactive, colourless, odourless
gas that occurs naturally in soil in many areas. When trapped in
buildings, concentrations build up, and can cause health hazards.
Rafter
Structural roof member that holds up roof decking and roofing.
Raised-heel truss
Roof truss constructed so
the top member (rafter) is raised above the top of the wall instead of
resting on it. Constructed this way to allow space for both attic
insulation and an air path from the soffit vent into the attic.
Rammed earth
A wall-building technique, by
which a certain mixture of earth, water, and usually a small amount of
cement, is very forcibly tamped inside formwork. The resulting wall has
high mass, so it works well in hot climates. It often needs no exterior
or interior covering, thus saving materials.
Recycled material
Material that would
otherwise be destined for disposal but is diverted or separated from
the waste stream, reintroduced as material feed-stock, and processed
into marketed end-products.
Refrigerant
A volatile substance that can be used as a working (cooling) fluid in a
cooling system.
Relative humidity
The percentage of water
vapour in the air in relation to the amount of water vapour the air
could hold at that given temperature before condensing to liquid form.
Renewable energy
Energy produced from
regenerative or virtually inexhaustible resources such as biomass,
solar radiation, the wind, water, or heat from the Earth's interior.
Renewable resources
Resources that are created
or produced at least as fast as they are consumed, so that nothing is
depleted. If properly managed, renewable energy resources (e.g. solar,
hydro, wind power, biomass, and geothermal) should last as long as the
sun shines, rivers flow, wind blows, and plants grow.
Renovation
The process of upgrading an
existing building. Usually there is an attempt to keep the same general
appearance of the building with new materials or to return the building
to its original appearance.
Resistance
The ability of all conductors of
electricity to resist the flow of current, turning some of it into
heat. Resistance depends on the cross section of the conductor (the
smaller the cross section, the greater the resistance) and its
temperature (the hotter the cross section, the greater the resistance).
Restoration
The process of bringing back a structure or landscape to its original
state.
Retrofit
The replacement, upgrade, or improvement of a piece of equipment or
structure in an existing building or facility.
Ridge
The peak of a pitched/sloped roof.
Run-off
Water from rainfall or irrigation that
flows off of land, instead of soaking in. It effectively becomes a lost
resource, and contributes to non-point source pollution.
R-value
A unit of thermal resistance used for
comparing insulating values of different materials; the higher the
R-value of a material, the greater its insulating properties.
Sealant
An adhesive agent used to close or secure something in order to prevent
seepage of moisture or air.
Seasonal energy efficiency ratio (SEER)
The
total cooling output of an air conditioner during its normal annual
usage period for cooling, in Btu/h, divided by the total electric
energy input during the same period, in watt-hours, i.e. the measure of
the energy efficiency of the air conditioner.
Sensible heat
Heat that raises the temperature of a material without changing its
phase.
Sensible load
Heating or cooling load required to meet air temperature requirement
for comfort.
Shading coefficient (SC)
The ratio of solar heat gain through a given window glazing or screen
material to that through 1/8 inch clear double strength glass.
Expressed as a number between 0 and 1. This term is being replaced by
solar heat gain coefficient (SHGC), a more descriptive term. The lower
a window's or screen's SC, the less solar heat it transmits, and the
greater its shading ability.
Sick building syndrome (SBS)
This sickness is
characterised by the symptoms that people have in an unhealthy building
- dizziness, headaches, irritated eyes, nausea, throat irritation and
coughing - these reactions typically cease when the person leaves the
building.
Site assessment
The thorough environmental
analysis conducted as a stage in planning to assess a variety of
measures from soils, topography, hydrology, environmental amenities
such as wetlands, wind direction, solar orientation, animal and plant
habitat, connections to community, etc.
Site development costs
All costs needed to
prepare the land for building construction, such as the demolition of
existing structures, site preparation, off-site improvements, and
on-site improvements.
Sludge
The sediment extracted from wastewater.
Soffit
The enclosed underside of an eave. Some eaves are not enclosed and have
exposed rafter tails.
Solar access
Access to the sun's rays by, for
instance, restricting the location of shade trees or laying out the
building so as to maximise the usefulness of solar energy.
Solar collector
Device which uses the sun's
energy to perform some kind of mechanical advantage which would
normally be supplied by a non-renewable energy source. Photovoltaic
panels (PV) which convert the sun's energy directly into electricity,
and solar hot water panels, which heat pre-heat water before sending it
into a hot water heater are two examples.
Solar energy
Energy received from the sun in
the form of electromagnetic radiation in the wavelength region from 0.3
to 2.7 microns. This includes all visible light as well as some
ultraviolet and infrared radiation.
Solar heat gain coefficient
The fraction of
solar radiation admitted through a window or screen, both directly
transmitted and absorbed, and subsequently released into the living
space.
Solar radiation
Radiant energy received from the sun, from both direct exposure and
diffuse or reflected sunlight.
Source reduction
Elimination of waste at the beginning of a process. Sometimes called
"precycling".
Spectrally-selective glazing
Coated or tinted glazing with optical properties that are transparent
to some wavelengths of energy and reflective to others.
Sprawl
The spread of residential areas, shopping centres, and small industries
outside of city boundaries.
Stakeholder
Those people who are or will be
affected by a real estate development, either financially, i.e.
investors and lenders, or physically, i.e. occupants and users, local
community, local government, and other institutions.
Stretch ratio
In mortgage calculations, the
percentage that lenders will "stretch" a mortgage (i.e. from 28% of the
homebuyer's salary to 30%) for homes that meet energy-efficiency
ratings or other standards, realising that other expenses such as
operating or transportation costs will be lower.
Structural insulated panels (SIPS)
A type of
building system combining exterior sheathing, structural support, and
insulation, and interior sheathing into one modular factory-assembled
unit, thus reducing the number of vertical joints, interior voids, and
assembly time.
Stud
Vertical wall framing members. Typically made of wood or metal.
Sulphur dioxide
A colourless, irritating gas that is a primary cause of acid rain. It
is a by-product of coal combustion.
Super windows
Double or triple-glazed window
sandwiches which contain a centre sheet of coated mylar
"low-emissivity" film and are filled with argon or krypton gas. This
construction and the coating on the film allows short-wave radiation
(visible light) to pass through, but reflects long wavelength radiation
(infrared or heat) so heat cannot pass through. R-values of 4.5 or more
are achieved.
Sustainably-sourced materials
Materials that are acquired in an environmentally sound manner
emphasising efficient and appropriate use of natural resources.
Task lighting
Lighting to provide illumination for a specific activity in a specific
place.
Thermal break
An element of low conductance
placed between elements of higher conductance to reduce the flow of
heat. For example, a thermal break material, such as plastic, may be
placed between the inner and outer parts of an aluminium window frame
to make the window more energy efficient.
Thermal bridging
An element in a building
envelope which has high conductivity (is a poor insulator) and
compromises the insulating value of the envelope; for example, a metal
stud without exterior insulation.
Thermal chimney
A section of a building where
solar heat or thermal currents are controlled and utilised to stimulate
an updraft and exhaust hot air. This draws in fresh air through open
windows or vents and is a passive cooling technique.
Thermal conductance
Ability of a material to
allow heat to pass through it. Aluminium has high thermal conductance,
insulation has low thermal conductance.
Thermal mass
Materials that have a high
capacity for absorbing heat, and change temperature slowly. These
materials are used to absorb and retain solar energy during the daytime
for release at night or during cloudy periods. They include water,
rocks, masonry, and earth.
Thermal storage capacity
The capacity for a building material to store heat internally from the
sun, generally for later use or release.
Tipping fees
Fees charged for dumping large quantities of trash into a land fill.
Topography
The physical features, including the configuration of a surface, of a
place or region.
Transit-oriented development
A mixed-use
community within an average 2,000-foot walking distance of a transit
stop and core commercial area that mixes residential, retail, office,
open space, and public uses in a way that makes it convenient for
residents and employees to travel by transit, foot, bike, etc.
Truth window (or wall)
An exposed section of a wall or window that reveals the layered
components within it.
U-value/U-factor
Measure of the rate of
non-solar heat loss or gain through a material. The reciprocal of
R-value. The lower the U-value, the greater the material's resistance
to heat flow and better its insulating value (the opposite of R-value).
Ultra violet radiation
Electromagnetic
radiation, usually from the sun, that consists of wavelengths in the
range of 4 to 400 nanometers; shorter than the violet end of the
visible spectrum. UV radiation is a health hazard that can lead to skin
cancer or cataracts.
Urban growth boundary
A boundary which
identifies urban and urbanizable lands needed during a specified
planning period to be planned and serviced to support urban development
densities, and which separates these lands from rural lands.
Vapour retarder/vapour barrier
A material
which prevents or drastically reduces the passage of water in vapour
form. Building materials are rated by permeance—their ability to let
water vapour pass through them. Whether or not it is desirable to
install a vapour retarder material on an exterior wall and where to
place depends on the climate where a building is located. In cold
climates, vapour retarders are typically installed on the inside of the
wall frame. In hot humid climates, they are installed on the outside,
or preferably omitted entirely.
Variance
A special permission granted to vary a physical structure or use a
property in a way normally prohibited by existing zoning.
Vernacular
In architecture, vernacular
buildings are seen as the opposite of whatever is academic, or high
style. The traditional architecture of a region. Often times,
traditional architecture is a result of response to the regional
climate and land conditions.
Volatile organic compound (VOC)
A class of
chemical compounds that can cause nausea, tremors, headaches, and, some
doctors believe, longer-lasting harm. VOCs can be emitted by oil-based
paints, solvent-based finishes, and other products on/in construction
materials.
Warm-edge technology
Use of low-conductance spacers to reduce heat transfer near the edge of
insulated glazing.
Wavelength
The distance between two similar
points of a given wave. Wavelengths of light are measured in nanometers
(1 nm = 1 billionth of a meter).
Wetland
Land that is transitional between
aquatic and terrestrial ecosystems and is covered with water for at
least part of the year. These lands are important as buffer zones to
help control flooding and also provide an ecosystem for many diverse
species.
Whole-house fan
A fan typically centrally
located in the ceiling of a house that draws fresh outside air into the
living space, flushes hot air up to the attic and exhausts it to the
outside. Windows must be open and adequate venting area must be present
in the attic. Inexpensive way to cool a house when outside air is
cooler than inside air, and not excessively humid. Must be well sealed
and insulated during cold weather.
Wing wall
Outside walls attached
perpendicularly to exterior walls properly placed near windows to
direct air into the windows for ventilation purposes. A negative
pressure zone is created by the wing wall which stimulates air
movement.
Xeriscaping
Creative landscaping design for conserving water that uses
drought-resistant or drought-tolerant plants.
Zoning
A legal mechanism for local governments
to prevent conflicting land use and promote orderly development by
regulating the use of privately owned land through enforcement.