ARE 5.0 - PPD
Packaged Terminal Unit (Through-The-Wall Units)
+A local system. Mounted on the exterior wall of each room. Within each units, an electric-powered compressor and evaporator coil provide cooling capability. Heating is supplied either by electric resistance coils or by utilizing the compressor in reversible cycle as a heat pump. +Alternative Types of Equipment -Packaged Terminal Units or Terminal Air conditioner, that fit beneath a window; they are connected to outdoor air with a wall box and an outdoor grilled. Through-The-Wall units are contained in a rect. metal box that is mounted directly in an opening in the exterior wall. Also, the familiar Window-Mounted Unit. +Types of Applications: -These units are suitable for apartments, dorms, motels, hotels, office buildings, schools, and nursing homes. +Advantages: -Readily avail and easy to install. Initial cost are often lower than central systems. Each individual room has control of temp. No building space is utilized for equipment and components. Operating cost may be lower. +Disadvantages: -Maintenance costs are high, and equip life is relatively short. Often noisy and inefficient. Air distribution is uneven. Wintertime humidification is not possible. Operating costs are high in areas with very cold winters and costly electricity. Ugly. +Common Building Types: -Apartments, Hotels, Motels, Dorms, Nursing Homes
Active Chilled Beams
+Air and water system. Air discharging from the duct draws a larger volume of room air (secondary air) through the device, where it passes over a coil that is either heated or cooled by water piped from the boiler room or chilled water plant. Can provide both cooling and heating. Air handling is usually constant velocity. Temp control is provided by local thermostats, which control the flow of hot or cold water to the coils. The air-handling system is a dedicated outdoor air system, and relies on 100 percent outside air. Because exhaust air is not recirculated, energy recovery between exhaust and supply air stream is common. +Typical Application: -Well suited to spaces with moderate fresh air and dehumidification requirements, such as office buildings, schools, and residential hotels and dorms. They can also be a good choice for spaces with high demands for cooling, for example, cool-load driven labs. +Advantages: -Compared to all-air system, it's quieter, provide more constant airflow, and better control of humidity. Can operate more efficiently than comparable all-air systems and the components can be 70 percent smaller. This reduces the building area set aside for these components. Disadvantages: -Higher upfront costs. Req. more wet piping, w/ possibiltity of leaks. Not suitable for space that req. very high levels of dehumidification or unusually high volumes of fresh air. Limited heating capacity. In bldgs with high clngs or high heating demands, a hydronic convector at exterior walls may be req. +Common Building Types: -Hospitals, Labs, Libraries, Nursing Homes, Offices
Constant Air Volume (CAV)
+An all-air system which is controlled by a master thermostat that connects to controllers that adjust the flow of hot and cold water to the central heating and cooling coils, thereby regulating the temperature of the air flowing through the system. +Typical Applications: -Typically used in spaces that have large open areas, few windows, and uniform loads, such as lobbies, department stores, theaters, auditoriums, gyms, and exhibition halls +Advantages: -Offers a high degree of control of air quality. Comparatively simple and easy to maintain +Disadvantages: -Entire area is served by the system is normally a single one, with no possibility for individual temperature control of separate zones. Use considerably more fan energy +Common Building Types: -Arenas, Exhibition Halls, Auditoriums, Theaters, Labs, Worship
Closed-Loop Heat Pumps
+An all-water system. A water-to-air unit in each space that provides heating, cooling, and fresh air. The water source for all the system in the building circulates in a closed loop of piping. Control valves allow water to circulate through a cooling tower in the summer and a boiler in the winter, and to bypass both the boiler and the cooling tower in spring and fall and at any other time when the heating and cooling needs of the various rooms in the building balance one another. +Typical Applications: -Well suited for hotels containing chronically overheated areas (kitchens, laundry, assembly, rooms, restaurants) +Advantages: -Efficient system in which heat extracted from overheated areas can be used to heat under-heated areas +Disadvantages: -Expensive system to install, and careful economic analysis is needed to determine if the high installation costs can be balanced by energy savings. Humidity cannot be closely controlled. +Common Building Types: -Apartments, Hotels, Motels, Dorms
Fan-Coil Terminals
+An all-water system. Hot and chilled water are used. At each terminal, a fan draws a mixture of room air and outdoor air through a filter and blows it across the heated or chilled coil and then back into the room. A thermostat controls the flow of hot and chilled water to the coils to maintain a comfortable room temp. Air exhaust is provided separately. +Typical Applications: -Well suited for buildings with many zones, all located on exterior walls, such as school, hotels, motels, apartments, and office buildings. +Advantages: -No fan room or ductwork spaces are req. in the building. The temp of each space is individually controlled. Install costs are low. +Disadvantage: -Humidity cannot be closely controlled. May generate more noise than centralized air handling systems. Maintenance must take place within the occupied space. +Common Building Types: -Apartments, Factories, Hospitals, Hotels, Motels, Dorms, Libraries, Nursing Homes, Offices
Hydronic Convectors
+An all-water system. Hot water (sometimes steam) from the boiler room is circulated through fin-tube convectors consisting of horizontal pipes with closely space vertical fins mounted inside a simple metal enclosure. The heated fin, working by convection, draw cool room air into the enclosure from below, heat it, and discharge it out the top. Thermostats manage temps by adjusting the flow of water in the hydronic piping. +Typical Applications: -Used alone in building where cooling is not required, and ventilation is provided by other means. Or they may be used as a supplemental source of heat in combination with other systems, for example to provide supplementary heating to perimeter floor areas where heat loss occurs through the exterior wall. +Advantages: -Economical to install and operate +Disadvantages: -Cooling, humidity control, and ventilation must be provided by other means +Common Building Types: -Apartments, Libraries, Offices, Worship, Schools
What are the HVAC Distribution System Options?
- Water Systems - Air Systems Note: Both are generally inexpensive. When you combine water and air systems, then it becomes very expensive.
Exit Stairway rules
- interior exit stairway must be completely enclosed. -bldg 4+ stories... 2-hour rated -bldg >4 stories... 1-hour rate -stories includes basements, excludes mezzanines
Drainage - Underground Systems
- piping min. slope of .3% -drain inlet - an opening in the ground that allows stormwater to run into the storm sewer - storm sewer - manholes for service wherever sewer changes direction, or max. 500ft apart
Radon mitigation strategies
- sealing cracks in floors, walls, and foundations - venting the soil outside the foundation wall - depressurizing the voids within a block wall foundation -ventilating the crawl space with a fan -using vent pipe without a fan to draw air from under a slab to the outside (passive sub-slab depressurization) -using a fan-powered vent to draw air from below the slab (active sub-slab depressurization) -using a fan-powered vent to draw air from below a membrane laid on the crawl space floor
Some basic concepts in plumbing:
-1 PSI will raise a column of water 2.31 feet -Static pressure is the pressure of non-moving water -Height limit for sucking water is 33 feet... static head equivalent of atmospheric pressure
What is the main Air and Water system?
-Active Chilled Beam
indoor air quality concerns
-Carbon Dioxide -Carbon Monoxide -Ventilation -Infiltration -Air Pollution Temperature Inversion
Mechanical Heating Options - Name 4
-Central Boiler (Water) -High and Low Pressure Steam -Heat Pumps and Electrical Devices -Fossil Fuels
Mechanical Cooling Options - Name 3
-Chiller (Refrigerant) -Direct Expansion -Rooftop Cooling
Psychrometric Chart - 6 Categories
-Dry bulb Temp - vertical line -Absolute Humidity - horizontal line -Saturation Line - top curved line -Relative Humidity - curved lines -Wet Bulb Temp - diagonal lines from saturation line -Dew point Temp - horizontal line
Building Orientation - Optimum Orientation Angle
-Hot-Humid 5 degrees -Cool 12degrees -Temperate 17.5 degrees -Hot-Arid 25 degrees
Common Causes of Sick Building Syndrome
-Moisture (mold) -Combustibles (carbon monoxide) -Volatile Organic Compounds -Poisonous materials -Off gassing -Asbestos -Vermiculite -Radon -Polychlorinated biphenyls (PCBs)
Mechanical Heating Energy Options - Name 3 - The energy supply
-Natural Gas - cleanest and the most efficient. -Oil - No. 2 is the grade most commonly used in residential and light commercial boilers, while no. 4 and no.5 are used in larger commercial applications -Coal -
Automobile Circulation
-Road should be limited to max slope of 15%, although 10% or less is preferable -transition slope of one-half of the max slope between road and level areas -1/4in per foot - crown slope to edge
Active Solar Design
-Solar designs that rely on the use of mechanical or electrical devices to convert sunlight into electricity. -Requires 3 components. a collector. a storage device. a distribution system -Common storage devices are water for water systems and rock beds for air systems. Phase change materials can be used but they are expensive.
Passive Solar Design - Thermal Storage Wall
-Trombe Wall - the common form of thermal storage wall. constructed of masonry with vents at top and bottom to allow heated air to circulate out -Water is more effective than concrete or masonry because it has a higher specific heat and can store more energy
What are the factors affecting human comfort?
-air temp -relative humidity -mean radiant temp -air motion -air purity -sound -vibration -light
Rules for Ventilation in attics, crawl spaces, and similar spaces:
-attic, net free ventilation must be at least 1/150 of the area of the space ventilated. May be reduced to 1/300 with exceptions -crawl space, 1/150 of the space. if ground surface is covered with a Class I vapor, then 1/1500 allowed
What are some the primary element sfor HVAC System uses?
-boilers and chillers -air handlers -room ventilation -filtration -heat exchange -water heating -water treatment -pumps
Openings in Corridors
-doors placed in a 1-hour corridor must have a fire rating of at least 20mins. -glazing in a 1-hr corridor must be 3/4-hour -duct penetration, must have a damper and at least 20min rating
The means of egress consist of 3 parts:
-exit access -the exit -exit discharge
Pedestrian Circulation - Collector walks
-located next to parking. min. 6ft wide -1/4in per foot slope
Knowing the occupancy classification is important in determining other building requirements, such as
-maximum area -number of floors allowed -how a bldg must be separated from other structures -calcs of occupant load -egress design -interior finish reqs -use of fire partitions and fire barriers -fire detection and suppression systems -ventilation and sanitation reqs -other specials restrictions
Utilities - Building Sewer
-min. slope is .5% to 2.0% -greater slope required for smaller pipes -pipe dia of 2.5" ... 1/4in per foot -pipe dia of 3" - 6"... 1/8in per foot -pipe dia of 8"+... 1/16in per foot
Requirements for All Stairways
-occupant load more than 50, at least 44in wide or as wide as determined by multiplying the occupant load by .3 or .2, whichever is greater. -occupant load less than 50, 36in wide -if stairway the accessible means of egress, clear width is 48in between handrails
Human comfort is based on the quality of the following primary environmental factors:
-temperature -humidity -air movement -temperature radiation to and from surrounding surfaces -air quality -sound -vibration -light
Aboveground Drainage System
-use pervious paving, sheet flow, gutters, and parking areas, ground swales, and channel to manage runoff and direct it appropriately. -.5% slope -most paved surfaces, 1.5% slope
Other notes about Pluming Systems:
-velocities above 10 feet per second make undesirable noise -in quiet areas, velocity should remain below 6 feet per second -pressure loss is a balance between diameter and flow rate -smaller diameters equal greater friction - pipe size
Identify two key design criteria Air-and-Water Systems typically must satisfy.
1) All required heating and cooling loads for perimeter spaces. 2) Simultaneous heating and cooling requirements of different spaces (zones) during intermediate seasons.
Name three key characteristics of Air-and-Water HVAC Systems.
1) Cool and heat both air and water. 2) Selective heating and cooling is possible by distributing conditioned air and water to zones throughout the conditioned perimeter building spaces. 3) Air supplied is termed "primary air" to differentiate it from secondary or recirculated air.
What are some of the disadvantages of Air-and-Water HVAC Systems?
1) Requires special trained staff for maintenance and change over between seasons. Intermediate season design is critical. 2) Controls of Air-and-Water Systems are more complicated than All-Air Systems and humidity can't be as tightly controlled. 3) Induction and fan-coil terminal units require frequent in space maintenance.
What are the advantages of Air-and-Water HVAC Systems?
1) Saves building space. Water specific gravity and density higher than air's therefore the cross sectional area of water piping is less that of air ductwork. A large part of the heating and cooling loads are addressed by the water portion of the system making the ductwork distribution requirements smaller than an All-Air System. 2) Return air system can be eliminated by sizing the primary air to equal the ventilation requirements or balance the exhaust air requirements. 3) Air handling system is smaller than an all air system yet positive ventilation is ensured. 4) Zones can be independently controlled and their heating and cooling requirements satisfied separately or simultaneously. 5) Space heating can be provided by only the water system without air system operation if designed to do so. 6) By taking all primary air from outdoors, cross contamination between rooms can be reasonably controlled.
Causes of Poor Indoor Air Quality
1. Chemical contaminants from indoor sources 2. Chemical contaminants from outdoors sources 3. Biological contaminants 4. Poor ventilation
Electrical Principles - Power service comes in two general forms:
1. Direct Current - which basically heats electrons at a constant rate 2. Alternating Current - reads as a sign curve which oscillates form feeding power forward and backwards across the circuit, and when plotted creates a sign curve Note: the alternating current is the most common form of power provided to building applications. Direct current is sometimes used in buildings for specialty equip. like elevators/escalators, or possibly low voltage systems
Passive Solar Design - Name the Most Commonly used passive design systems
1. Direct gain systems 2. Indirect gain systems 3. Thermal storage wall 4. Phase change materials 5. Greenhouse design 6. Roof pond 7. Convective loop system or thermosiphons
Strategies for Maintaining Good Indoor Air Quality
1. Eliminate or reduce sources of pollution 2. Control ventilation 3. Establish good maintenance procedures 4. Control occupant activity - no smoking policy, etc 5. Provide appropriate filtration
Categories of Materials to Consider from an Indoor Air Quality Perspective:
1. Flooring - carpet, resilient flooring 2. Wall and Ceiling materials 3. Paints and Coatings 4. Adhesives and Sealants 5. Engineered wood products
4 Stages of HVAC Components - Image
1. Fuels (Electricity, Propane, Natural Gas, No.2 oil, Anthracite Coal) 2. Plant System (Cooling - Compressive Refrigeration, Absorptive Refrigeration, Evaporative Cooling) (Heating - Furnace, Boiler) 3.Distribution Systems (Water or Air) 4. Delivery components include the radiators and diffusers
Electrical - What are the 2 general formats for Distribution Stages?
1. Primary Distribution - A central location to distribute power to various parts of the building. (Switchgear). Distributes power to panel boards for secondary distribution 2. Secondary Distribution - Fed by the switchgear, the panel boards feed circuits to other components within the building. Larger buildings may require electrical closets due to increased demand Note: smaller buildings are generally fed with 1 panel board and that's when you hear about the power going out and you need to flip a circuit to get the power back on - circuit panel
Mechanical | Air-Cooled and Water-Cooled Chillers Compressor, what the commonly used 5 types?
1. Scroll-which is most often air-cooled 2.Screw-which is both air & water cooled 3.Centrifugal-which is water cooled 4.Absorportion chillers (which actually don't use compressors)
4 phases of Life Cycle Assessment
1. determine the purpose and goals of doing the study 2. inventory analysis - determining and quantifying all the inputs and outputs of the product under study 3. impact assessment - characterizes the effects of the processes found in the inventory analysis in terms of their impacts of the environment 4. improvement analysis - provides suggestions on how to reduce the environmental impact of all the raw materials, energy, and processing required for the product or construction activity
Adhesives - 3 types of low-emission and zero-VOC adhesives
1. dry adhesives - contain resins stored in capsules released by pressure 2. water-based adhesives - contain latex or poyvinyl acetate 3. natural adhesives - containing plant resins
Methods of controlling site noise
1. maximize the distance between the source of the noise and the receiver. 2. avoid hard surfaces near the source noise 3. avoid parallel hard surfaces 4. plant evergreen trees and shrubs densely between the noise source and receiver 5. make use of masking sounds - water fountains, etc 6. design building feature to block noise.
What 4 ways can water be classified?
1. potable water 2. rainwater 3. graywater 4. blackwater
4 main stages in a product's life cycle
1. raw material acquisition 2. manufacturing 3. use in the building 4. disposal or resuse
Basic principles for designing sound barriers
1. solid barriers are generally better at blocking high-frequency sounds than low. 2. the barrier is best placed as close as possible to either the source or the receiver. 3.if barrier is place close to the noise source, it should be at least 4x as high as the distance from the source to the barrier 5.for blocking noise from a point source, a short barrier should be at least 4x as long as the distance from the barrier to the source, or the distance from the barrier the receiver, whichever is shorter 6.barrier should have a density of at least 5lbm and be solid
The two basic ways heat is lost in a building?
1. through the building envelope 2. through air infiltration
Parking Drainage Slope
1.5% and 5%, but for convenience in calculating, 2% or 3% can be used when figure the slope of parking lots
Mechanical What are the 4 main chiller components which exist in both air-cooled and water-cooled chillers?
1.Compressor 2.Condenser 3.Evaporator 4.Expansion Valve
Calc: Roof Area 10,000sf. Annual rainfall of 20in 25% lost to evaporation/runoff/etc. What is annual collected rainfall total?
((10,000sf)(20in)(1yr))(.75)(.6 conversion to gal) = 90,000 gal to be used in building
Variable Air Volume (VAV)
+An all-air system which accommodates thermal load changes by varying the flow of supply air into a conditioned space instead of varying the temperature of the supply air. +Typical Applications: -Most versatile and most widely used system for heating and cooling large buildings +Advantages: -This system offers a high degree of local temperature control at a moderate cost. It is economical to operate and virtually self-balancing +Disadvantage: -Limited in the range of heating or cooling demand that may be accommodated within a single system. When one area of a building needs heating while another needs cooling, this system cannot serve both areas without help from a secondary system +Common Building Types: -Arenas, Exhibition Halls, Auditoriums, Theaters, Factories, Hospitals, Hotels, Motels, Dorms, Labs, Libraries, Nursing Homes, Offices, Worship, Schools, Shopping Centers, Stores
Indoor air quality - common problems
-Particulates in the air -Gaseous pollutants -Stagnant air flows -Water presence (water, mold, evaporation problems)
What are the 2 main All-Air Systems?
-VAV (Variable Air Volume) -CAV (Constant Air Volume)
The body loses heat in 3 primary ways. What are they and explain each.
1. convection - the transfer of heat through the movement of gas or liquid 2. evaporation - occurs when moisture changes to a vapor as a person perspires or breathes 3. radiation - transfer of heat energy through electromagnetic waves from one surface to a colder surface
Accessory Occupancy - 3 exceptions:
1. live/work unit 2. group H (Hazards) occupancies must be separated from other occupancies 3. dwelling units and sleeping units need fire partitions between them
dead end corridor
A corridor that is closed at one end, usually limited to 20 feet in length.
Fire Barrier
A fire-resistance-rated vertical or horizontal assembly of materials designed to restrict the spread of fire in which openings are protected
Demand control ventilation
A system designed to adjust the amount of ventilation air provided to a space based on the extent of occupancy. The system normally uses some type of sensors
Radiation Spectrum
The entire range of electromagnetic radiation extending from 0 hz to 1023 hz. This includes visible light as well as infrared radiation, radio waves, and gamma rays among others
Mechanical | Air-Cooled and Water-Cooled Chillers Evaporator, what does it do?
The evaporator transfer heat from the cooled air or water through the boiling process of the refrigerant.
dew point
The temperature at which condensation begins
Principle of Refrigeration - Compressive refrigeration for Plant Systems - Cooling
based on transfer of heat during the liquefaction and evaporation of a refrigerant.
thermochromic glazing
changes darkness in response to temperature
Photochromic glazing
darkens under the direct action of sunlight
Guardrails
min. 42" high and 4" max opening at floor. 36min allowed for group r-3 occupancies, which are not more than 3 stories above grade
Solar Constant
the amount of solar energy received per unit area, per unit time on a surface at right-angles to the sun's beam at the edge of the Earth's atmosphere
Mean Radiant Temperature
the average temperature of the surfaces that will exchange thermal radiation in a space
Ohm's Law
the current in a circuit equals the voltage difference divided by the resistance. If voltage goes up, current goes up.
International Fuel Gas Code regulates what?
the installation of fuel gas distribution piping and equipment, fuel-gas fired appliances, and fuel gas-fired appliance venting system
Transition-metal hydride electrochromics
• Changes from transparent to reflective • Coatings of nickel magnesium
What are the 4 All-Water Systems?
1.Fan-Coil 2.Closed Loop heat Pumps 3.Hydronic Convectors (heating only) 4.Hydronic Radiant Heating and Cooling
Stairs - Max. distance permitted between landings?
12 ft measured vertically
What is the comfortable relative humidity range?
30% and 65%
Parking Value per Car -
400 square ft per space - includes aisles, drives, landscaping
Parking - Compact Size
7ft 6in wide X 15ft long
Parking - Standard Size
9ft wide X 19ft long
Smoke Barrier
A continuous membrane, either vertical or horizontal, such as a wall, floor, or ceiling assembly, that is designed and constructed to restrict the movement of smoke. It is a passive form of smoke control.
Fire Damper
A device installed in ductwork that limits the spread of fire, usually activated by the melting of a link that holds it in its normally open position.
Exit access doorway
A door or access point along the path of egress travel from an occupied room, area, or space where the path of egress enters an intervening room, corridor, unenclosed exit access stair or unenclosed exit access ramp
Radon
A gas that arises from the earth where radioactive materials are present. -a cause of sick building syndrome
Psychrometric Chart
A graph used in air-conditioning and showing the properties of air-system mixtures.
Polychlorinated biphenyls (PCBs)
A group of industrial compounds used to manufacture plastics and insulate electrical transformers, and responsible for many environmental problems. -a cause of sick building syndrome
Floor Area Ratio
A guideline used to regulate building density. The ratio is calculated by dividing a building's floor area by the ground (lot) area or by dividing the number of floors in a building by the portion of the lot covered by the building.
Exit passageway
A horizontal fully enclosed portion of an exit that is only used as a means of egress
Smoke Damper
A listed device installed in ducts and air transfer openings that is designed to resist the passage of smoke.
Asbestos
A long, thin, fibrous silicate mineral with insulating properties, which can cause cancer when inhaled. Can be found in pipe and blown-in insulation, asphalt flooring, vinyl sheet and tile flooring, construction mastic, ceiling tiles, textured paints, roofing shingles, cement siding, caulking, and vinyl wall coverings -a cause of sick building syndrome
Coproduct
A marketable byproduct from a process that can include materials traditionally considered to be waste but that can be used as raw materials in a different manufacturing process.
Eutrophication
A phenomenon in which a body of water becomes rich in nutrients
Renewable materials
A product that can be grown, naturally replenished, or cleansed at a rate that exceeds human depletion of the resource.
Renewable product
A product that can be grown, naturally replenished, or cleansed at a rate that exceeds human depletion of the resource.
Accessory Occupancy
A space or room that is ancillary to a main occupancy but that does not exceed 10% of the floor area of the story in which it is located.
Fire Partition
A wall assembly with a 1-hr fire resistance rating.
Bulk Plane Restriction
A zoning technique that establishes an imaginary inclined plane beginning at the lot line or the center of the street at a given elevation and slopes at a prescribed angle toward and over the lot. The building cannot extend beyond this plane.
Where are Air-and-Water HVAC systems typically used?
Air-and-Water HVAC is primarily used in perimeter building spaces with high sensible heating and cooling loads: Office buildings, schools, hospitals, libraries and others where the systems can meet and comply with the design criteria.
Formaldehyde
An air pollutant that is a colorless chemical used to manufacture building materials and many household products, such as particleboard, hardwood plywood paneling, and urea-formaldehyde foam insulation.
Life Cycle Assessment
Analysis of environmental impacts of products from the design stage through end-of-life.
Incidental Use Area
Ancillary to the main occupancy and has the same classification as the nearest main occupancy but poses a greater level of risk to that occupancy. Must be separated from the main occupancy by a smoke barrier, and the sprinklers are required only in the incidental use area.
Public Way
Any street, alley, or similar parcel of land essentially unobstructed from the ground to the sky that is permanently appropriated to the public for public use and has a clear width of not less than 10ft.
Principle of Refrigeration - Absorptive Refrigeration for Plant Systems - Cooling
Closed loops system with salt water or brine and produces chilled water which produces heat when water evaporates
evaporative cooler
Device for cooling homes in dry climates that cools the incoming air by humidifying it.
Geothermal
Energy derived from the heat in the interior of the earth. Uses ground-source heat pump. initial costs higher than that of conventional equip, long term costs are lower. Most beneficial in bldgs that req significant space and water heating and cooling over extended hours of operation (single-family homes, multifamily, schools)
Watt (Power, P)
Equivalent to 1 joule per second, and measures how fast electrons are moving 1 watt is = 3.412 BTU
Two Types of Green Roofs
Extensive and Intensive
heat exchanger
Extracts embodied heat from water to be reused as heat for HVAC system
Electrical - What are the design implications of power supply and what impact that has on larger building?
For a larger building, there will be a switch gear, and the purpose of the transformer and switch gear is to step down (sometimes step up) the power that is being fed from the grid. which will step it up/or down to the level that's required for that building's applications. The transformer will step that power down, which is a distribution center for various panels within the building. Furthermore, the switch gear can feed a number of different panels that are going to be isolated in certain circuits throughout the building
Furnace for Plant Systems - Heating
Gas or oil fired units heating air which distributes through a distribution system. - basically using a gas or oil fire to heat the air itself
Electrochromic glazing
General term for a type of glazing that changes from either a dark tint or milky white opaque to transparent with the application of an electric current.
spectrally selective glazing
Glazing that transmits most visible spectrum but blocks upto 80% infrared spectrum
Glare Control
How well a window covering shields from direct, bright, harsh light - light that obscures occupant view of items such as TV and monitor screens. - A good choice for glare control is a glass with a VLT from 50% to 70% combined with the lowest possible SHGC.
One exception to mixed occupancy concerns small storage rooms. What is it?
If a room or space used for storage is less than 100sf and is accessory to another occupancy, it is classified as part of that occupancy. For example, a 75sf storage room in a business office would be a B occupancy, not an S occupancy. Storage rooms greater than 100sf are generally classified as S occupancie, but the local building official may classify them as the same occupancy in which they are located.
Lead
Lead exposure comes from paint in homes built before 1978, and from soil and household dust that contains material from deteriorating lead-based paint. Depending on building type, covering the wall with a new layer of gyp or simply painting may be acceptable.
Resistance (R or Omega Symbol)
Measured in Amps Amount of flow through a circuit overall
Current (I)
Measured in amps Amount of flow through a circuit Note: things being pushed through a pipe or veins, it's a circulatory principle
Voltage (V)
Measured in volts Amount of force or potential in circuit Note: so how much is that flow being pushed through that channel
Radiative Cooling
Passive or active design strategy that uses thermal mass to collect and store heat during the day for release at night. Also known as nocturnal cooling and night cooled mass
Fee in Lieu
Payment of money by developer in place of meeting all or part of stormwater performance standards
Building Pressurization - When vents are pulling air out of the space faster than it's being pulled in, it creates what type of pressure?
Positive pressure on the openings of the building, thus resulting in uncomfortable conditions and dangerous problems with operable openings. Example: slamming doors, bowing windows, possibly windows that are cracking or breaking
SHGC (Solar Heat Gain Coefficient)
Solar radiation transmitted through assembly ranging from 0-1.0 allows most transmittance
Environmental Product Declaration
Standardized report of a products environmental impact throughout its lifecycle
Exit Discharge
That portion of the means-of-egress system between the termination of the exit and a public way.
Exit Access
That portion of the means-of-egress system that leads from any occupied portion in a building or structure to an exit. Does not need to be protected.
Ton
The amount of cooling required to convert a ton of water to ice in a 24 hour period. A ton is 12,000 BTUH
Analemma
The analemma is a figure-8-shaped diagram that shows the declination of the sun (the angle that the sun is from the equator), for each day in the year. If you took a snapshot of the sun at the same time each day (from the same location), the Sun would make a figure shaped like an analemma during the course of a year (this is because the Earth is tilted on its axis and because it doesn't orbit the Sun in a perfect circle).
Fire Area
The area and closed and bounded by firewalls, fire barriers, exterior walls, or horizontal assemblies of a building
Workplane
The assumed height at which work is performed, usually considered to be at desk height, 30 in. above the floor.
Mechanical | Air-Cooled and Water-Cooled Chillers Compressor, what does it do?
The compressor lowers the pressure of the refrigerant in the evaporator (so that it boils) and raises the temperature and pressure of the refrigerant gas. It also circulates the refrigerant in the system.
Mechanical | Air-Cooled and Water-Cooled Chillers Condenser, what does it do?
The condenser transfers heat from the refrigerant to the outdoor cooling medium (air or water), condenses the refrigerants, changing it from a gas to a liquid
Conduction
The direct transfer of heat from one substance to another substance that it is touching.
Exit Access Travel Distance
The distance that an occupant would have to travel to get from the most remote point in the occupied portion of the exit access area, along the natural and unobstructed path of horizontal and vertical travel, to the entrance to the nearest exit.
Mechanical | Air-Cooled and Water-Cooled Chillers Expansion Valve, what does it do?
The expansion valve drops the pressure of the refrigerant liquid from high to low pressure. This separates the high and low pressure sides of the system.
Runoff Coefficient
The fraction of total precipitation that is not absorbed into the ground.
Visible Light Transmittance (VLT)
The fraction of visible light that passes through a glazing material
enthalpy
The heat content of a system at constant pressure
sensible heat
The heat energy that causes a change in temperature of a substance but does not contribute to a change in state
Drainage easement
The legal rights granted by a land owner to a grantee, commonly a governmental entity, allowing the use of private land for Stormwater management
Acidification
The lowering of the pH of a solution.
Coefficient of heat transmission
The overall rate of heat flow through any combination of materials, including air spaces and air layers on the interior and exterior of a building assembly.
Daylight Autonomy
The percentage of an area that meets a minimum daylight illuminance level or specified fraction of the operating hours per year. also referred to as special daylight autonomy
Exit
The portion of the egress system that provides a protected path of egress between the exit access and the exit discharge.
Effective Aperture
The product of visible transmittance and the window to wall ratio
Power (P)
The rate of energy transfer Energy / time (hours)
Daylight Factor
The ratio expressed as a percentage othe indoor aluminates at a point on a horizontal surface to the unobstructed Exterior horizontal illuminance
Shading Coefficient
The ratio of solar heat transmission through a particular glass to the solar heat transmission through double-strength clear glass.
Window-to-wall ratio
The ratio of the net glazing area in your room or space to the gross exterior wall area
Net Metering
The requirement that a utility pay and charge equal rates regardless of which way electricity flows as a part of the utility Grid.
Dry Bulb Temperature
The temperature of air measured by a thermometer freely exposed to the air
embodied energy
The total amount of energy used to extract materials and manufacture, transport, install, and use a product across its life cycle.
Radiation
The transfer of energy by electromagnetic waves
Convection
The transfer of heat by the movement of air
Graywater
The water from washers, sinks, and baths. should have interceptors to prevent the flow of grease and hair into the systems. Only cost effective in new construction where separate piping can be installed and where the demand for nonpotable to potable water is relatively high, such as for laundries and car washes.
Sustainability - Carpet
There are 3 major considerations for sustainability: raw material use, raw material disposal, and impact on indoor air quality.
Green Roof on Metal Deck
Thermal Barrier > Waterproofing > Root Barrier > Rigid Insulation > Drainage Layer > Filter Fabric > Growth Medium > Plants
Earth Sheltering
Using Earth against building walls for external thermal mass to reduce heat loss and to easily maintain a steady indoor air temperature. -does not require much insulation, the insulation must be correctly designed to keep the indoor temp comfortable and to prevent condensation from forming on cool inside walls, especially in a humid environment
Low Volatile Organic Compound Content
VOCs in paint, carpet, composite wood products, and so on can be released into the indoor air and create health risks
ground light
Visible light from the sun and sky, reflected by exterior surfaces below the plane of the horizon
Fire Wall
Wall with a fire-restive rating and structural stability that separates buildings or subdivides a building to prevent the spread of fire.
Recovered materials
Waste or byproducts that have been recovered or diverted from solid-waste disposal. The term does not apply to materials that are generated from or reused within an original manufacturing process.
Boiler for Plant Systems - Heating
Water filled vessel in which fluid is heated with gas or oil. Evaporated fluids are distributed for heat.
Green Roof on Concrete Slab
Waterproofing > Root Barrier > Rigid Insulation > Drainage Layer > Filter Fabric > Growth Medium > Plants
hydrologic soil group
a classification of soils based on their potential for runoff when thoroughly wet. group A - contains soils high in gravel and sand that have high permeability and low runoff potential - group D which contains clayey soils that have low permeability and high runoff potential
Vermiculite
a yellow or brown mineral found as an alteration product of mica and other minerals, and used for insulation or as a moisture-retentive medium for growing plants. -a cause of sick building syndrome
Raw Material Acquisition (in regards to LCA)
acquisition of raw materials and energy from mining, drilling, or other activities; processing of raw materials; transportation of raw materials to processing points
closed loop active solar gain
antifreeze or other transfer medium is heated in collector, sent to heat exchanger to extract heat, extracted heat warms water that is distributed
The general comfortable air temp for the human body is?
between 69 degress and 80 degrees, with a tolerable range from 60 degress to 85 degrees, depending on relative humidity
Building Shape - Temperate Climate
building shape has less of an effect. however, building elongated in the east-west direction still offers some advantages for winter solar heat gain, daylighting, and minimizing heat gain in summer
Sources of VOCs
chemical solvents: paint, varnish, gasoline, nail polish, adhesives photocopiers, cigarettes, stoves, building materials and furnishing, and many more
Transparent Insulation
consists of a relatively thick layer of poly carbonate honeycomb material, acrylic foam, or fiberglass sandwiched between layers of glazing
Allowable Floor Area based on:
construction type, occupancy, fire sprinkler, building frontage on a public way or open space
manufacturing (in regards to LCA)
conversion of processed raw materials into useful products; manufacturing or fabrication of materials into a final product; packaging of the product; transportation of finished product to site
Green Roof - Intensive
deep soil of 12inches or more. usually constructed over a structural deck due to its heavy loads. typically 12psf to 300psf
Disposal (in regards to LCA)
demo of product used in building; conversion of waste into other products; waste disposal of product; reuse/recycle of product if not disposed/converted
International Residential Code regulates what type?
detached one- and two-family dwellings and multiple one-family dwellings (that is, townhouses) not more than 3 stories high with separate means of egress
Glazing - Low-e
double gazing that includes a thing film or coating placed somewhere in the glazing cavity.the film or coating prevents the loss of this heat; instead, the heat is reflected back into the room. When used with an argon gas fill to reduce convection. very efficient at preventing heat loss
What is the least cost effective heating source, although it's the most power efficient?
electricity
Sustainability - Concrete
environmental impact can be reduced by incorporating fly ash admixtures, using recycled aggregates when possible and using low-waste form-work.
Passive Solar Design - Phase Change Materials
eutectic salts that change from a solid to a liquid at a fairly low temp. they store large amounts of heat because they store latent heat as they undergo the phase change from solid to liquid. At night, the stored heat circulates into the building
Daylighted Zone
extends 1.5x the window head height into the room. when light-shelf used... 2.0 - 2.5x the window height
Life-Cycle Cost Analysis
first cost, including the cost of installation maintenance, life expectancy, and replacement cost
super windows
glazing units that combine 2 low-e coatings with gas-filled cavities between 3 layers of glass.
surface temperature
if the surface temp of the surroundings are colder than the surface temp of the skin, the body loses heat through radiation; if the surrounding surfaces are warmer than the skin, the body gains heat
Use and Maintenance (in regards to LCA)
installation/construction of product into building; long-term use of the product through life; maintenance/repair of the product throughout life
Insulation
is made from a variety of materials such as fiberglass, mineral wool, polystyrene, polyisocyanurate, polyurethan, and cellulose.
infilatration
is the transfer of air into and out of a building through open doors, cracks around windows and other openings, flues and vents, and other gaps in the exterior construction. Unless a building is well sealed, infiltration can account for more heat loss than transmission through the walls and roof. No building is perfect, there is always infiltration.
Cellulose Insulation
is treated, ground-up newspaper that is blown into wall cavities and attics; it is normally gray in color
Different forms of Insulation
loose fill batts rigid foam boards spray-on foam structural insulated panels
wet bulb temperature
more critical measure of heat in high humidity because it is an indicator of physical stress caused when the human body is near the upper limits of temperature regulation by perspiration
General rule of thumb for Egress Width of Exits
multiply the occupant load by a factor of 0.3 in for stairways or 0.2 for egress components other than stairways
Dynamic buffer zone?
new outer layer of glazing built around an existing building. prevents and controls condensation that may result from remodeling and upgrading the existing building's vent., heating, cooling systems to higher humidity levels. The buffer zone is ventilated with dry, preheated air during winter months.
What's considered a high-rise building?
one with occupied floors more than 75ft above the lowest level of the fire department vehicle access.
Passive Solar Design - Convective Loop System or Thermosiphons
place solar collector below the inhabited space. the air within the space is circulated by natural convection as the warm air rises and cool air falls back to the collector. the cycle continues indefinitely.
Air Barrier - Air leakage solution
provide continuous barrier around the conditioned spaces in the building
Building Shape - Hot-Arid
squarer shapes are better. for external-load dominated bldgs, the plan should include open courtyards; for internal-load, a solid multistory arragement works best
Passive Solar Design - Roof Pond
stores heat in large water-filled bags on the roof. in winter, during the day the bags heat up. at night, insulation is moved over the roof pond, and the bags release heat downward into the building. -the same system can be reversed in the summer to cool the building by radiation. During day, bags covered with insulation, so they absorb heat only from the building. at night, the insulation is removed and the absorbed heat is transferred upward and away from the building.
Superinsulation
technique of providing higher levels of insulation that normally used, tightly sealing all joints and cracks and preventing any thermal bridges
Air Barrier - Location
the air barrier within a wall or roof assembly is not important for it effectiveness. However, the air barrier generally should be located behind the exterior cladding and outside the sheathing. Makes it easier for install
Peak Heat Loss
the amount of heat lost at design outdoor and indoor conditions which must be made up by the HVAC system to maintain occupant comfort
latent heat
the heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature.
specific heat
the heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).
Full Load Hours
the maximum output potential of a heating/cooling system in one hour and is used to size HVAC equipment
Site Acoustics
the most effective method of controlling site noise is the use of solid sound barriers. Wood or conrete block or earth berms.
Balance Point Temperature
the outdoor temperature at which a building makes a transition from a heating need to a cooling need
Relative Humidity
the ratio of the amount of water in the air at a give temperature to the maximum amount it could hold at that temperature
Psychrometry
the study of the water vapor content of air
Fire Barrier extend from where to where?
typically from floor to bottom floor
Movable Insulation
typically used on windows that provide passive solar heating.
Economizers
use outside air to cool the building when weather conditions are appropriate (about 60 degrees)
Green Roof - Extensive
use soil less than 6 in deep, which is capable of supporting meadow grasses, sedums, herbs, and perennials
Principle of Refrigeration - Evaporative Cooling for Plant Systems - Cooling
water dropped over pads or tubes circulating air from outdoors
Open Loop active solar gain
water is heated directly in solar collector and distributed
