Division 4: Project Planning & Design Flashcards
What symbol represents the distance in feet from a noise source to the top of the sound barrier?
𝐴
What symbol represents the distance in feet from a noise source to the bottom of the sound barrier?
𝐵
What symbol represents the line-of-sight distance in feet from a sound source to a receiver?
𝐷
What symbol represents sound frequency in hertz (Hz)?
𝑓
What symbol represents effective height in feet?
𝐻
What symbol represents noise level in decibels (dB)?
𝑁
What symbol represents emissivity?
ε
What is emissivity?
The relative ability of a material’s surface to emit heat by radiation.
What is runoff?
Stormwater that accumulates on the site in excess of what can be absorbed by the ground.
What are the two types of drainage systems?
Aboveground and underground.
What are some elements of an aboveground drainage system?
Pervious paving, sheet flow, channels, gutters built into roadways and parking areas, and ground swales as part of the landscaping.
What are some elements of an underground drainage system?
Perforated drains and enclosed storm sewers that connect to either a municipal storm sewer system or a natural drainage outlet, like a river.
What is sheet flow?
Water that drains across a sloping surface, whether paved, grassy, or otherwise landscaped.
What is the minimum slope required for surface drainage on a very smooth and carefully constructed surface?
0.5%
What is the generally accepted slope required for surface drainage on most paved surfaces?
1.5%
What is the minimum slope required in pipes used for underground drainage systems?
0.3%
What is a drain inlet?
An opening in the ground, usually covered with a metal grate for safety and debris, that allows stormwater to run directly into the storm sewer.
What is a catch basin?
An underground reservoir that has a sump built into it.
Along a large storm sewer system, where are manholes required?
Wherever the sewer changes direction or spaced a maximum of 500 feet apart.
Storm sewers are always completely separate from sanitary sewer systems. True or false?
True
What are the three major factors that determine the required capacity of a drainage system?
The size of the area to be drained, the runoff coefficient, and the amount of water to be drained during the most severe storm anticipated by the design
What is a runoff coefficient?
The fraction of runoff water that is not absorbed into the ground
What is an n-year storm?
The most severe storm anticipated by a design, which has a statistical probability of occurring once every n years
In any given year, what is the probability of a 100-year storm occurring?
1%
In any given years, what is the probability of a 25-year storm occurring?
4%
In any given year, what is the probability of a 10-year storm occurring?
10%
What is a holding/detention/retention pond/basin?
A basin designed to collect, hold, and release stormwater runoff at a controlled rate, especially when the development of a site creates runoff in excess of the capacity of the existing storm sewer or drainage course
Sanitary sewers and storm sewers usually take precedence in planning because they depend on gravity flow. True or false?
True
What is the range for minimum required pipe slope?
0.5% to 2.0%
Why is the minimum required pipe slope a range?
Smaller pipes require greater slopes
What is the azimuth of the sun’s position?
The compass orientation of the sun, in degrees from south
What is the altitude of the sun’s position?
The apparent height of the sun, in degrees from the horizon
What is a passive solar energy system?
A system which collects, stores, and distributes solar energy without the use of mechanical equipment
Name some general categories of passive solar design techniques.
Direct gain systems
Indirect gain systems
Thermal storage wall
Trombe wall
Phase change materials
Greenhouse design
Roof pond
Convective loop system (or thermosiphon)
What is a direct gain system?
A passive solar design technique that lets in heat through south-facing glass and stores it in high-mass materials to be slowly released in the nighttime
What is an indirect gain system?
A passive solar design technique that heats a mass with the room’s air temperature and reflected sunlight then slowly releases that heat in the nighttime
What is a thermal storage wall?
A passive solar design technique that places a high-mass wall directly behind a south-facing glass wall and uses it to absorb heat during the day for release at night
What is a Trombe wall?
A type of thermal storage wall that is constructed of masonry with vents at the top and bottom to allow heated air to circulate out to the rest of the building
What are phase change materials?
Substances that absorb and release thermal energy when they change from one state to another
What is a common phase change material?
Eutectic salts
Why are eutectic salts a common phase change material?
They melt and freeze at around 70° F and can store and release latent heat as they undergo phase changes
What is greenhouse design?
A passive solar design technique that that features a large glazed area facing south with a heavy thermal mass that overheats during the day to circulate stored heat into the rest of the building during nighttime
What is a roof pond?
A passive solar design technique that places water-filled bags on the roof to absorb heat during the day, then moves insulation over the pond at night to release heat downwards into the building
What is a convective loop system or thermosiphon?
A passive solar design technique that places a solar collector below an inhabited space and employs natural convection to circulate air
What is an active solar energy system?
A system which collects, stores, and distributes solar energy using mechanical and/or electrical devices
What are four common uses of active solar energy systems?
Domestic / process water heating, space heating, space cooling, and electricity generation
What three components are required of a typical active solar energy system?
A collector, a storage device, and a distribution system
What are three reasons that wind power is impractical for individual building use?
Equipment costs are high, most jurisdictions do not allow its use on urban or suburban sites, and most project sites will not satisfy the requirements for wind speed and direction
What are two advantages of using photovoltaic cells?
Electricity is produced without pollution and the primary resource used is free
What are three disadvantages of using photovoltaic cells?
Initial costs are high, collectors need to be placed in locations that receive enough sunlight, and production is low during nights and winters
What is the optimal range of tilt angles for maximum energy generation using photovoltaic cells during the winter?
10° to 15° greater than the latitude
Considering the slightly lower morning temperatures, what is the approximate optimal orientation for a rectangular building?
Facing the longer dimension 15° east of south
What is an external-load dominated building?
A building for which energy use is determined mainly by the amount of heat loss or gain through its envelope
What are four examples of external-load dominated buildings?
Houses, apartments, condominiums, and warehouses
What is an internal-load dominated building?
A building for which energy use is determined mainly by the amount of heat gained from occupants, lighting, and equipment
What are five examples of internal-load dominated buildings?
Office buildings, hospitals, retail stores, schools, and laboratories
What are six materials that insulation could be made from?
Fiberglass, mineral wool, polystyrene, polyisocyanurate, polyurethane, and cellulose
What are five forms that insulation is available in?
Loos fill, batts, rigid foam boards, spray-on foam, and as parts of structural insulated panels
Most insulation types must be installed with a vapor barrier to be effective. True or false?
True
What are hydrochlorofluorocarbons (HCFCs)?
Ozone-depleting chemicals, used in the production of some insulations, that will be phased out by 2030
What is superinsulation?
The technique of providing higher levels of insulation than normally used, tightly sealing all joints and cracks, and preventing any thermal bridges between the exterior and interior
What is transparent insulation?
A system consisting of a layer of insulation (polycarbonate honeycomb, acrylic foam, or fiberglass) sandwiched between layers of glazing, which can allow light to pass while still providing insulation high insulation values
What is movable insulation?
Insulated elements that can be moved as needed
What are three common types of movable insulation?
Roll-down shutters, insulated shades or curtains, and swinging insulation panels
What is air leakage?
The movement of air into and out of a building by natural means
What is the stack effect?
The difference in air pressure between the top and bottom of a building due to a temperature differential
What is an air barrier?
A part of the building envelope system that limits infiltration and exfiltration
What is a vapor-permeable barrier?
A part of the building envelope system that allows water vapor to pass through it while keeping out liquid water and air
What are eight examples of vapor-permeable barriers?
Thin sheets of spunbonded polyolefin (house wrap)
Polyethylene
Elastomeric coatings
Liquid applied spray-on or trowel-on materials
Self-adhesive membranes
Sheathing sealed with tape
Silicon-based materials
Fluid-applied products
What is a vapor-impermeable barrier?
A part of the building envelope system that acts as both an air barrier and a vapor retarder
What is permeance?
A measure of how readily a material allows water vapor to pass through it
What is the unit of permeance?
Perm (one grain of moisture per hour per square foot per inch of mercury difference in vapor pressure)
What is earth sheltering?
Burying a portion of a building underground for thermal advantages
What are some advantages of earth sheltering?
More stable temperature conditions, protection from weathering, and natural soundproofing
What are the three types of earth-sheltered design?
Bermed, in-hill, and underground
What is a bermed building in earth-sheltered design?
One that is built above grade, with fill earth then bermed against its exterior walls
What is an in-hill building in earth-sheltered design?
One that is built into a hill, sometimes with the roof covered by earth
What is an underground building in earth-sheltered design?
One that is built completely below grade with a courtyard in the middle for access, daylight, and ventilation
Why are clay soils not appropriate for earth-sheltered designs?
They do not drain well and can expand with moisture
What is a green roof?
A system consisting of planting containers filled with vegetation, installed on top of a roof designed to hold this vegetation
What are some advantages of a green roof?
Reduced cooling and heating loads
Reduced storm runoff
Reduced ambient air temperatures
Air filtration
Reduced heat island effects
Protection from weathering
Acoustic insulation
Aesthetic appeal
What are the two types of green roofs?
Extensive and intensive
What is an extensive green roof?
One that uses soil less than 6” deep and is capable of supporting meadow grasses, sedums, herbs, and perennials
What is an intensive green roof?
One that uses soil at least 12” deep and is capable of supporting complex landscapes, including shrubs and small trees
A green roof must be constructed over a structural deck strong enough to hold the wet weight of the assembly. True or false?
True
What are three examples of materials that are inherently root resistant?
Polyvinyl chloride (PVC), ethylene propylene diene terpolymer (EPDM), and thermoplastic polyolefin (TPO)
What percentage slope should the structural deck of a green roof be at a minimum?
1.5%
What is a flood test?
A common test for verifying watertightness in a green roof by flooding the system in 2” of water for 48 hours then inspecting the interior of the building for leaks
Why is a drip irrigation system usually recommended over a spray irrigation system for green roofs?
A drip irrigation system delivers moisture more directly to the plant roots rather than allowing some of the water to evaporate
What is a cool roof (or reflective roof)?
One that is covered with a light-covered material that reflects more of the sun’s heat than it absorbs
What is the minimum reflectivity for a roof to be considered a cool roof?
0.65 when new and 0.50 at three years of age
