Site Analysis

detention pond

low lying area that is designed to temporarily hold a set amount of water while slowly draining to another location. They are more or less around for flood control when large amounts of rain could cause flash flooding if not dealt with properly

leech field

a component of a septic system, made up of underground pipes laid out below the surface of the ground

retention pond

a large basin designed to catch surface runoff to prevent its flow directly into a stream

swale

a low or hollow place, especially a marshy depression between ridges a water-harvesting ditch on contour vegetated swales can increase infiltration 1.5-2% for grass 4-6% for paved

drain field

a series of pipes in a septic system that are buried under gravel or crushed rock and are full of small holes that allow wastewater to flow into the gravel or rock

percolation test

a soil test designed to measure rate of water absorption and drainage such as for septic systems

n-year storm

the value of n is based on the probability that a storm of this magnitude will occur at this location in a given year

effect of louvers on air flow

they redirect and diffuse air

to protect against the cold winter winds

- avoid hilltops, north-facing slopes, narrow valley bottoms, and other locations exposed to the concentrated or fast-moving winds - identify direction of prevailing winds - avoid large north or wind facing glass areas

minimize heat loss

- strategize glazed openings - arrange secondary-use spaces within the building to act as buffers against north/windward sides -compact form

minimum sewer slope

.5-2%

surface drainage slopes

1.5% for grass 2-3% for pavement

slope for parking

1.5-5%

max flush of toilet

1.6 gallons

slope of finish grades

5% minimum to drain surface water away from a building 2% for impervious surfaces

constructed wetland

A wetland that is built, usually for the purpose of stormwater runoff management or wastewater management. Also called artificial wetland.

runoff coefficient

A number that indicates the portion of rainwater that will be discharged by a particular surface.

dry well

A pit, usually filled with coarse stone, into which water is conducted for leaching out into surrounding soil.

sanitary sewer

A sewer that conveys sewage but excludes storm, surface, and ground water.

catch basin

A sievelike device at the entrance to a storm sewer which traps matter that could block the sewer. They have a basin or sump that retains heavy sediment before it can pass into an underground drainpipe.

moment frame

A space frame in which members and joints are capable of resisting lateral forces by bending as well as along the axis of the members. Varying levels of resistance are provided by Ordinary, intermediate and spacial moment frames as defined in the NEHRP Provisions with Special Frames providing the most resistance.

Life Cycle Assessment

Analysis of environmental impacts of products from the design stage through end-of-life.

sidelighting

daylighting from sides of building, as provided by vertical windows in walls can provide illumination for depths up to approx 2.5 times the height of the opening above the plane of the work surface

graywater

Domestic wastewater composed of wash water from kitchen, bathroom, and laundry sinks, tubs, and washers. (EPA)

retention pond

designed to hold a specific amount of water indefinitely. Usually the pond is designed to have drainage leading to another location when the water level gets above the pond capacity, but still maintains a certain capacity

LEED

Leadership in Energy and Environmental Design 1. sustainable sites 2. water efficiency 3. energy and atmosphere 4. materials and resources 5. indoor environmental quality 6. innovation in design 7. regional priority

bundled tube

More than one tube, joined together, as in the Sears Tower (now Willis Tower)

vertical louvers

Most efficient on the east and west elevations.

subsurface drainage

Should be used on soils with slopes <6% that are somewhat poorly or poorly/very poorly drained. Consists of underground network of piping for conveying underground water to a point of disposal. Excess ground water can reduce the load-carrying capacity of foundation soil and increase the hydrostatic pressure on a building foundation.

Rainwater collection system

System composed of water collection, storage cistern, and a water distribution system

best climate for water features

dry climates, raise humidity

effect of slots in overhang on air flow

equalize external pressure of air flow

surface drainage

The grading and surfacing of a site in order to divert rain and other surface water into natural drainage patterns. A holding pond may be necessary when the amount of surface runoff exceeds the capacity of the storm sewer system.

invert

The lowest point of the inside of a drain, pipe, channel, or other liquid-carrying conduit.

lateral bracing

Usually diagonal bracing in the structure to counteract wind pressures. (ex. X or K brace)

bentonite

an aluminosilicate clay that swells in water and has powerful properties of adsorption use drilled piers to support building weight on bedrock or stable soil below

culvert

artificial channel for water; drain crossing under a road

four materials that must be handled by a certified contractor

asbestos lead PCBs (polychlorinated byphenyls) vermiculite

drift/lateral displacement

can damage exterior materials and cause discomfort at upper floors should be limited to 1/500 of the blgs height

bents

columns and beam lines designed to carry wind loads

evaporative cooling

hot, dry air passes through wetted pads or misted water in cooling towers located above the occupied portions of a building

climate most in need of wind

humid

fan-forced rock bed solar heating

hybrid of passive and active sunlight is brought directly into the inhabited spaces when interior temperature rises above comfort level, thermostat-controlled fans draw the overheated air through a large container of stones where excess heat is absorbed large, expensive better temp control

effect of roof overhang on air flow

increase air flow into the spaces

what effects wind

land masses and current directions

thermal mass design

must be located within the occupied areas of the bldg and situated in the direct path of the nighttime ventilation airflow

Energy Policy Act

provides policies for how different sources of energy are developed and used including oil and gas; tribal energy; nuclear matters; vehicles and motor fuels; hydrogen; hydropower and geothermal energy; and renewable energy.

fundamental period

the time it takes for the structure to complete one full swing from side to side

flat roofs

require either interior roof drains or scuppers along their perimeter for drainage secondary, emergency overflow roof drains or scuppers are required in cases where water might be trapped if the the primary drains are blocked in winter snow may act as insulation

steeply pitched roof

shed water quickly if the angle of the slope is greater than 60 deg. it may slough off snow

fastest mile wind

speed measured of a column of air 1 mile long that passes of a given point

trussed tube

system that uses a combination of rigid and diagonal braces on the exterior wall. each x braces spans 5-10 floors (John Hancock Bldg)

knee bracing

system that uses bracing struts that can be concealed within a ceiling system

framed tube

system that uses closely spaced exterior columns and beams that rigidly connected to form a very rigid and stiff form

portal frame

system that uses trusses at each floor level with knee braces. only used if trusses are also used to support the floor

wind shadow

the area near the bottom of the leeward side of a hill, where the wind velocity decreases to almost zero

resonant load

the building moves side to side perpendicular to the direction of the wind (oscillating load)

chord force

the force created by wind loading along a floor or roof producing compression and tension

gradient height

the height at which friction from the ground & other obstructions no longer affect the wind speed open country = 900 suburban = 1200 metro = 1500

toplighting

the integration of daylight into interiors by gathering light through the roof of a building

most difficult building orientation for daylight

toward the portions of the sky in which the sun is low in its daily path generally toward the east/west

mechanically assisted natural ventilation

uses powered fans to increase airflows through the bldg

groundwater

water that fills the cracks and spaces in underground soil and rock layers

windward roof slope

wind exerts positive pressure on windward roof surfaces have a slope greater than 30 degrees (exerts negative pressure or suction on sides and leeward surfaces on roof surfaces with less than 40 deg)

to ensure even light distribution

window openings should be at least half as wide as the length of the wall in which they are located