Site Flashcards
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?
Above ground drainage systems: previous paving, sheet flow, gutters, ground swells, channels.
Underground drainage systems: Perforated drain, enclosed storm swers, natural drainage outlet.
Sheet flow
Water that drains across a sloping surface, whether the surface is paved, grassy or otherwise landscaped.
Storm drain
Collect water from roof downspouts, catch basins, and drain tiles surrounding the building foundation.
Drain inlet
An opening in the ground that allows storm water to run directly into the storm sewer, the opening is usually covered with metal grate for safety to keep out debris.
Catch basin
An underground reservoir that has a sump built into it, debris settles into the sump instead of flowing Down the sewer and potentially clogging the pipes.
Spacing of manholes
Manhole Access are located wherever the sewer changes direction or a maximum of five hundred feet apart.
Runoff coefficient
Fraction if water not absorbed.
100 year storm
25 year storm
10 year storm
1% probability
4% probability
10% probability
Holding pond
Collects excess runoff that municipal storm sewer cannot accept, and releases it at a controlled rate.
Minimum slope of bldg sewer:
2%-5% depending on pipe sizing.
Greater slope is required for smaller pipe & vice-versa.
Maximum slope for a road:
15% for short distances but 10% or less is preferred.
Cross slope of a road:
1/4 inch per ft or 2%
Roadway gutter depth
6” deep
Sidewalk slopes
5% max running slope
2% min perpendicular slope
Curb cut ramp slopes
Access ramp 1:12 max (8%)
Sides 1:10 max (10%)
Stair reqirements
34-38 inches high
7” rise 11” run
Standard car stall
9’-0” x 19’-0”
Compact car stall
7’-6”x15’-0”
Most efficient parking layout
90° double loaded aisle (62’ stall to stall edge, 24’ aisle)
Parking SF per car
300-400
Typical ADA parking stall
8’-0”x19’-0” with 5’ aisle
Van ADA stall
8’-0” x 19’-0” with 8’ aisle
Drainage in parking area
1.5% - 5% (2%-3% typ)
Typical change in elevation at double loaded 90° parking
Max 3’
PUD
Planned Unit Development
External-load/skin-load dominated building
When a building’s energy use is determined mainly by the amount of heat loss or gain through its exterior envelope.
Internal-load dominated building
A building Whose energy use is driven by high heat gain from occupants, lighting, and equipment.
Building shape in cool & cold regions
Cubic
Building shape in temperate climates
Shape not as crucial, but oriented long axis east/west
Building shape in hot-arid region
Square with open courtyards for external heat loaded. Multistory for internal loaded building.
Building shape in hot-humid region
Elongated in east/west, with courtyards and overhangs.
Shading south facing facades
Overhangs or horizontal louvers
Shading east and west facing facades
Vertical louvers
Infiltration and exfiltration
The movement of air into and out of a building by natural means rather than through mechanical ventilation. Caused by differences in pressure between the indoor and outdoor air; these differences can be caused by a combination of wind, stack effect, mechanical system in the building, and other factors.
Stack effect
The difference in pressure between the top and bottom of a building due to temperature differential.
Air barrier
Part of a building envelope system that controls infiltration. It consists of materials, components, and assemblies on all vertical & horizontal surfaces exposed to the exterior.
Vapor-impermeable barrier
Acts as both an air barrier and a vapor retarder.
Vapor-permeable barrier
House wrap, polyethylene, elastomeric coatings, liquid-applied spray-on, or trowel on materials, etc.
Premience
A measure of how readily a material or membrane allows water vapor to pass through. The unit of permience is the perm, which is one gram of moisture per hour per square foot per inch of mercury difference in vapor pressure.
Minimum permeance of an air barrier
5 perms or greater
Appropriate soils for earth-sheltered designs
Gravel, sand, and sandy loam. Clay soils are not appropriate for earth-sheltered designs because they do not drain well and can expand with moisture.
Extensive green roofs
Soil is less than six inches deep. It is capable of supporting meadow grasses, sedums, herbs, and perennials.
Intensive green roofs
Soil depth Twelve inches or more and support complex landscapes, including shrubs and small trees.
EFVM
Electric field vector mapping.
A Waterproofing test for green roofs where the growing medium is wet to provide an electrically conductive layer and the deck is grounded. A leak will cause electric flow from the growing medium to the deck below.
SHGC
Solar heat gain coefficient.
The amount of solar radiation that is transmitted through the entire window assembly is expressed as a fraction of the total amount that strikes it.
A value of 1 means all solar radiation passes through, and 0 means none passes through.
Spectrally selective glazing
Transmits A high proportion of the visible solar spectrum while blocking up to 80% of the heat from the infrared portion of the spectrum.
Daylight factor
The ratio of illuminance at a point on a horizontal surface indoors to the aluminums at a point on the horizontal surface outdoors, measured at the same time under overcast skys.
Window to Wall Ratio (WWR)
The net glazing area in a room or space divided by the gross exterior wall area. Not inclusive of millions or frames.
VLT
Visible light transmittance.
The percentage of visible light that passes through a glazing material.
Direct gain systems
Collect heat through south facing glass and then store this heat in a high mass materials, such as concrete floors masonry walls tilesstone and terrazo.
GSHP
Ground source heat pumps are electrically powered systems that work like air source heat pumps by either extracting heat from the ground in winter or giving off excess heat to the ground in the summer.
Acidification
The generation of waste materials that can lower the ph of surrounding waterways or soil.
Eutrophication
The formation of excessive nutrients in a body of water that promotes increase algae growth.
Embodied energy
Energy used for extraction, processing, manufacturing, & transportation to the site.
Renewable materials
Materials sourced that can renew themselves in a short time through new growth.
Benefits of fly ash concrete admixtures
Increased concrete strength, decreased permeability, reduce temperature rise while pouring, increased sulfate resistance, and improved workability.
AAC
Autoclaved aerated concrete.
Lightweight, precast concrete made with aluminum powder as an extra ingredient. Hardened in molds and cured in an autoclave (steam filled pressure chamber).
Waterproofing
The control of water and moisture that is subject to hydrostatic pressure. It can refer to the application of water tight membranes, water stops, or bentonite panels when building below the water table.
Vertical Soldier Beams
A deep excavation would require the use of vertical soldier beams supporting horizontal timber breastboards or cribbing. The vertical soldier beams must be anchored into the adjacent Earth with grouted tieback rods. Even steel sheeting would require tiebacks for support.
Bentonite
Bentonite is an expansive type of clay that can push foundations and floor slabs upward when it gets wet. To prevent this, drilled piers are used to support the building weight on bedrock or stable soil below the bentonite. Grade beams span continuously between the piers and transmit building loads from the superstructure to the piers. Voids are left below the grade beams. To allow the bentonight to expand without transmitting uplift forces.
Caissons
Caisson foundations, also known as pier foundations, are prefabricated hollow substructures designed to be constructed on or near the surface of the ground, sunk to the desired depth and then filled with concrete, thus ultimately becoming an integral part of the permanent structure.
Retention Pond
A retention pond, also called a wet pond or a holding pond. Prevents excessive storm water run off on-site from overloading the storm sewer system by temporarily holding the excess water and releasing it at a controlled rate until the water has lowered to reach its designed holding level.
Bioswale
Site designed element to allow sediment to settle while water drains into the ground.
Infiltration basin
Site designed element that retains water until it can seep into the ground. Infiltration is the process of percolating storm water into the subsoil.
Runoff Coefficient
The fraction of total precipitation falling on a surface that runs off of the surface or is not absorbed into the ground.
The runoff coefficient is used to calculate the amount of runoff in cubic feet per second on a site.
Q=CIA
C= runoff coefficient
I = rainfall intensity
A = area of surface in acres
Natural Surveillance
Natural surveillance relates to the ability to see into and out of an area. It involves the placement of physical features, activities, and people in ways that maximize the ability to see what is occurring in a given space, and optimize the potential to spot suspicious persons or activities.
Territorial Reinforcement
Territorial Reinforcement isthe use of physical attributes that express ownership such as fencing, pavement treatments, signage, and landscaping.
Standoff Distance
The space between a building and the potential location of a blast threat. For blast protection, this distance should be maximized because blast energy decreases exponentially with increased distance between the source of the blast and the building.
Detention
The temporary storage of storm run off in a detention facility to control peak discharge rates and to provide gravity settling pollutants. The detention facility is designed to provide for a gradual release of stored water at a controlled rate.
Drainage easement
The legal right granted by a landowner to a grantee, commonly a governmental entity, allowing the use of private land for storm water management.
Effective aperture
The product of visible transmittance and the window-to-wall ratio.
Fee in lieu
Payment of money by developer in place of meeting, all or part of store water performance standards.
HSG
Hydraulic soil group
A classification of soils based on their potential for runoff when thoroughly wet. There are four groups ranging from Group A, which contains soil’s high and gravel and sand that have high probability and low runoff potential to Group D, Which contains clayey soils that have low permeability in high runoff potential.
Watercourse
Any body of water such as a lake, pond, river, or stream.
Waterway
A channel that directs surface run off to a water course or a public storm drain.
Swale
Natural or human-created low tract of land that is designed to manage stormwater runoff and provide a place to filter pollutants or trap particulates, allowing water to slow seep into the ground.
Stormwater pond
a basin that has a permanent pool of water. It differs from a swale or stormwater wetland in that it has a greater average depth and is covered with water all the time.
Wetland
An area that is inundated or saturated b surface water or groundwater at a frequency and duration sufficient to support, and that under normal circumstances does support, a prevalence of vegetation typically adapted for life in saturated soils.
Brownfield
A property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of hazardous substance, pollutant, or contaminant.
1 Acre equals how many SF?
43,560 SF
