Building Context Flashcards
Expanding Grid
Type of development pattern starting at intersection of 2 major roads. Laid out on grid. Ex: Philly
Star Pattern
Type of development pattern where development follows radiating spokes of major highways / transportation from dense core.
-High density along spokes
-Low density b/t spokes
Ex: Chicago
Satellite Pattern
Type of development pattern where large dense urban core is surrounded by major urban areas.
-satellites linked to core by highways
-satellites linked to themselves by beltway
Ex: Houston
Field Pattern
Type of development pattern with no central focus or organization.
-amorphous network of highways / natural features
Ex: LA
Megalopolis
Type of development pattern where 2 or more large urban areas grow together.
-ultimate form of urban development
Ex: LA
Imageability
quality of physical environment evokes strong mental image
What are 5 basic elements of imageability?
- Paths (circulation)
- Edges (linear element, boundary b/t areas - can be path)
- Districts (identifying character separate from city)
- Nodes (point of reference - can be entered)
- Landmarks (point of reference viewed from exterior)
Edge
Element of imageability
-linear element / boundary
-can also be path
Ex: Buildings around Central Park create boundary around park
District
Element of imageability; area / neighborhood with identifying characteristic separate from city.
Ex: Georgetown in DC
Node
Element of imageability; focal point that people can enter.
Ex: Plaza or public square
Landmark
Element of imageability; point of reference viewed from exterior.
-may or may not be entered
Ex: Washington Monument
Superblock
Large piece of land with limited intrusion.
-minimize impact of car on housing
-development of park space within block
Ex: NYCHA
PUD (Planned Unit Development)
Large parcel of land with mixed uses
- variety of lot sizes / densities
- standards determined by local planning agency
- efficient use of land
- extra land used for public / open spaces
- variety of housing options
- group compatible uses without regulation of zoning setbacks
What are 6 standards of PUDs?
- Permitted uses
- FAR
- Amount of open space
- # of / configuration of parking spaces
- Max. Bldg heights
- Required setbacks & proximity of structures
Density
Number of people per area.
-does not indicate how people are distributed
FAR
Floor area ratio (ratio of developed floor space to land area)
Sociopetal
Bring people together
Sociofugal
Discourage social interaction
What are the 4 types of personal space?
- Intimate (6”-18”)
- Personal (1.5’-2’)
- Social (4’-12’)
- Public (>12’)
Catchment Area
Geographical region a population resides in that affects land development.
-physical or artificial boundary lines
-knowing gross population not enough; need to understand composition
Ex: School district for a particular school building
Neighborhood
Relatively small area in which a number of people live & share similar needs in housing, social & other aspects of daily living.
Public Facilities
Places like schools, shops, fire stations, places of worship etc.
-location & availability can affect how site is developed
Proxemics
Deals with issues of spacing between people, territoriality, organization of space & placing people within space.
Behavior Setting
Place with defined boundaries in which standard pattern of behavior occurs at a particular time
Ex: weekly meeting in a conference room
Territoriality
Need to lay claim to spaces we occupy & things we own
-applies to groups & individuals
Name the 4 types of roads
- Local
- Collector
- Arterial
- Expressways
Local Street
Low capacity, provides direct access to site
- can be continuous grid or curvilinear in form or cul-de-sacs / loops
- parking often available
- connects to pedestrian circulation system
Connector Street
Connects local streets with larger arterial streets.
- higher capacity but not intended for thru traffic
- intersections controlled by stop signs
Arterial Street
Major, continuous circulation route that carries large amounts of traffic on two or three lanes.
- connect collector streets to expressways
- intersections controlled by stop lights
- parking not allowed
- direct access to site should be avoided
Expressway
Limited access roads designed to move large amounts of traffic between, through, and around population centers.
- intersections = various types of ramps
- no pedestrian access
- major influence on land (noise & size)
Tangent
Straight section of road
Service Access
Can include provisions for truck unloading, moving vans, deliveries.
- ideally separate from vehicular & pedestrian access
- loading berths b/t 10-12’ long, 40’ deep, 14’ tall
- min. turning radius of 60’
Easement
Privately owned land that utility companies have access to
When developing a site, what new service location is most important?
Sanitary / sewer because it relies on flow of gravity & depends on natural slope of site
Macroclimate
Overall climate of a region.
-Region can be classified as cool, temperate, hot-arid or hot-humid
Microclimate
Site specific modification of macroclimate by features such as land slope, trees / vegetation, bodies of water,and buildings.
How can trees planted in a group 50-150 deep modify wind patterns?
Reduce wind velocity from 30-60% depending on density of trees at a density 10x the tree height.
Where is wind speed the highest on a hill?
On the top of the hill (can be 20% higher than at the bottom)
Inversion
Weather pattern in which colder air near the ground is held in place by the warmer air above it, trapping dust & pollution
Albedo
Fraction of radiant energy reflected from a surface.
- also called solar reflectance
- higher reflectivity = higher albedo
- measured on scale from 0-1.0
What types of materials have lower albedos?
Natural materials such as vegetation, grass
What materials have higher albedos?
Snow & pavement
Reflectivity
In LEED rating system its used to measure solar heat rejection of non-roofing materials such as vegetation, shading devices & other less reflective components.
Emissivity
Ability of surface to emit stored energy
-Thermal emittance is similar measure of solar radiation
Solar Reflectance Index (SRI)
Measure of a roof’s ability to reject solar heat.
- standard black surface has SRI of zero
- standard white surface has SRI of 100
Heat Island Effect
Unnatural buildup of heat around buildings
How do you mitigate heat island effect?
Use materials with the highest SRI & SR (these will be the coolest materials)
-Can also plant trees & specify open-grid paving
Is it better to use high albedo materials or vegetation to reduce heat island effect?
When practical, vegetation is preferred because it retains less heat, more comfortable underfoot, & reduces storm water runoff
What are some high albedo materials?
Light colored concrete
What are maximum grade ranges for most streets?
3%-10%
What directional axis is best for locating a building so that it takes advantage of solar heat & light?
East-West
What benefits do trees, shrubs & groundcover provide to a site?
- Mitigate winds
- Absorb runoff
- Lower albedo
- Absorb noise
- Humidify air
- Provide shading, reduce heat island effect
What plants are best to mitigate winds, block views, or provide privacy?
Evergreen trees
When evaluating a site, what is one of the most valuable assets?
Presence of natural water
What is first consideration when evaluating a site if water exists on site?
Limit potential for run-off from building & site improvements such as parking lots
What are concerns when evaluating development of site in rural or semi-rural areas?
Potential impact on natural landforms, water runoff, wildlife, & existing vegetation.
- dev. Should disturb natural contours of site as little as possible
- existing drainage patterns must be left in tact
- additional runoff should not exceed capacity of existing drainage facilities
What are concerns when evaluating development site in an urban area?
- Minimize noise
- Minimize pollution
- Avoid creating undesirable wind conditions
- Minimize blocking sunlight
Understand impact on utilities & transp. systems
Wetland
Area whose soil is saturated by surface or ground water frequently enough that it can support plants that can live in saturated soil.
-Protected by Federal govt
What are sustainability issues to consider when analyzing a site?
- Portions of site not suitable for development
- wetlands, areas w/in 100 ft of wetlands etc. - Historical / Cultural qualities of surrounding area
- Future developments that may surround site
- Existing air quality
- Have soil / groundwater tested for contamination
- Determine presence of endangered species
Infiltration basin
Closed depression in the earth from which water can escape only into the soil
Catch basin
An area that temporarily contains excess runoff until it can flow at a controlled rate into the storm sewer system
