Site Planning Basics

Site Planning Basics

• Site planning involves arranging structures and shaping spaces on land while linking land uses to architecture, engineering, landscape architecture, and city planning.
• According to Kevin Lynch in 1990, site plans locate objects and activities in space and time, ranging from small house clusters to extensive communities
• According to Harvey M. Rubenstein in 1996, site planning organizes land portions by detailing, analyzing sites, forming land use plans, managing circulation, developing visual form, and ensuring proper drainage.

Related Professions

• Landscape architects professionally execute site planning, though architects, urban/regional planners, and engineers are also involved.
• A landscape architect leads a team of architects, engineers, planners, and scientist-advisors on larger projects

Objectives of Site Planning

• Objectives include harmonizing design programs with sites, balancing natural, socio-economic, and technological factors, and understanding site development through natural/human factors.
• Additional steps consist of collecting/analyzing data, making recommendations, and creating guidelines for planning, architecture, and landscape disciplines

History and Basic Principles of Site Planning

• Four basic models exist: fixing the place, defining the enclosure, creating a sense of order, and forming an axis
• Fixing the Place The image/form of a building can fix a place
• Defining the Enclosure Independent structures create a coherent image.
• Sense of Order A building’s form can fix a place by enclosing facades.
• Form of Axial Contradictory paths can form coherent images.

The Process of Site Design

• Site design is a three-step process: research, analysis, and synthesis.
• The process includes programming, site selection, inventory of the site, analysis, conceptual design, design and construction development, documentation, and project implementation.

Methods of Establishing a Site

• Site selection process involves selecting the best site for the project. Requirements include specific site use.
• A development suitability process is used to help choose the best possible use and development for a given site.

Factors Influencing Site Selection and Resource Analysis

• Natural factors for site selection and resource analysis considers geology, geomorphology (landforms, soils, drainage, topography), and hydrology
• Also to consider: vegetation, wildlife, and climate (solar orientation, wind, humidity)

Cultural Factors

• Existing land use (ownership, nuisances), traffic/transit patterns in the surrounding area, and density/zoning regulations are all cultural considerations
• Socioeconomic factors including population density, literacy, sex ratio, occupation pattern, ethnicity, and cultural typology are to be considered
• Important to consider: The availability of utilities (water/sewage, power, water), and historic buildings/landmarks are cultural inputs

Aesthetic Factors

• Aesthetics considers natural environment, spatial patterns, views and vistas.

Natural Factors: Geology

• Geology is the natural science studying the Earth, its composition, surface processes, and history.
• Earth largely consists of rocks: igneous, sedimentary, and metamorphic.

Geomorphology

• Geomorphology is the study of landforms, including their origin, nature, and distribution.
• Also to consider: soil properties, drainage, topography, slopes, and soil erosion.
• Physiography describes landforms, while landforms are irregularities on the surface caused by various processes.

Geomorphology: Soil Properties

• Soil surveys guide site selection for residential, industrial, etc.
• Soil makeup (minerals, organic matter, water, and air) and texture are considered
• Soil properties are crucial for determining slope stability, bearing capacity, internal drainage, and erodibility.

Geomorphology: Drainage

• Good Drainage*
• Good drainage is the soil's ability to move gravity water through infiltration, permeability, and percolation
• Infiltration rates measure how quickly water enters soil, measured in in cm or inches per hour.
• Permeability rates measure how quickly water moves in soil, measured in in cm or inches per hour.
• Percolation rates measure the rate that water is absorbed in soil, measured in in cm or inches per hour.
• Poor Drainage*
• Poor drainage occurs when gravity water transmits slowly with soils frequently/permanently saturated. Is caused/indicated by:
• Local water accumulation
• High groundwater levels
• Small soil particle size not suited for infilitration

Geomorphology: Topography and Slopes

• Slope measures the steepness, expressed using gradient, grade, incline, and pitch.
• Site design requires understanding soil, geologic, hydrologic, vegetative and local conditions.
• Detectable contour maps are made up of four basic forms.
• A topographic map describes Earth's terrain with contour lines.
• Contours join points of equal elevation, enabling the measurements of height and slope steepness.
• Angle of Repose is the angle which all soil can be safely inclined before failing

Geomorphology: Soil Erosion

• Soil erosion occurs when rocks break down by wind, water, ice, and gravity, using gravitational/solar energy.
• Erosion rates depend on vegetation, soil type, slope/inclination, and rainfall frequency/intensity.

Hydrology

• Hydrology is the science of Earth's water, including properties, distribution, and its relation to living things.
• The hydrologic cycle is the movement of water from the ocean, to the atmosphere, then to the continents
• The water table distinguishes the boundry between the surface and the ground

Hydrology Key Terms

• Aquifer: A geological formation permeable to store/transmit groundwater.
• Watershed: Land area where topography captures and drains water to a shared destination.

Resources from Vegetation

• Use in climatic control
• Promotes environmental engineering
• And is useful for architecture + aesthetics

Vegetation: Impact on Climate Control

• Solar radiation warms the earth's surface and causes glare
• Trees control direct radiation because can block or filter sunlight, and improve natural air conditioning
• Plants help control precipitation and protect against erosion
• Trees help buffer winds caused by the effects of Venturi and convection in urban areas.

Vegetation: Environmental Engineering Properties

• Plants use photosynthesis to purify air; they absorb carbon dioxide and pollutants and produce oxygen
• Plants can absorb, reflect, or deflect sound as they are absorbent, reflective and deflective
• Plants minimize sun glare through density, shape, and foliage.
• Plants prevent erosion with water runoff with their route systems and vegetation provide slope stability

Vegetation: Architechtural Significance

• Plants define space and double up as ground cover for plane surfaces
• Plants enable view control and can be used to provide backdrops for structures
• Mood can be affected by plantlife

Wildlife

• Habitat elements essential to species of wildlife: open land, woodland, and wetland

Climate

• The climate is atmospheric condition over a long time, determining climatic classifications (Cold, warm arid, warm humid) and what solar orientation is appropriate for the buildings
• To asses: what are teh heat facing slopes and wind flows of the site

Solar Orientation for Buildings

• Orientation depends on the sunlight falling at different times.
• Clustering buildings optimizes heat absorption and shading.
• Lengthier building sides should face north and south.

Best Facing Slopes

• Temperatures decrease between 3-5 degrees for each increase of 1000ft In elevation.
• The more perpendicular a slope is to the rays of the sun, the warmer the surface temperature

Wind Flow

• Abrupt forms in design cause unpleasant air turbulence, and smooth shapes induce smooth flow of air.

Cultural Factors: Land Use

• Land Use Plans categorize areas and indicate available services.

Traffic and Transit Systems

• System must ensure that the relationship of the traffic patterns are adequate between both site access and area circulation
• Efficient transportation integrates with area developements
• The visual impact depends on if direction of traffic is from pedestrian vs vehicular
• Need to accommodate pedestrian flow

Density and Zoning

• Density is the ratio of land population, and is used to asses sustained development support
• Density may be measured via number of hectares
• Land and ordinances are required by city zoning regulations for development
• Regulations dictate building height, build coverage, population density, and open space.

Socio-Economic Factors

• Social + economic structures are studied to assess what kind of project is needed/desirable/acceptable
• Proposed projects must work in concert with local communities
• Local social structures must be preserved to ensure zero displacement

Utilities and Services

• To decide the current usability, existing utilities on site in must assessed
• To check for:
  • Electrical power
  • Sanitary systems
  • Water supply
  • Sewage

Historic Factors

• Preservation of historic landmarks
• Preservation of historic buildings

Aesthetic Factors

• To examine natural landscape in land
• And to consider: spatial pattern. View and Vista also to be understood.

Natural Features

• Assets of the land/site that can be built upon

Spatial Patterns

• The organization of open space is configured based on intended activity or stream

Visual Resources

• View* A scene observed from a vantadge
• Vista* To see through confined view, usually to a terminal or feature