Built form typomorphology

Typomorphological Study of Built Environments based on Density Measures YEN YU CHEN

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Contents Introduction Research framework Research design Results Conclusion

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Introduction

Source: http://cone.gollnerfire.com/wpcontent/uploads/2015/09/EMspecturm-600x266.jpg

Electromagnetic spectrum 3

Introduction

Source: Penn State

Spectral signature → Object identification 4

Introduction

Farmhouses Apartment building High-rise building

?

Terraced housing

Taichung City, Taiwan

Spectral signature → Building typology?

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Introduction

“When you see the particular, always look for the general” - Albrecht Penk

“Too much research is of purely local significance, failing to relate the particulars of individual places to a wider framework of thinking” - J. W. R. Whitehand

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Introduction

Density increases

High compactness

High building intensity

Low compactness

Low building intensity

Q: Is there a spectral signature for building types?

A: Yes, based on DENSITY 7

Introduction

TYPOLOGY

MORPHOLOGY

Building forms

Over-the-Rhine, Cincinnati

J.N.L. Durand, 1809

Daniel Brian Ferdelman, 1997

(ARCHICTECTURAL)

(GEOGRAPHICAL)

Introduction

TYPOMORPHOLOGY

• Phylogenesis • Evolution • Typology

• Ontogenesis • Development • Morphology

Introduction

Typomorphology • Dialectic between building typologies and urban morphology • Explain how the built environment is produced by classifying systematically the elements which structure the physical form of cities over time Morphology

TYPE

Habitus

Typomorphology

Typomorphological framework of the built environment in the making Adapted from Pierre Gauthier, 2004

Research framework

Aim and objectives

Research aim: To demonstrate a methodology for typomorphological studies of the built environment based on density measures.

Research objectives: 1.

2.

3.

4.

Review existing density measures and conceptual framework of typomorphology Investigation in solving the problems found in existing practices of density measures Demonstration and validation of proposed methodology Evaluation and interpretation of analysis results

Literature review

Research design

Implementation

Results Conclusion 11

Research design

Density in urban planning - Introduction of density regulations since late 19th century - Density as an ideological agenda of urban professionals - Density as an indispensable tool in shaping urban form

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Persons Per hectare

Howard Ebenezer’s Garden City

3500 Persons Per hectare

Le Corbusier’s Radiant City

850 Persons Per hectare

Jane Jacob’s Greenwich Village 12

Research design

Density in urbanism terms generally describes the relationship between a given area and the number of certain entities in that area. i.e.

Population density

Dwelling density

Floor area ratio

population hectare

dwelling units hectare

floor area site area

Open space ratio

open space area floor area

density =

mass volume

or in short form:

m d= v

}

under the premises that the measured substance is HOMOGENEOUS Young’s modulus – density chart

WORKING DEFINITION

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Research design

Problems of integrating density measures into typomorphology:

a city is anything but HOMOGENEOUS

1.Subjection to MAUP 2.Ambiguity of spatial unit 3.Poor reflection of urban form 4.Preconception of type

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Research design

1

Subjection to MAUP

40 dw/ha

• Many density measures describe a part-to-whole relationship • Often represented as ratios of some occupier as the numerator, and a defined unit of area as denominator

50 dw/ha

• Definition of denominator is ambiguous and flexible 60 dw/ha Source: Berghauser Pont and Haupt (2010)

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Research design

2

Ambiguity of spatial unit

• Hierarchy is essentially one of containment, a given disposition by the higher order to the lower • Contributive vs Resultant form • The potentiality of the building is contained within the plot, and contrarily the plot is dispositive of the resultant building(s)

Source: Berghauser Pont and Haupt (2010) 16

Research design

Solution to problems 1 and 2

Plot as spatial unit of analysis Plot

Building type

(contributive form)

(resultant form)

Problematic scenarios Possible solutions Plot redrawn to resultant perimeter of combined plots

(1) Single plot consisting of multiple buildings of different building type; (2) Single building covering multiple plots; (3) Multiple buildings of different building type covering multiple plots.

Divide buildings according to intersecting plot boundaries

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Research design

3

Poor reflection of urban form

• Density measures has been criticized explicitly for its descriptive weakness of physical/spatial properties of urban form • The same density can be obtained with radically different building types, and the same type can be used to obtain different densities

75 dwellings per hectare

75 dwellings per hectare

75 dwellings per hectare

Identical FAR with different form

Source: Berghauser Pont and Haupt (2010) 18

Research design

Solutions to problem 3

Multivariate density measures • Ground Space Index (GSI) reflects compactness of development

• Floor Space Index (FSI) reflects building intensity

• Building height (L) average number of storeys of building(s)

• Open Space Ratio (OSR) indicates pressure of developed floor area on non-built space Building type clusters on Spacemate diagram M. Berghauser Pont, P. Haupt TU Delft 19

Research design

Solutions to problem 3

Linear programming / kernel density estimation • Enhances statistical profiling • Demarcation of cluster boundary • Identification of archetype

Concept of linear programming on Spacemate

Kernel density estimation of building type cluster 20

Research design

4

Preconception of type

• As type and typology concerning the built environment is convincingly cultural products, there can be no unifying or definitive way of classification • Generalization bears the latent danger in stereotyping that may blind us from seeing the emergent.

• “To observe, then, is to be content with seeing a few things systematically” – Foucault

pavilion

street

court

Source: Martin and March (1972) 21

Research design

Solution to problem 4

Exploratory clustering analysis Two-step clustering analysis

FSI

• Handles large datasets • Automatic determination of clusters

Clustering dendogram

Two-step clustering result on Spacemate

GSI

Clustering scree plot

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Research design

Study area

Base data

Taichung City, Taiwan Population: 2.7 million Area: 2,215 km²

Building footprint and parcel map of Taichung City, 2001

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Research design

Data cleaning

Data formulation

After exclusion of insignificant building structures, 234,820 building objects remain

Calculation of density measures CA

After merging of plots, 91,137 parcel objects remain

Cleaning off building extensions

Redrawing plot boundary

Formulated attribute table 24

Research design

Data analysis Explorative data analysis • • • •

Deduction of correlation between density measures Automatic determination of building type clusters Delimiting the density conditions of each building typology Interpolation of archetype and deviation for each building type

Empirical data analysis • • •

Semantic translation of discovered building typologies Identification of real-world examples Cross-referencing results with land use plan 25

Results

Interpreting density measures Descriptive statistics for density measure of Taichung City

Descriptive statistics of density measures provides an initial outlook on the spatial structure of Taichung City

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Results

Comparative study with Manhattan Descriptive statistics for density measure of Manhattan

Descriptive statistics for density measure of Taichung City

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Results

Spectral signature of building types Type 2

Type 3 Type 4

Type 5

Type 6

Type 7

Type 8 Type 1

Type 9

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Results

Spectral signature of building types

Low intensity building types

Moderate intensity building types

High intensity building types

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OSR(min) = 0.00

Results

Typological process

③

FSI(max)② = 8.48

• Demonstrate variation between archetype and deviations within typologies

+

GSI(min) = 0.46

①

①

③ GSI(max) = 0.99

② FSI(min) = 3.59

① Deviation (min)

② Archetype

③ Deviation (max)

• Understanding the conditions and context of typological changes • Reflection of social demands 30

Results

Typological process

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Results

Co-occurrence of densities Bivariate correlation of density measures GSI, FSI, OSR, and L

Implications of building coverage

Implications of building height

Scatterplot matrix of GSI, FSI, OSR, and L 32

Results

Typological outliers

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Results

Typological discontinuity • Building Act of Taiwan requires buildings higher than 6 storeys tall be equipped with elevators • Buildings will leapfrong from 5 storeys to 11 storeys high, skipping the height in between all together • Makes sense economically to minimize marginal cost of elevator installation by building higher till a point of desired profitability 34

Results

Spatial density distribution of building types

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Results

Spatial density distribution of building types

Land use map of Taichung City

Spatial distribution of Type 4 (high-rise buildings)

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Results

Revision of urban theories

Transect planning Duany and Talen, 2002 37

Conclusion

The proposed methodology provides: 1.

2.

3.

4.

5.

High level of spatial resolution by using parcel as the unit for analysis Multivariate in the description of built form through density measures Exploratory and non-stereotypical in the classification of building types Systematic in the statistical and semantic profiling of discovered types Explanatory of emergent spatial structures Correlation between density measures

Density profile of cities

Density spectrum for classifying building typologies

Spatial distribution of building types 38

Results

Limitations

FSI

• Requires parcel data, which may be hard to acquire • Clustering results are highly reliant on the quality of dataset • Results of kernel density estimation varies with different search bandwidths

Parcel data

Clustering results

GSI

Kernel density bandwidth 39

Results

Future work • Automization of the methodology into an analysis tool • Spatial-temporary analysis of the evolution and morphology of building types

Gapminder http://www.gapminder.org/

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THANK YOU FOR LISTENING Typomorphological study of built environments based on density measures YEN YU CHEN Advisor: LIN HAN LIANG

Master’s thesis presentation, 26 June 2015 Department of Urban Planning, National Cheng Kung University 41