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CONFERENCE: Obsolescence and Renovation – 20th century housing in the new millennium CONGRESO: Obsolescencia y Regeneración – viviendas del siglo xx en el nuevo milenio

Architecture_MPS; Universidad de Sevilla, Spain: 14—15 December, 2015

PERCEIVING SOCIAL HOUSING THROUGH MATRIX STRUCTURAL ANALYSIS - A THRESHOLD BETWEEN

THEORETICAL RESEARCH AND PRACTICAL APPLICATIONS

Authors: DOAA SALAHELDIN ISMAIL ELSAYED, WALAA S.E. ISMAEEL Institutions: POLITECNICO DI MILANO, ITALY; BRITISH UNIVERSITY IN EGYPT (BUE)

ABSTRACT The current adopted research methods for rehabilitation of social housing projects face lots of

challenges to address the complexity of socio-cultural, environmental and economic aspects. Hence,

the research discusses matrix structural analysis method that aims at bridging the gap between

theoretical and practical approaches for more sustained social housing rehabilitation projects. It acts as

a simplified analytical and decision making tool that is capable of structuring the huge range of data,

categorized into various scales; starting from urban to architectural solutions, and scopes; discussing

building energy performance and management process. The research applies the proposed matrix on a

case study project entitled: Interventions in Obsolete Residential Neighbourhoods: Manual of Best

Practices (ORRN-MBP) (Promoted by Junta Andalusia, University of Seville, Spain). The project

studied eight neighbourhood plans built between the 1950 and 1970 with potential cultural values but

suffering incompatibility with contemporary users’ demands. The proposed matrix presents a

comprehensive toolkit for decision makers and set a datum for sustainable social housing

rehabilitation plans.

Keywords: Matrix structural analysis, decision making process, social housing rehabilitation projects

INTRODUCTION

Rehabilitation of social housing projects is considered among the main challenges that face

preserving cultural heritage neighbourhoods especially due to the increasing incompatibility of

existing buildings to respond to contemporary users’ needs, demands and life styles. The research

presents a review of literature that discusses the definition and evolution of a matrix in urban and

architecture research arena. Then, it discusses obsolescence and rehabilitation of social housing

projects. The research method cites a case study in Seville, Spain for eight defined neighbourhoods to

develop the proposed matrix structural analysis and decision making tool in order to bridge the gap

between theoretical approach and practical application for dealing with rehabilitation of social housing

projects.

REVIEW OF LITERATURE

Matrix structural analysis has been used as an analytical tool to demonstrate interrelationships and

dependencies between elements to provide insights into how to manage complex systems or projects.

Then, it has evolved to be used as a decision making tool by weighing up and scoring different factors.



Matrix as an Analytical tool

The research uses two terminologies to describe a matrix as an analytical tool. First; ‘Matrix’ can be

perceived as a sort of an ‘Assemblage’ combining together different elements within certain bonds and

frameworks, and it could be composed of fragments of different times and scales aiming at

interpreting an identified message. It embodies a field of interrelationships concerning dependent and

independent variables, explaining connections between them. From this perspective, it has been used

on the urban analysis scale by Giovanni Battista Piranesi within his scenography of Campi Martii,

Rome, 1762. Also, Aldo Rossi used this method in his Analogous city collage (Venice Biennale in

1976).

Matrix can also be perceived also as a ‘Threshold’, in the sense of acting as a gateway or an interface

separating two fixed principals to introduce a new way, direction, principle and idea. Hence, it can be

considered as a powerful interpretive tool and analytical method that Leads experimental

transformations for different scales and scopes of problem solving to increase the capability to build

up a critical comparative analysis for the problem and proposals.

Matrix Structural Analysis is not a new methodological technique, where the term was introduced

within the scientific discourse in the early 20th century when Werner Heisenberg formulated the

theory of Matrix Mechanics. Also, Jean-Nicolas-Louis Durand used the method on the building

analysis scale in the late 18th and early 19th century, in order to systematise architectural knowledge,

and form a kind of “typological atlas of architecture”1

Matrix as a decision making tool

The transformations of the social structure and the need for mass production for housing after the first

and second post-war eras, focused on the production process itself to find a model suitable for social

housing, determined by new standards for housing to ensure existence of minimum occupants’ needs

in relation to low costs. Hence, this context fostered the use of matrix not only for structural analysis

but also as a decision making tool that could rule the housing construction process. 2

Alexander Klein, in 1928 used matrix of successive increments to describe an analytical

comparison for different typologies of social housing projects, followed by a numerical analysis using

the scoring method, then a graphical expression of spaces, relations and connections..Klien’s research

was a threshold that introduced afterword a series of experimental applications, e.g. the Gross-

Siedlung at Bad Dürrenberg housing project in Leipzig in 1930 for 1000 lodgings between Loggia

house typology, apartment blocks, and single family houses.

During the 1960’s, new challenges faced social housing projects to plan for the dynamics of growth

practiced in the informal slums. This promoted the project of PREVI (Proyecto Experimental de

Vivienda in Lima, Latin America) 3

as a pioneering housing project that aimed at creating low-rise,

high-density housing of 1,500 dwellings with a view to expansion and adaptation for each residential

unit. Later, a research work entitled ‘Time builds’ elaborated by 4 EquipoArquitectura (EqA),

Fernando Garcia-Huidoboro, Diego Torres Torriti, Nicolas Tugas, had been concluded with a final

matrix charting the lifespans and modifications of 14 housing models over forty years. This frame

work had been the main idea of the Chilean practice Elemental's "half a house" model.

Hence, the research develops a synthesis for using matrix as an analytical & decision making tool for

building design optimization and rehabilitation of social housing projects as shown in Figure (1).



Figure 1 showing time line evolution for using matrix as an analytical and decision making tool for social housing projects

Obsolescence and rehabilitation of social housing projects Political strategies for housing renovation policies in European countries are changing to emphasise

the following sustainable issues; (1) improvement of physical performance, (2) correspondence to the

needs of the elderly, (3) improvement of energy efficiency and, (4) social cohesion and area

revitalization, Baek and Park (2012)5. The study shows that comparing Spain to other European

countries, shows that it has relatively low ratio of house renovation investment occupied in total

houses (30.4%), while it has a medium ratio of public housing support in percent of state budge.

Obsolescence indicators

Obsolescence results from the factor of time, which implies change and most often degradation of

performance, usability, occupant satisfaction and the end of the service life of built facilities6

7, and

also due to the mismanagement of the physical assets of social housing over time. Obsolescence

presents a serious threat to the built property as it rarely accounts for its societal and cultural

significance. Hence, minimizing obsolescence and extending building life cycle by improvement,

renovation and renewal is a better and more sustainable solution8. This requires a systematic analytical

and predictive model for identification, prevention, diagnosis and cure of obsolescence indicators 9.

Different kinds of obsolescence can be classified, characterized and distinguished according to a

variety of theoretical/conceptual models. A study by Thomson and Flier (2011)10

and GOETZ (2012)11

classified them into physical factors (related to material processes) and behavioural factors (related to

human actions) and the interactions between them12

. Then, numerical methods can be developed to

measure/evaluate degradation in the physical and socioeconomic context. This also calls for

developing appropriate life cycle management plans to consider the building’s spatial and structural

flexibility to accommodate future changes13. Synergy arises from economies of scale when sites are

combined to increase their development potential.



Sustainable rehabilitation indicators

Rehabilitation addresses obsolescence of a building in its existing use. Strategic approaches for

rehabilitation may include: restructuring, diversification and regeneration14

. Sustainability and more

particularly energy efficiency, is a new (additional) input and has become a growing importance for

the market position of the built property15

. It includes social, economic and physical rehabilitation.

Hence, a recent study by Vehbi and Hoskara, (2009) proposed a model for measuring the

sustainability level of historic urban quarters and to indicate an appropriate strategy for their

rehabilitation. It introduces the characteristics, role, selection process and scaling method of

sustainability indicators, which are numerical tools used to measure changes in the physical, economic

and social structures of a defined urban area. It also shows an inversely proportional relationship

between type and the level of obsolescence (revitalization) and the level of sustainability in the

physical, economic and social structures of a particular area.16

METHODS

MBP project for Rehabilitation of Social housing neighbourhoods

The research presents the practical application of comparative matrix that took place as a concluding

frame work for the IORN-MBP project (Intervencion en Barriadas Residenciales Obsoletas: Manual

De Buenas Practicas), Junta Andalusia, University of Seville-Spain. The project aimed at studying the

current situation of the social housing neighbourhoods built between 1950 and 1970, which were built

following the recommendations of the Athens Charter at the end of the Franco dictatorship,

responding to a high demand for housing and addressing issues related more to quantity rather than

quality. The project defined Eight neighborhoods as shown in Figure (2), and discussed their measures

of obsolescence in order to propose strategies for rehabilitation plans in the form of Manual of best

Practices.

Figure 2 shows geographical location of the eight neighbourhoods under study

Indicators of obsolescence

The IORN-MBP project defined a set of weighted obsolescence indicators divided into physical

indicators (70%), and socio economic indicators (30%).

The project defined seven physical indicators for obsolescence and assigned weighting for each to

express different ranges of obsolescence from a total 70 points as shown in Table (1). Hence, by

comparing the obsolescence indicators for the eight predefined locations as shown in Figure (3), it is



shown that most neighbourhoods are suffering from problems in building accessibility, while least

problems occur due to urban complexity and public transport.

Table 1- physical obsolescence indicators and their weighting, IORN-MBP project

Accessibility of open spaces Possibility of use of EL Public transport coverage Coverage of equipments Urban complexity Building condition Buildings accessibilty Total

10 10 5 5 10 20 10 70

14.29 14.29 7.14 7.14 14.29 28.57 14.29 100.00

Figure 3 Comparing the physical obsolescence indicators for the eight neighborhoods.

Also, the IORN-MBP project defined six socio economic indicators of obsolescence with equal

weighting, as shown in Table (2). By comparing the eight neighbourhoods as shown in Figure (4), it is

shown that most socio economic obsolescence indicators are education level, population age and price

of housing unit.

Table 2 Socioeconomic obsolescence indicators and their weighting, IORN-MBP project

Empty units Occupation Population age Immigration Education level Price of housing unit

5 5 5 5 5 5 30

16.7 16.7 16.7 16.7 16.7 16.7 100.0

Figure 4 comparing the socio economic obsolescence indicators for the eight neighborhoods.

Then, the IORN-MBP project used logos to provide recommendations for the studied area as shown in

Table (3), and provided interpretations which combine together the previous three phases in a

comprehensive diagrammatic design.



Table 3 Using Logos to indicate recommendations, IORN-MBP project

IORN- MBP matrix representation

The IORN- MBP is represented as shown in Figure (5);



Figure 5 The IORN-MBP matrix for Poligono del Valle-01



Matrix structural analysis

The research develops a structural analysis matrix that demonstrates the composition of elements in a

legible and structured manner. The matrix is structured over an orthogonal grid to express the relation

regarding scales and scopes of action on the vertical axis, while sequential steps of structural analysis

and decision making process are expressed on the horizontal axis. The language used resembles an

assemblage of hybrid cultural, social and physical conditions. It varies according to the data

composition in the form of maps, photos, numerical charts, written texts, logos and illustrative

diagrams. In order to make an in sighted decision, matrix should demonstrate the following points:

criteria of assessment, options or alternatives, weights assigned to each criterion based on its

importance in the final decision, and scores used to rate each option on a ratio scale.

Matrix Scales of action

Sustainable rehabilitation plans require defining a scale of action which facilitates setting targets and

defining appropriate indicators for obsolescence and sustainability. The matrix defines two scales of

action which are the ‘Urban scale’ and the ‘Building scale’.

The Urban scale

Urban Analysis takes two steps; documentation and defining obsolescence indicators. Documentation

requires gathering general data related to geographical location, urban and housing housing patterns,

connectivity, public transportation and land-uses, and then determining the preservation value for the

urban context and the development dynamics status and rate. While, obsolescence indicators are

defined according to problems of connectivity and accessibility of urban pattern (e.g. Chana and

Bami), lack of mixed uses and recreational areas, scarcity of street furniture, and shortage of public

transportation.

Decision making process takes two steps; ‘Recommendations’ for sustainable rehabilitation, and

‘Interpretation’ for strategic action plans. Sustainability indicators focus on 7 aspects that include the

following; compactness, connectivity, inclusiveness, green, multifunctionality, creativity and safety as

shown in Figure (6). Finally, the research uses the classification of strategic approaches found in

Vehbi and Hoskara (2009)17 to define levels of action for the urban scale and accordingly its time

plan and output. The shortest interference level is ‘functional restructuring' with immediate physical

output, then promoting ‘functional diversification’, and finally when the neighbour is self-sustained

and begins its role as a regeneration agent within its community-‘functional regeneration’- this

requires the longest time plan and provides both physical and socio economic outputs as well.

Figure 6 Functional regeneration plan for Poligono del Valle-01, IORN-MBP project



The Building scale

Building analysis takes two steps; documentation and defining obsolescence indicators.

Documentation requires gathering general data related to building heights, condition, construction type

and year, ownership type, occupants’ density, ages and needs. Obsolescence indicators are related to

limited housing typological diversities, incompatibility of housing unit vertical circulation facilities,

dimensions and distribution with occupants’ current needs.


‘Interpretation’ for strategic action plans. Sustainable indicators focus on 6 aspects; attractiveness of

social housing typologies, diversity of mixed land uses, accessibility, flexibility, and safety. The

research uses the classification of housing rehabilitation strategies proposed by Baek and Park (2012)

into extension type, individual type, combined type and integrated type depending on the rehabilitation

objectives and house characteristics as shown in Figure (7). Time plan and economies vary according

to the type of adopted strategy with the least budget for the combined and integration plans so as to

benefit from the economies of scale, while the most expensive are the individual and extension plans

where each building unit is discussed individually.

Individual type rehabilitation plan

Extension type rehabilitation plan

Combination type rehabilitation plan Integration type rehabilitation plan

Figure 7 Building scale- rehabilitation plan to solve the problem of improving vertical circulation,

author’s elaboration after IORN-MBP project



Matrix Scopes of action

The matrix defines two scopes of further action related to the ‘Management’ and ‘Energy’. The term

management can include variety of scopes. Yet, the IORN-MBP project focused on assessing and

improving social, community and shared management process, and on the energy performance of the

building envelope.

Sustainable Management indicators

Management analysis takes two steps; documentation and defining obsolescence indicators for both

urban and building scales. The scarcity of street furniture, lack of accessibility of the streets and

buildings and the decline in business activities represent the most serious physical obsolescence

indicators, while, number of uneducated, unemployed, and/or high percentage of old aged occupants

represent the socio-economic indicators, like that in Valle and San Pablo or even cases of high

percentage of immigration like that of La Chana.


‘Interpretation’ for strategic action plans. Recommendations focus on 9 aspects underlining the main

management approaches that include; political, financial, structural, instrumental, digital, shared,

social, and community management, which aim at enhancing the neighbourhoods with better social

actions improving the training of the inhabitance in collective social work in order to stimulate social

cohesion and responsibility. This shall lead to improvement of the housing quality and the image of

the neighbourhood within the city which would enhance the real estate market.

Sustainable Energy performance indicators

Energy Analysis takes two steps; documentation and defining obsolescence indicators for energy use

on both urban and building scales. Documentation requires gathering general data on the urban scale

for; climatic zones and weather files, annual average temperature and humidity range, prevailing wind

direction and speed, as well as solar radiation range. While for the building scale, the type of data

should cover the monthly energy consumption, type of fuel used for energy production, type of

artificial lighting and HVAC mechanical systems used, occupants’ operational schedule, as well as the

type of building insulation. Discussing energy obsolescence indicators on the urban scale indicates

increased energy consumption due to the increasing demands of occupants’ comfort. While for the

building scale, shows a significant deficiency in the building energy performance of the thermal

envelope and building facilities, as a result of the high thermal transmittance of building envelope.


‘Interpretation’ for strategic action plans. Sustainability indicators can be retrieved by using green

rating systems. The addressed recommendations for sustainable rehabilitation plan aim at obtaining

comfortable, efficient, healthy, and protected indoor environment. This is by improving the thermal

and acoustic insulations of the building envelope, including the facades, external windows, and roof.

Finally, interpretations provide detailed building plans and sections for improving building envelope

as shown in Figure (8).



Figure 8 MBP Interpretations for improving building energy performance for Poligono del Valle-01,

IORN-MBP project

Matrix representation

The research further develops the following decision making matrix using weighted indicators for

obsolescence and sustainable rehabilitation as shown in Table (4). The value of (Y) should be equal to

or exceed the value of (X) to achieve a successful sustainable rehabilitation plan.

Table 4 Proposed MBP matrix representation

A: is the total sum of scores for physical obsolescence indicators

B: is the total sum of scores for socioeconomic obsolescence indicators



X=A+B: is the total sum of scores for obsolescence indicators

C: is the total sum of scores for physical sustainability indicators

D: is the total sum of scores for socioeconomic sustainability indicators

Y= C+D: is the total sum of scores for sustainability indicators

The value of (Y) should be equal to or exceed the value of (X)

DISCUSSION & CONCLUSIONS

The research develops a matrix structural analysis and decision making tool to present various sets of

alternatives for sustainable rehabilitation of social housing projects. The main aim of the matrix is to

build up a critical comparative perception of the problem and research phases, presented through a

process of selection, abstraction, prioritisation and interpretation of data processing. The matrix is

structured to adjust the relation regarding different scales and scopes of action. It acts as a simplified

interpretive tool that is capable of structuring the huge range of data obtained.

The research applies the research method on a case study project entitled: Interventions in Obsolete

Residential Neighbourhoods: Manual of Best Practices (MBP) (Promoted by Junta Andalusia,

University of Seville, Spain). The project studied eight neighbourhood plans with potential cultural

values but suffering incompatibility with contemporary users’ demands. The proposed method

presents a comprehensive toolkit that acts as an analytical and decision making tool for sustainable

rehabilitated plans using weighting and scoring of defined indicators. This shall set a datum for

sustainable social housing rehabilitation plans that would be considered as minimum requirements

asked from professionals where they are free to extend their creativity in design beyond these guiding

scores.

The structure of the matrix is flexible to respond to different contexts according to the selected

obsolescence and sustainability indicators, and also to add more scales and scopes of action depending

on the required research. It is also more readable; pointing out levels of strategic plans and timeline of

action, and achieves better communication with different decision makers to enable evaluation and

comparability for sustainable rehabilitation strategies.

BIBLIOGRAPHY

1. Chau, K. W. & Wong, S. K., Externalities of Urban Renewal: A Real Option Perspective, J Real Estate Finan Econ , 2014, 48:546–560, DOI 10.1007/s11146-013-9418-z, Published online: 28 March 2013, # Springer Science+Business Media New York, 2013 2. Field Recordings: Dundas Square, Toronto, Martin Hogue, Filed under Film Landscape, http://martinhogue.net/Field-Recordings-Dundas-Square-Toronto, retrieved October 2016. 3. GÜNEY, Yasemin Đ., Type and typology in architectural discourse, Balıkesir, 2007. 4. Incremental Housing and the (potential) Aestheticization of Poverty, Informalidad, H20 DF, A Blog. http://incrementalhouse.blogspot.com.eg/2008_02_01_archive.html, retrieved October 2016 5. Jeanneret-Gris, Charles-Édouard (lecorbusier), The Modulor, a harmonious measure to the human scale universally applicable to architecture and mechanics, first published in 1954, reprinted 2000. 6. Klein, Alexander, Relationships Between Architecture and Mathematics, the Existenzminimum: A ‘Scientific’ Approach to Design Techniques, Nexus 2010:, Porto, 13-15 June 2010. 7. Klopper, Rembrandt, Lubbe, Sam, and Rugbeer, Hemduth, The Matrix Method Of Literature Review , Alternation 14.1 (2007). 8. Krier, Rob, Urban Space, Academy Edition, Great Britain, 1979. 9. Mcewan, Carmen, Architecture of Analogy, the fragments as a category of Critique, 2013, available online https://cameronmcewan.wordpress.com, retrieved October, 2015. 10. Mcguirk, Justin, PREVI: The Metabolist utopia, Domus, Architecture, April 2001. 11. Moneo, Rafael, Theory on building Typology, Opposition, MIT, 1978 12. Munneke , Henry J. & Womack, Kiplan S., Neighborhood renewal: The decision to renovate or tear down, Regional Science and Urban Economics 54 (2015) 99–115, Elsevier, 2015 13. Rossi, Aldo,The Architecture of the city, MIT press, cambridge, Massachusetts, and London, England, 1984. 14. Shen, Liyin, Zhou, Jingyang, Skitmore, Martin, & Xia, Bo, Application of a hybrid Entropy–McKinsey Matrix method in evaluating sustainable urbanization: A China case study, Cities 42 (2015) 186–194, Elsevier, 2014 15. Tschumi, Bernard, THE LANDSCAPE Published by the Landscape Architecture and Urbanism programmes at the University of Greenwich, London, Manhattan Transcripts, 2014.

http://martinhogue.net/filter/Film

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http://martinhogue.net/Field-Recordings-Dundas-Square-Toronto

http://incrementalhouse.blogspot.com.eg/2008_02_01_archive.html

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16. Wiles, Rose, Crow, Graham, and Pain, Helen, Innovation in Qualitative Research Methods: Possibilities and Challenges, Cardiff School of Social Sciences, Paper: 121, 2008.

REFERENCES

1 Durand, J.N.L., Recueil et parallele des edifices de tout genre, Anciens et Modernes, Freal & C Editeurs,1801.

2 Bevilacqua, Marco G., 2010, and Klein, Alexander, the Existenzminimum: A ‘Scientific’ Approach to Design

Techniques. Nexus network,2011 3 Mcguirk, Justin, PREVI: The Metabolist utopia, Domus, Architecture, April 2001

4 Garcia-Huidoboro, Fernando, Torriti, D.Torres, Tugas, Nicolas, Time builds, EquipoArquitectura (EqA),2008.

5 Baek, Cheong-Hoon and Park, Sang-Hoon, Changes in renovation policies in the era of sustainability, Energy

and Buildings 47 (2012) 485–496, Elsevier, 2011 6 Iselin, D.G. and Lemer, A.C., The fourth dimension in building: strategies for minimizing obsolescence, in B.R.

Board (ed.): Studies in Management of Building Technology, National Academy Press, Washington, DC., 1993 7 Nutt, B., Walker, B., Holliday, S. and Sears, D. Obsolescence in Housing, Saxon House, Farnborough, 1976

1976 found in Thomson and Flier, 2011 8 (Itard et al., 2006; Power, 2010; Thomsen and van der Flier, 2009b)

9 Ibid, Iselin, D.G. and Lemer, A.C., 1993

10 Thomsen, Andre and Van der Flier, Kees, Understanding obsolescence: a conceptual model for buildings,

Building Research and Information, (2011) ,ISSN 0961-3218 print ⁄ISSN 1466-4321 online # 2011 Taylor & Francis http: ⁄ ⁄www.informaworld.com ⁄journals, DOI: 10.1080/09613218.2011.576328 11

GOETZ, EDWARD G., Obsolescence and the Transformation of Public Housing Communities in the US,

International Journal of Housing Policy, 2012, Vol. 12, No. 3, 331–345, ISSN 1461-6718 Print/1473-3269

Online 12/030331–15 C _ 2012 Taylor & Francis, http://dx.doi.org/10.1080/14616718.2012.709671 12

Vehbi, Beser O., & Hoskara NAL HOS, EBNEM O¨, A Model for Measuring the Sustainability Level of Historic Urban Quarters, European Planning Studies Vol. 17, 2009, ISSN 0965-4313 Print=ISSN 1469-5944 Online=09=050715–25 # 2009 Taylor & Francis, DOI: 10.1080/09654310902778201 13

Chau, K. W. & Wong, S. K., Externalities of Urban Renewal: A Real Option Perspective, Real Estate Finan Econ (2014) 48:546–560, DOI 10.1007/s11146-013-9418-z, Springer Science+Business, also citing (Brand, 1994; Maver, 1979; Till, 2009; van Nunen, 2010) 14

Ibid, Vehbi &Hoskara (2009) 15

Ibid, Thomsen and van der Flier, (2011) 16

Ibid, Vehbi &Hoskara (2009) 17

Ibid, Vehbi &Hoskara (2009)

http://dx.doi.org/10.1080/14616718.2012.709671

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PERCEIVING SOCIAL HOUSING THROUGH MATRIX STRUCTURAL ...architecturemps.com/wp-content/uploads/2016/04/SALAHELDIN-D-et-al... · PERCEIVING SOCIAL HOUSING THROUGH MATRIX ... Matrix