INTEGRATED PLANNING SUPPORT SYSTEM FOR LOW-INCOME HOUSING Funded by DAAD and CONICYT by means of the Alechile program (File Nr.: 415-alechile/ale-02/21700)

Final Report 28.02.2005 Donath, Dirk and González, Luis Felipe Chair Computer Science in Architecture, Faculty of Architecture, Bauhaus-Universität Weimar, Germany caad@archit.uni-weimar.de

Abstract

This article reports the research work carried out in the last period of funding time between 01.02.04 and 28.02.05, and final outcomes. The research project focused on the analysis and design of a concept of computer-based information system to support planning processes of low-income dwellings. The testbed was the participative-planning strategy of progressive development dwellings in Chile. This low-income housing model highlights two particular features, first the predominant involvement of dwellers into the decision-making along the planning process, and second, the class of progressive development dwellings. The main goal is to improve design and planning methods for this class of dwellings.

Problem domain

The implementation of progressive development housing strategies has proved over the last years, to be a reasonable alternative of reducing the quantitative and qualitative deficit of housing in Chile. The component-based approach applied on the low-income housing production aims at an optimisation of resources, and the dwellers active participation into the planning process, sometimes including self-construction activities, provides user customized dwellings. The progressive growth of the dwelling and its modification over time, in order to satisfy further habitability needs of its inhabitants, became better adapted tools to the economic reality of a large segment of low-income population. Besides, the participative-planning model, implemented in a smaller scale, through collaborative work between NGO’s and middle size groups of dwellers, eases the planning and the execution of housing projects. The diversity of progressive development housing strategies carried out within the last 50 years in Chile is shown in Table 01.

Table 01. 50 years of progressive development housing strategies in Chile

Land

ten

ure

(pro

visi

on o

r re

gula

riza

tion

)

Urb

an in

sert

ion

Hyg

iene

Shel

ter

Ope

rati

ng p

erio

d in

Chi

le

Types of progressive development housing strategies

Site

Infr

astr

uctu

re1

Latr

ine2

Sani

tary

-Uni

t3

Stru

ctur

al

elem

ent

alon

e4

Mul

tius

e-ro

om

3 ro

oms

‘Site-and-services’ (variant A) • • ‘Site-and-services’ (variant B) • • • ‘Site-and-services’ (variant C) • • •

‘50s - ‘70s

‘Site-and-services’ (variant D) • • (•) • ‘Operation chalk’ • •

‘60s ‘Operation site’ • • • (•)

‘80s - now ‘Neighbourhood upgrade’ (•) • (•) (•) ‘Progressive housing’ (variant A) • • • ‘90s - now ‘Progressive housing’ (variant B) • • • •

2002 - now ‘Dynamic debt-free social housing’ • • • • • 1. Infrastructure: construction, installation or reparation of roads, water supply, drainage, electricity or a sanitary

network 2. Latrine: basic bathroom and/or toilet 3. Sanitary-Unit: bathroom, toilet, and/or a space for a kitchen 4. Structural element: either only a utility wall (structural wall with infrastructure connections); a roof structure on

posts; a plinth; or a roof and two side walls, but without front or rear walls (•) and/or

Table 01 indicates two components to be the most important in all types of this class of strategy: a plot of land, and its insertion into the urban system. The tenure of a plot of land attends socio-cultural features, and the urban insertion by means of endowing infrastructure does not only attend hygienic deficiencies of the communities. The effect of including people’s living environment into the urban network also supports the empowerment of community, by leaving marginality. Table 01 also shows a clear tendency over the time to increase the number of spaces within the initial endowments. Today, the class of progressive development housing strategies achieves a large part of public investment into social housing production, and an increasing action-field by means of several supporting housing programs. Over the last two years, the Chilean government has been re-evaluating and redesigning the habitability minimum standards for social housings. These standards have been incorporated into the planning specifications for the new type of progressive development dwellings, called ‘Dynamic debt-free social housing’. The new standards intend to come closer to international ones, like the DIN 18022. Graphic 01 shows the great increment of dynamic debt-free social housing production in Chile, compared to conventional low-income housing within a lapsed period of 3 years and prospecting.

Graphic 01. Low-income housing production in Chile 2000-2006

010.00020.00030.00040.00050.00060.00070.000

2000 2001 2002 2006

years

Source: Ministerio de Vivienda y Urbanismo de Chile, 2003

unit

s

dynamic debt-freesocial housing

conventional socialhousing

Total

The participative-planning models initiated back in the ‘50s, have been improved over the years, particularly after the incorporation in 2001 of publically awarded funds procedures for housing projects. This model supports collaborative work between NGO’s and middle size groups of dwellers by participative-planning and building of small or middle size groups of users-customized dwellings. Furthermore, each housing project has to be accompanied by social plans aimed to the empowerment of the community. Table 02 shows the actors and their participation within the current participative model of low-income housing production in Chile.

Table 02. Current participative model of low-income housing production in Chile

Agent Demand Resources Offer

Low-income dweller

Housing ownership

Access to supply systems

Access to income-generating activities

Participation into decision-making

Technical support

Savings account

Strong social networks

Manpower

Empirical knowledge

Adaptability

Self-construction

Household management

Decision-making competence

Cooperativeness

Planner

Contracts

Transparent public bidding procedures

Acceleration of building permit procedures

Simplification of planning and zoning regulations

Planning and design methods and tools

Problem-solving procedures

Entrepreneurial structure

Design alternatives

Suggestions for better habitability standards

Technical support

Building contractor

Building contract

Investors

Assurance of project execution

Domain-specific knowledge

Production machinery

Building technology

Dwelling spaces and infrastructure

Building quality assurance

Technical support

Jobs

State

Housing deficit reduction

Public resources optimisation

Participation of private sector into development, execution and financing of projects for marginal sectors

Fair distribution of supplies

Tax receipts

Administrative provision of public budget

Regional planning instruments

Largest administration machinery

Largest data acquisition performance

Largest data bases

Housing programs

Debt-free subsidies

Publically awarded funds

Tax concessions

Contract awards

Supervision machinery

Research assignments

Financing institution and real estate company

Indemnity against indebtedness

Investment projects

Long-term accounts

Receipt of interest

Investment capital

Administrative provision of private capitals

Building loan contracts

Credits on mortgage

Together with the active participation of dwellers into the planning and building processes, a very important issue concerns the provision of technical support. Until now, and for the rest of the current participative-planning models outside the procedures of publically awarded funds for housing projects, the provision of technical support has been very expensive and sometimes very inefficient. Regarding current procedures of personalized attention at official agencies, and aid-tools like planning and building printed manuals, the possibilities of providing efficient technical support for large groups of dwellers simultaneously, are actually very scarce. Especially in the field of progressive development housing, current aid-procedures are unable to trace the life-cycle of dwellings in order to provide technical support at any stage of enlargement or modification over time.

Thus, the reality shows that after the first technical supported stages of the progressive growth, planers and official agents lose the track on the further development of the dwellings, so that long-term technical support becomes in most of the cases impossible to be carried out. Table 03 shows the standards of human resources invested for technical support procedures, established in 1997 and valid till now. Table 03. Human resources in technical support for self construction housing in Chile

Number of experts and their qualification

Project manager Experts team (pers./area) Amount of households to assist Professional from

construction, social or legal areas

Construction area

Social area

Legal area

People amount

from 1 to 400 1 1 1 1 4 pers.

401 – 800 1 2 1 1 5 pers.

801 – 1200 1 3 1 1 6 pers.

1201 – 1600 1 3 2 1 7 pers.

1601 – 2000 1 4 2 1 8 pers.

Source: Ministerio de Vivienda y Urbanismo, División Jurídica, Resolución Nr. 533, (V. y U.), de 1997, JTF/AHM/CMR, 31.07.2004.

The field-exploration carried out in November 2003, on a ‘site-and-services’ settlement, founded in 1974, in San Pedro de la Paz, Concepción, Chile, shows a persistent evolution of progressive development dwellings over large periods of time. The superimposition of 15 cases of dwelling enlargement or modification activities, carried out in 29 years, revealed the existence of a cyclic development of the dwellings. Graphic 02 clearly shows three development cycles within the mentioned period of time. The development cycles become more distanced over time, and their magnitude decreases also over time. The studied settlement, presented various cases of shape and of colour modification of the dwelling, again at the end of 2004.

Graphic 02. Development cycle 1974-2004

0

10

20

30

40

50

60

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31

Chronology (years)

Bui

lt s

urfa

ce a

vera

ge (

m2)

The reason why Graphic 02 shows 32 years instead of 29 is because the chronology axis on this graphic counts the initial endowment of 6 m2 built surface as year 1, although the first enlargement activities showed up, in all cases, within the firs year. So year 2 on the chronology axis corresponds actually also to year 1. Besides, the year of 2004 is also represented as the 32nd year, but without any enlargement activities (by the time the field-exploration was carried out). Some of the initial research objectives of the field-exploration, was to detect possible vernacular rules of geometric or topologic nature, within the dwellings development. Such rules should have made us capable of to predict user behaviours and to preset building typologies. It came out that; indeed there are some similarities between the studied cases, but nothing we could define as a particular class of distinctive rules. Due to the knowledge gained through further analysis, we realized that these particular expectations contradict the objectives of the participative-planning support system we had in mind.

Five useful statements were deduced from the field-exploration: (1) solar orientation does not greatly influence the allocation of different function-related spaces, but the position of the initial endowment (in this case, the sanitary unit) does. One clear exception is case 06, where after the first growth stage, carried out around the sanitary unit at the north-east side of the lot, they demolished the house, to rebuild it along the south-west side of the lot. Keeping the same architectural program, they linearly built the new house, in order to gain more insolation surface. (2) The adjacent allocation between the initial spaces (in this case, a bath and a kitchen) and their allocation into the lot, strongly determine the posterior need or needlessness of corridors, in order to allow circulation systems. The same factor determines, by forthcoming house enlargements, the need of inner courtyards, in order to obtain natural light and ventilation for every space. So the efficient design of topologic relations between spaces reveals to be a very important issue within the planning process. (3) Spaces capacity, i.e. the flexibility of a space to change its function without having to change its size, was validated only in 4 cases. Nevertheless, a plausible reason for that could be the very unusual large size of the lots that allow very expansive cellular growth. (4) More than half of the cases (8 cases) built 2 bedrooms at the first stadium of enlargement. There were three cases with 3 bedrooms, three cases with 4 bedrooms, and one with 1 bedroom. This fact becomes relevant, when comparing it with the minimum standard program defined into the Art. 6.4.1. of the ‘Special regulation for economic housing’ 1, namely, three built spaces, one with capacity for at least two beds, one with capacity for a WC, shower and lavatory, and one space with capacity for kitchen and dinner-living room. (5) In all cases, the living room is allocated at the front side of the house, together with little shops or workshops. All bedrooms are distributed towards the background of the lot. Table 04 shows the 15 cases registered in November 2003, in San Pedro de la Paz, Concepción, Chile. The current housing subsidy system operating in Chile is even better than the national census system itself. Application procedures, registration, and assignation of subsidies operate online, by means of network-based information systems. Nevertheless, the planning and building processes of low-income dwellings lack of any IT-support. The main deficiencies into the participative-planning models for progressive development dwellings, concern the lack of cost-efficient technical user support, clear and user-friendly decision support systems, user facilities management tools, collaborative work tools oriented to architectural design tasks, and planning-relevant information systems.

1 Ministerio de Vivienda y Urbanismo: Ordenanza General de Urbanismo y Construcciones, Título 6. Reglamento Especial de Viviendas Económicas, Capítulo 4. De la Arquitectura, Artículo 6.4.1., § segundo, April 2004, pág. 315.

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case 01 case 03 case 05 case 07 case 09 case 11 case 13 case 15Middle site Middle site Corner site Corner site Middle site Middle site Middle site Middle site Middle siteMiddle site Corner site Middle site

1974

1974

1998

1974 1974 1974 1974 1974 1974 1974 1974 1974 1974 1974 1974 1974 1974

1998

1985

197419741974

1999

1974

1980

2000

1974

1985

1974

1982

1995

197419741974

1984

1997

2000

1974

1980

1999

1974

1979

1994

2003

1974

1985

1995

1974

1995

2001

1974

1980

1986

Middle site Middle site Middle siteW: 10.50m D: 20m W: 12m D: 17m W: 10.50m D: 21.50m W: 10.50m D: 21.50m W: 10.50m D: 20m W: 10.50m D: 25m W: 11.50m D: 20.75m W: 10m D: 27.50m W: 11.50m D: 20m W: 12m D: 17m W: 12.20m D: 17mW: 12m D: 17mW: 12m D: 17mW: 12m D: 17mW: 12m D: 17m

Location of the studied cases

S

K

B

A

Bedroom

Kitchen

Bathroom

Corridor and/or stairs

Storeroom

Inner courtyard

E/W Dining-/ living room W/L Workshop and/or shop

F

Architectural program

Table 04: Comparison of the evolution among progressive development dwellings / Field-exploration / Settlement San Pedro de la Paz / Concepción / Chile / Nov. 2003

T

Stadium

1Initial end

owm

entStad

ium 2

Stadium

3Stad

ium 4

case14case 12case 10case 08case 06case 04case 02

Hypothesis and Demonstrations

01. Modular system architectures support the integrative combination of heterogeneous IT-tools, optimise

processing energy, and ease system maintenance.

We proposed a logical structure, consisting of three modules to support, the acquisition of planning-relevant data, the user customized design, and consulting procedures. Each module is defined by its functionalities, in order to solve specific tasks of the design problem. Besides, an open architecture, based on a collection of modules, provides a high degree of flexibility to integrate individual tools (function components) within a common logical structure. Future development of the system aims to support logistics involved into purchase and delivery services of construction materials. Modularity will ease the upgrade of the system, by means of the integration of new independent support tools (program applications). Diagram 01 shows the model proposed for the system architecture.

Numerous current research publications, related to multi-user design environments, e.g. [Cumming ‘04], [Orzechowski ‘04], [García ‘02], [Galli ‘00], [Ozkaya ‘00], and to modularity into software development, e.g. [De Souza ‘04], [Prasad ‘04], [Sullivan ‘01], and [InfAR ‘01], promote and demonstrate the advantages of the criterion of using modular system architectures.

02. Network-based platforms enable many users (e.g. planners and dwellers) to access the same data content

simultaneously, aside from the technical aspects of flexibility and wide range of physical spreadability.

In fact, Wide Area Networks are able to provide data communications to a large number of independent users. Furthermore, using standardized air interface protocols (wireless access mode) enables to spread its action-field over a large geographic area, in order to provide access to remote located users. This is a very important feature, considering Chile’s demographic density of 20 Inhab./km2. The mass implementation of the network-based approach into highly integrated, distributed systems, validate its advantages in regard to CAAD collaborative platforms. Related literature confirm the spread use of this approach, e.g. [Thurow ‘04], [Seichter ‘03], [Seichter ‘03*], [Petzold ‘01]. Simply, by using the Internet as medium for transporting data, and communication securing tools like VPN technologies (virtual private network) or similar, enables our planning support system to utilize public wires to spread out, but ensuring that only authorized users can access the network and that the data cannot be intercepted i.e. data integrity. Scheme 01 shows a model of VPN supported network. 2

2 Cisco Systems MR.: Figure “Sample IPSec-to-MPLS Deployment Architecture”, found in the internet, 2005 in url: http://www.cisco.com/en/US/netsol/ns341/ns396/ns172/ns143/networking_solutions_white_paper09186a008009d67f.shtml

Currently, the advantages of using VPN technologies-like have been validated in many fields of ICT [Raghunath ‘04], [Adtran ‘01]. "Face-to- face meeting time between architect and client is always limited, while a computational system is infinitely patient." [Larson ‘01] A network-based implementation to provide technical support any time, anywhere, during the growth cycles of progressive development dwellings is plausible, especially when table 03 shows the current alternative.

03. The set of topologic valid solutions for spaces-allocation alternatives, defined by a specific design problem,

contains a quantifiable number of elements.

Given the design problem 01 (DP-01). DP-01 defines the minimum architectural program for social housing (in Art. 6.4.1. of the ‘Special regulation for economic housing’ 3). Three built spaces, one with capacity for at least two beds, one with capacity for a toilette, shower and lavatory, and a third built space with capacity for at least a cooking place, dinner and living room. DP-01 describes 3 built spaces and the third of them is subdivided into 3 function areas, and they stay together. Additionally, DP-01 includes the solar orientation, i.e. the four cardinal points (N, E, S and W). The goal of a first part of the exploration was to find the set of topologic valid solutions for DP-00, namely, just three spaces, not considering the intern subdivision of the third space, mentioned above. The empirical exploration gave a set of 36 valid solutions. Their graphic representation is based on Fleming’s compact, two-dimensional “T-Floorplan” representations [Fleming ‘77]. There actually exist only two ways of allocating three spaces adjacent to one another, linear or network-based. The following adjacency graphs show the two ways.

3 Ministerio de Vivienda y Urbanismo: Ordenanza General de Urbanismo y Construcciones, Título 6. Reglamento Especial de Viviendas Económicas, Capítulo 4. De la Arquitectura, Artículo 6.4.1., § segundo, April 2004, pág. 315.

Three students of the course “Selbstgestrickt: CA(A)D-Systeme anpassen und erweitern” carried out by our chair “Informatik in der Architektur” were in charge of elaborating a routine in AutoLisp (RM), to draw two-dimensional 3-spaces-allocation configurations, based on parametric input. This function-component is able to be integrated into any release of Autocad (RM) up the 2000 R. We proved the first part of the exploration, by the automated drawing of the set of 36 valid solutions for DP-00, supported by this routine. Hence, the problem of nested permutations for DP-01 considers a total of 8 elements, packaged in 4 groups. The first two spaces described above, built one group of elements (2!), the other group that also contains two elements, is shaped by the cardinal points that orient the whole 3-spaces configuration, and the cardinal points that orient the 3-function-areas configuration (2!), the 3 built spaces shape a group of 3 elements (3!), and finally, there is the group of elements containing one element (1!), shaped by the 3-function-areas configuration.

In order to verify hypothesis 03, we explored all possible undirected graphs to describe the set of topologic valid solutions for DP-01. Again, based on Fleming’s compact, two-dimensional “T-Floorplan” representations and procedures towards automated space allocation [Fleming ‘77]. 36 different adjacency graphs came out. The representation based on graphs, supports the modelling of the computer intern representation of spaces-allocation configurations. Table 05 shows all possible adjacency graphs that match the entire set of topologic valid solutions for spaces-allocation alternatives to solve the design problem 01. The arcs with continuous line represent the adjacency relations between spaces and between function areas. These relations keep constant. The dashed arcs represent topologic relations that vary, corresponding with possible rotations of the graph. Thus, we were not forced to draw every possible rotation of the graphs. The nodes are unlabeled, what gives us the freedom of not having to draw a new graph to represent each set of permutations, between elements. In order to draw the 1.680 topologic valid solutions, based on Fleming’s compact, two-dimensional “T-Floorplan” representations, we explored the research field of “two-dimensional cutting stock problems” and paradigmatic algorithms [Wang ‘83]. Parallelly, we carried out short tests on an old, but very clear program application called Woodworks (RM). Picture 01 shows a few examples of these tests.

Wang’s algorithm basically describes a recursive search procedure, similar to empirical exploration. Due to the effort and time consuming, required to readapt Wang’s algorithm to our very specific problem, in order to set up a prototypical implementation, we decided to draw the topologic configurations by means of standard CAD tools of Autocad 2000 (RM).

G4.

W W W W

W

W

G4.2 G4.5 G4.6

G4.17

G4.19

G4.3

W W

G4.4

G4.11

W

W

G4.13

G4.27

W

W

G4.21

W

G4.31

W

G4.7 G4.9

W

G4.33

W

G4.16

W W

G4.15

W

G4.8 G4.10

W W

G4.12

G4.14

W W

G4.18

W

G4.20 G4.22

W

G4.24

W

G4.23

W

W

G4.25

W

G4.26

W

G4.28

W

G4.29

W

G4.30

W

G4.32

W

G4.34 G4.35

W W

G4.36

Table 05. These 36 undirected graphs describe every possible allocation of spaces and function areas for design problem 01

© Luis Felipe González Böhme, 2005

04. The constraints-based design approach becomes an efficient tool to support users’ decision-making during

the planning processes.

A design problem can be entirely described, by means of its specific design constraints [Gross ‘85]. Field-explorations and literature research proved that, when non-designers face the design problem, the only reliable data they manage and the only decisions made until that moment, are solely related to a certain set of constraints (budget, regulations, time cost, etc). In order to support data modelling, these constraints can be organized into a useful taxonomy. We defined two classes of constraints, based on their expression: topologic and geometric. Next, we defined two subclasses of topologic constraints. The first subclass is defined by regulations. We defined three types of constraints that belong to this subclass. The second subclass is defined by design criteria. Two types were preliminary described, and proved in a three-phases experiment, showed next.

05. The accumulative application of design constraints gradually reduces the number of elements contained

into the set of valid solutions for a specific design problem. This procedure supports a consequent decision-

making process.

In the first phase of the experiment, we proved this procedure, on the 1.680 topologic valid solutions for DP-01. The result of applying five topologic constraints during the solution-finding procedure, gave 303 valid solutions for DP-01. This is a significant decrease down to 18%. Graphic 03 shows the significant decrease curve of the set of valid solutions, by a sequential, accumulative application of constraints.

Graphic 03. Sequentia l , a ccumula tive applica tion of constra ints

0200

400600800

100012001400

16001800

1 2 3 4 5 6

constraints (quantity)the first datum represents the entire set of

solutions (1680)

topo

logi

c va

lid s

olut

ions

Topologic valid solutions(accumulative results)

An interesting fact of the experiment is that we worked with very few conventional topologic constraints. User-defined topologic constraints were absolutely excluded. It means, that when it comes to add individual user’s set of topologic constraints, the set of valid solutions will reduce significantly, to a more manageable number of solutions. The same conclusion is valid for the set of geometric constraints to come. The second phase of the experiment was to define two instances of the class of two-dimensional spaces-allocation configurations: (1) the duplex house typology, and (2) the row house typology. It came out, 235 topologic valid solutions for the duplex house typology, and 202 topologic valid solutions for the row house typology.

06. The application of planning and zoning regulations, valid for a specific design problem, is described as a

complex system of non-redundant combinations of those regulations. A computer-based system is enabled to

build every required combinations, and to use them as search parameters for constraints-adapted solutions.

The third phase of the experiment was to apply a set of geometric constrains, defined in the planning specifications for a real ‘Dynamic debt-free social housing’ project, at the north riverside of Concepción, Chile. This task was carried out as part of the design workshop “Bauen für die Armen – sozialer Wohnungsbau in Chile”, conducted by Prof. Dr.-Ing. Dirk Donath and PhD candidate Luis Felipe González, during the winter semester 2004-2005. The list of legal constraints resulted, indeed from the combination of the General Ordinance of Urbanism and Building, the Local Ordinance, and technical specifications of the ‘Dynamic debt-free social housing’ program. Thirteen legal geometric constraints were modelled and tested on six classes of three-dimensional spaces-allocation configurations. The main obstacle for the students, during the constraints-based design process, was to define an application model for the thirteen legal constraints, in order to test several spaces-allocation configurations. The exercise proved the first sentence of hypothesis 06. After the students gained expertise on this task, they were asked to describe a valid sequence to apply those legal constraints. The sequential description for an application method of geometric constraints, defined by the planning and zoning regulations, will be analysed in order to built a relevant algorithm. Picture 02 shows fifteen alternatives of progressive development dwellings.

Legal geometric constraints, in addition to cost-saving criteria, opened further exploration on three-dimensional spaces-allocation alternatives, and new possible set of solutions. Nevertheless, the legal geometric constraints, in addition to the extremely little size of the lots, used in the real context of social housing, gave a very reduced set of fifteen possible dwellings alternatives. Picture 02.1 shows the possible topologic relations for three-dimensional spaces-allocation configurations.

07. It is possible to get diversity, starting from a finite repertoire of design alternatives.

The component-based design approach is well known in product manufacturing, and prefabricated building industry. Component-based architectural design supports mass-customisation procedures in the housing production. In order to prove hypothesis 07, based on some aspects of the SAR design method [Habraken ‘81], we preset a repertoire of function-related spatial units, and tested them on the design process of the workshop. The design problem for a function-related spatial unit belongs, together with the two-dimensional spaces-allocation problem, to a same class. Only this type of problem concerns the allocation of furniture and artefacts within a determined area. We used both, the DIN18022 and Chilean “Habitability Standards” to decompose the area of a function-related spatial unit, and optimise the allocation of furniture within it. The students were asked to work only with these spatial units, but with the freedom of modifying them, as long as the 30cm-module and the standards remain intact. Only in very few cases, the internal circulation zones of bedrooms were reduced, in order to reduce the size of the spatial unit. Picture 03 shows some examples of the repertoire tested in the workshop.

08. The use of objects libraries embedded in existent CAD systems, reduces the implementation of little

function components (modules), to a simplified data structure modelling, with simple arithmetic and logical

operations.

In order to test, to prove this hypothesis, and to introduce user’s geometric constraints into the design problem, we used the Expression-tool (MR) of the software Cinema 4D v. 8.5 to model the possible data structure for a little experimental application. The application allows first, to input the area value of a given rectangular surface S, and to modify its contour proportions, keeping the area value constant. Surface S, represents the ground floor geometry of a dwelling. Second, the modifications on surface S, affect the shape of a given 3-spaces compact configuration C. The three spaces represent the minimum architectural program for social housing, described in DP-01. The spaces are adjacent to one another, and only separated by a fugue of 10cm. The width of this fugue is a constant value, which is also modifiable on the Cinema’s GUI. The fugue represents a partition wall. Notice, that the three spaces, including the fugues, sum the same area of surface S modified before, and that the whole configuration C, automatically adopts the same contour shape of surface S. Third, the user is allowed to input independent values to modify width or length of each space, what of course, will automatically modify the shape of the other space, in order to keep the geometry of surface S. The GUI of Cinema (MR) allows carrying out every modification mentioned before, either by means of text-based or drag ‘n drop procedures, directly applied on the 3D model. Such a basic, but useful application for preliminary design tasks is missing among the market leaders CAAD systems. The reuse of pieces of software, and the integrative combination of application modules into existent platforms, are plausible procedures towards an optimisation of the resources. Picture 04 shows some screenshots of the application on Cinema 4D (RM). Picture 05 shows the data structure of the application.

Educational Aspects

The main goal of the workshop carried out during the winter semester 04/05, was to train the students in structured thinking, in order to be able to develop and to follow consequent design and evaluation procedures. Another goal was to introduce design methods. The exercise in minimized design provided them new points of view on the field of architectural design. Teaching about the requirements of participative-planning strategies and the confrontation with different social realities, opened the minds of the students and enabled them with new skills for architectural practice. The exploration process carried out, and the design outcomes of the workshop, are online. This was requisite, in order to achieve a prototypical implementation of a web-based platform for a planning information system, to support participative-planning processes of progressive development dwellings (in this case, Dynamic debt-free social housings). The platform provides a catalogue of dwelling alternatives, supported by planning-relevant data, like printable planning documentation, cost-estimation, and 3D models visualization (e.g. walk-through). We introduced the students the concept of Building Information Models, linking VRML-models directly with planning-relevant information. The web-based platform url: http://infar/infar/deu/lehre/archiv/semesterentwurf/freie_entwuerfe/ws04/ws04_chile/index.htm

Conclusions and further research

The duty of architects, within professional practice, is to make complex decisions during the planning process, often based on unreliable information, and expecting permanent changes. This statement matches the participative-planning scenario too, and it sharpens in the field of progressive development housing planning and execution. In participative-planning, architectural practice, becomes a matter of technical support provision. Information Technology offers a wide range of methods and applications, in order to provide cost-saving support to participative-planning strategies. Expectations on digital technologies are running out. Too many promises, together with an unreasonable effort, shape the current reality. Apparent improvements by means of promised advantages like universality, efficiency, integration, and etc contrast with the actual dependency, technological unreliability, systems incompatibility, decreasing of expertise and of the demand-cover level. Every current computer-based system work exclusively discrete and endure mostly only an illogical, sequential use. Today, the work with separated application programs, on current conventional CAAD platforms, is cost-inefficient. The planning process can be decomposed into small consequent steps that are able to provide efficient support in the development of modular computer-based systems. The clear description and structuring of produced planning-relevant information would be enough, for a first step in this direction. Hence, another use and adaptation of systems and devices, is fundamental requisite, e.g. innovative I/O devices, on-site computing (wearable devices), Building Information Models, wireless networks, Tool-Kit approach for modular systems development, and transparent and consequent procedures. We expect in the forthcoming months, to test the web-based platform on field, in cooperation with the Universidad del Bío Bío and a NGO involved in the development project for the north riverside of Concepción (Ribera Norte) The field-test will adjust technical aspects of a forthcoming GUI and automation criteria in participative-planning support. For more information about ‘Esther’: http://infar.architektur.uni-weimar.de/alechile/index.html

References

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