A New Palladian Shape Grammarpapers.cumincad.org/data/works/att/ijac201210404.pdf · Ray Lattices [9] and the De Stjil paintings [10].According to Knight,there are three types of

521

A New Palladian ShapeGrammarA Subdivision Grammar as alternative tothe Palladian GrammarDeborah Benrós, José P. Duarteand Sean Hanna

issue 04, volume 10international journal of architectural computing

522

A New Palladian Shape GrammarA Subdivision Grammar as alternative to the Palladian GrammarDeborah Benrós, José P. Duarte and Sean Hanna

Abstract

The following paper describes a shape grammar that recreates Palladianvillas.A Palladian grammar was originally proposed by Stiny andMitchell. However, this alternative grammar uses different parametricshape rules and methodology to test the hypothesis that differentgrammars can generate the same corpus of designs.The formalism isthen implemented using a computerised design tool.The grammarincludes subdivision rules that allow for a more economicalformulation.A new corpus of solutions is explored and the derivation iscompared with the original Palladian grammar. The project is part ofwider research aimed at formulating a generic housing grammar.

Keywords: Shape grammar; Design Rules; Housing Grammar

1. INTRODUCTION

This research paper describes the methodology used to recreate Palladio’sdesign signature using a formalism called shape grammars. Stiny and Mitchell[1] illustrated the range of shape grammars and its first architecturalapplications.The present work revisits their work presented forty years ago,by proposing an alternative grammar incorporated into a computer tool.The novelty of this research lies in the demonstration that more than onegrammar can generate the same design solutions. In the majority of cases,shape grammar research has tended to produce only a single grammar for agiven corpus of work, but we feel it is the comparison of different grammarsfor similar or partially overlapping corpora that will yield greater insight intoquestions of style and representation. Moreover, this research is seen as aninitial step in the development of a generic grammar for housing, a conceptapplied in urban contexts by Beirão et al [2]. It is hoped that by breakingthe tacitly assumed equation of a single grammar with a single style,significant steps may be made toward this goal.

The notion of grammars and universal grammars has been widelydiscussed by the linguist Noam Chomsky [3]. He describes how differentlanguages containing different roots encapsulate basic phrase formulationand an innate sense of grammar.The idea of a universal grammar explainsthese innate formulations. Subsequently, the notion of grammar wasintroduced into the field of geometry and algebra providing a method bywhich complex shapes are described and generated [4, 5, 6].

A shape grammar is a structured formalism that incorporates a limitednumber of shape rules to describe geometric operations.These consist ofan initial and a final stage, with a transformation, or geometric operationoccurring between them. Combining different shape rules and orderingthem into a shape grammar enables design styles to be recreated, such asthe grammars for the Prairie houses [7], Siza’s Malagueira houses [8], Ice-Ray Lattices [9] and the De Stjil paintings [10].According to Knight, thereare three types of shape grammar processes: grid, addition and subdivision[11].

Grid grammars propose a form of design generation based on arectilinear arrangement of cells, and can either build up by aggregation, orrefined by subdivision. In the first case, the design is derived from the gridusing cell merging processes. In the latter, subdivision creates a designconfined by a boundary and the solution is achieved through a succession ofdivisions.The two Palladian grammars differ primarily in this point, as theoriginal Palladian Grammar used a grid process to address the symmetricalrectangular floor plan, while the proposed alternative grammar uses asubdivision process.The justification for the use of subdivision is threefold:firstly, it represents a potentially more intuitive way of designing in that itcorresponds to the way in which a designer generally works with an entireplan as a single entity, secondly, it allows for fewer shape rules and is more

523A New Palladian Shape GrammarA Subdivision Grammar as alternative to the Palladian Grammar

economical, easier to use, and thirdly it proposes a different process, thusproving that two distinct formulations can generate same results.

The rule extraction process was based on observation of differentexisting villas, examining each floor plan, number of rooms, proportions,geometries, spatial adjacencies and communicating rooms.The layout of thefloor plan for each villa uses 9 basic rules in contrast with the 25 used inthe original grammar and all the shape rules have a parametric formulation.The initial rules define the boundary setting, whilst the rules that followpropose subdivisions. Other rules allow for the merging of consecutive cellsby erasing borders.The design is completed by allocating centrally alignedopenings in accordance with Palladio original specifications [12]. Functionswere not addressed in the original grammar, but were incorporated in thisstudy. It was possible to identify the functions in unlabelled sixteenthcentury villas by observing spatial adjacencies, using comparison as amethod and taking proportion, shape and area into account. Notions ofshape syntax integration and segregation were also considered asdemonstrated by Hiller and Hanson [13].A computer tool was created anddeveloped in AutoLISP.The routine created provides non-shape grammarusers with a visual platform for exploring design.The script is easilyaccessible to non-proficient CAD users and allows for real time 2D designgeneration and 3D model visualisation.

Previous studies have proved that an extensive corpus of designs can beproduced from limited design rules as shown by Stiny and Mitchell [14].Theoriginal grammar allowed for the production of 220 different solutions forgrids of 5x3 cells.A generic grammar would allow for the design of morethan one type of signature style and an extended corpus of solutions.

The relevance of this study is related to the wider aim of proposing ageneric grammar for housing. Studies on grammars have been limited toillustrating specific styles, but no two different grammars with a distinct setof rules have been investigated with respect to the partial overlaps in thecorpus of designs they produce. There is more than one method forobtaining a grammar that incorporates style.This paper is organized into 7sections. Section 2 explores the grammar formulation, whilst Section 3describes the shape rules system and Sections 4 and 5 focus on the villaderivation and generation of new designs.The computer implementation isdiscussed in section 6.The final section contains the conclusion, future workand comments on the results.

2. FORMULATION AND METHODOLOGY

The grammar formulation and rule inference derived from the analysis oftypical Palladian villas.The study and observation of the existing villas builtby Palladio or illustrated in his treaty hinted a methodology that divergedfrom the original grammar.A subdivision process was selected leading to atop-down approach which seamed more suited due to its instinctive nature.

524 Deborah Benrós, José P. Duarte and Sean Hanna

This analysis resulted into the extraction of design principles that wereencoded into shape rules.The shape rules were sequentially ordered indifferent stages and a test performed to generate solutions through aderivation process.When proved operational the shape grammar wasscripted into a computer tool for faster and easier implementation.

2.1.Approach

A top-down approach was used.The design process begins with the overallshape and evolves to further detailing.The self-contained shape forboundary is set and a series of tasks are carried out to refine the design.The starting point for the proposed alternative grammar was theexploration previously inferred grammars. Using Knight’s grammarclassification as quoted by Prats [15] a case study was selected, comprisinggrid (Palladio), addition (Wright) and subdivision (Siza).The grammarstructures were compared and the results led to a proposal that addressedthe basics of housing design and was related to Palladio’s signature design.The existing villas were observed. Certain generic features describe thefamily of designs known as Palladian villas: a rectangular envelope constitutesthe boundary and the villas are composed of a raised ground floor whichhosts the main social areas.A lower ground floor contains the service areas,pantries, kitchens and servants quarters.The upper level contains living andbedroom areas for the house owner and family.The main floor is raised bysteps and has enlarged headroom, with an impact on the façade.This is theonly floor plan usually illustrated in Palladio’s writings.

The Palladian floor plan has been studied by art historians and is easilyidentified.The symmetry between the east and west wings is created by thenorth/south axis.The larger core area in the geometric centre of theconstruction has a complex shape that is the result of cell merging.Windows (like the eyes in the human face) are arranged in even numberswhereas doors are centred and arranged in uneven numbers.

The main entrance is defined by a portico supported by columns whichenhances classical features of the façade that are typical of Renaissancearchitecture.The preferred proportions for the design of rooms, service andcirculation areas are usually rectangular or oblong spaces with 1:2 and 1:3ratios, whereas the main rooms are square or regular symmetrical polygonsor rectangular areas with a 2:3 ratio (a proportion frequently adopted byestablished architects such as Aalto and Siza).The Malcontenta,Angarano,Badoer, Zeno, Pisani, Emo, Sarraceno, Ragona and Polana villas were used ascase studies for rule extraction. Except villa Angarano (3x3), they all have a3x5 grid.


2.2. Grammar system

The original scheme proposed 8 design stages (Figure 1) as does theproposed scheme (Figure 2).The initial stage sets the rectangular boundary(more complex shapes are also allowed by addition processes).The secondstage encompasses subdivision rules. It groups together the two subdivisionshape rules for horizontal and vertical division.Vertical subdivision isperformed in accordance with the symmetrical nature of the design,therefore introducing two division lines. Stage Four, which involves wallthickening, converts the basic outline into two-dimensional representation.This stage deviates from the original grammar since in the latter the wallthickness was derived from the gaps between cells, whereas this grammargenerates an abstract layout then makes it two-dimensional.The fifth stagecreates the entrance, consisting of a section extending from the coreoutwards to create an obtrusion.The definition of functional spaces, which

� Figure 1:

Original Palladian

grammar tree

diagram


had not been previously addressed, was fundamental and these wereintroduced in the sixth stage.Whereas the oblong spaces are mainlycirculation areas, the rectangular and square spaces opposite the façades arethe living areas, and the central space is the social area.The seventh stageinvolved the subtraction of volumes for openings.As previously stated, thewindows are arranged in even numbers and the doors in uneven numbers.Internal doors are usually centred within the circulation area and windowssymmetrically positioned in the façade, taking a vertical centre line as axis.There are different window sizes for the different levels, the larger sizesbeing on the main floor, followed by the top level, whilst the smallerwindows are on the lower ground floor.The design is completed with alabel deletion (a technical stage), which is the eighth and final stage.

� Figure 2:

Proposed Palladian

grammar tree

diagram


3. SHAPE RULES

The system proposed is based on subdivision and the core rule system usedto define the basic layout is composed mostly by division rules that can beapplied recursively. Overall the rule system proposes three types of rules:addition, subdivision and deletion.The first rule represents addition by theinclusion of the outline.This rule proposes the addition of a parametricrectangular boundary shape, based on minimum and maximum acceptableareas, as illustrated (Figure 3).

Subdivision rules include a vertical and a horizontal rule, as exemplifiedin Rules Two and Three.These parametric rules represent the mainoperative process, allow for embedding (applied repetitively inwards oroutwards) and can be used recursively (applied a number of timesconsecutively until the minimum usable space is attained not smaller to 8Vicentine feet as mentioned by Palladio). Subdivision rules respect thesymmetrical design, hence the duplication of division in the vertical divisionrule three.

Following subdivision merging rules apply and, although independent, areintrinsically related. Once the division has been executed, merging is used toarrange larger, complex spaces connecting adjacent rooms.To avoidunwanted space merging, these are applied only to borders, taking theadjacencies and symmetrical relations imposed by labels into consideration.The resulting space is displayed as an enclosed polygon.The west and eastwings will be symmetrical. Deletion rules allow for the creation of complexspaces or a regular polygon boundary. Border deletion is achieved by usingthe forth (horizontal) and fifth (vertical) rules.Wall thickness conforms toPalladio’s specifications.The stone masonry construction used load bearingsheer walls as a tectonic method for envelope enclosure.The thickness ofthese walls is based on know-how and a generous safety coefficient thatmatches the construction grid lines and units.A depth of two Vicentine feetis prescribed for the wall thickness (roughly 750 mm using the metric

� Figure 3: Proposed set of

basic shape rules – subdivision

process


system).The process is described in Rule Six, using an offsetting method.The desired wall centre will sit on top of the abstract layout.Wallintersections are addressed in Rules 7 to 9, which propose the thickening ofT, X, L combinations. Other addition rules add details, such as the entrancefeature (porticos or loggias).These sets of rules are followed by otheraddition rules involving the inclusion of functions.The last set of rulesprovides for alterations using volume subtraction to include openings.Theyinvolve the positioning of windows, which are arranged symmetrically, or thepositioning of doors. Uneven numbers of external doors are centred in thefaçade and internal doors are created to connect rooms.

4. DESIGN GENERATION

In Shape grammars design generation is performed through a processnamed derivation. Derivation describes the generation process in which thesuccessive application of shape rules leads to a final design. Stiny andMitchell’s original grammar showed how a successful design can be achieved,using the example of the derivation of La Malcontenta villa (Figure 4).Thiswas originally built between 1559 and 1560 in Venice and is illustrated inPalladio’s “Il quatto libbri” (Palladio 1997).As a cross comparison method LaMalcontenta was also used for derivation to test and showcase differencesbetween the original and the alternative grammar.The present grammar

� Figure 4:Villa generation –

derivation for La Malcontenta


proposes a more economical use of rules and design process. Despite thedivergences, both grammars contain the same number of stages.The newderivation process proposes 14 steps, using 10 shape rules sometimesrecalled more than once (Steps 2, 5 and 6 using Rule Three, and Steps 3 and4 using Rule Two).The first step places the outline, followed by division inSteps 2 to 6. For division a sequence of rules 2 and 3 used recursively (inthe following order: 3, 2, 2, 3, 3) splits a rectangle into three, or creates avariation of a 3x5 grid in which cells occupy a larger area for futureoccupancy. Step 7 erases the vertical boundaries of the central cell. Step 9offsets the preliminary layout by duplicating lines 2 feet away from eachother and creating the wall placement. Step 10 deals with the intersectionsbetween wall lines and refines corners, refines the wall placement allowingfor an additional dimensionality. Step 11 includes the entrance feature. Step12 proposes functional uses by tagging each room. Step 13 creates openingsin walls with the array or for window and doors. Step 14 terminates thedesign by erasing the labels. Figure 5 shows the derivation process for bothgrammars the original and the alternative grammar.The first uses 12different basic layout rules recursively in 17 steps whilst the last uses 9layout rules in 11 steps.

� Figure 5a:Villa generation

–original grammar using 17 steps

� Figure 5b:Villa generation

–alternative grammar using 11

steps - bottom


5. NEW DESIGNS

Previous shape grammars studies including the original Palladian villas,proposed new sets of solutions possible through the application of theshape rules.The creation of new designs using a shape grammar might be apolemic subject raising deontological issues, especially when addressesarchitectural style developed by others. However existing designs encode alevel of knowledge and know-how sometimes imperceptible, fruit ofexperience and practice in problem solving. By recreating existing corpus ofdesigns, grammars sum much of that underlined knowledge both ingeometry, space, adjacencies and spatial communication.This can then beused to generate new designs that comply with the style criteria and rules.Shape grammars potentiate design exploration.

The Palladian grammar, the first complete architectural shape grammar,proposed 230 new designs combining 10 for villas with a 3x3 grid and 220for villas with a 5x3 grid.To calculate these numbers Stiny and Mitchell usedboth combinatory calculus and colour grammars to illustrate these newsolutions.This was later published in a work entitled ‘Counting PalladianPlans’ by Stiny and Mitchell [14]. From all the examples described andillustrated some are clearly representative of the rule production systemand the Palladian style, others appear to be a repetition of cells and fail toengage as a quality architectural design product.This is also commented bythe authors and expressed in the work ‘An evaluation on Palladian plans’ byStiny and Gips [16].They establish that other values have to be consideredto add aesthetic and spatial quality to some of the villas designed.Noticeably they focus on the need to have a larger room in the central bayand avoid large proportioned rooms to be positioned in extreme locations.This is a post reading of what was rehearsed with the grammar howeverthese could have been easily incorporated into a rule integrating thegrammar itself.

What also is not clearly discussed is the reason why the authors focusedon 3x3 and 5x3 grids either than the fact that this summoned a 3X3 andeight 5x3 villas examples pictured in the ‘Il quattro libri’. However Palladioalso designed and built villas with a 2x3, 3x4 and 5x4 underlying grid, likevilla Barbaro, Cornaro (3x4) Valmarana, Moncenigo and Gazzotti (5x4).Thismeans that potentially more rules could be added and examples can beadded to the new corpus of designs. On the other hand the rules fail toshowcase if they allow parameterizations or if they apply strictly to squareshaped cells which limits the application range but maintains the proportionaspect.This is illustrated in figure 6 which shows the possible layouts forvillas of 3x2 and 3x4 cells disposition.There are 5 possible solutions forvillas of 3x2 and around 80 solutions for villas with 3x4 cell arrangements.Villas with symmetrical layouts and which concatenation process could bemistaken with villas of smaller grids were not included.This means that to


these solutions parameterization can also take place to create differentlayouts, however only room placement was considered.

The alternative grammar manages to propose new solutions that couldbe added to the corpus identified by Stiny and Mitchell. From the newsolutions five new design results constituted the examples showcasingunderlying grids of 2x3. Included in this set is a small villa designed byPalladio. On the other hand several examples were identified to illustratethe possibilities of 3x4 villas. In both cases the following rules weresupervised. Examples that allowed too many concatenation processes to thepoint that these villas could be mistaken by smaller grid sets were scrapped.In the event of rooms with larger proportions, one equally or largerproportioned room, would occupy the central bay.All rooms hadrectangular footprints but the central room could allow also otherconfigurations such as cross shaped,T or I.The north/south axis was thesymmetry axis which meant that west and east wings had mirroredconfigurations.The number of bays over the west to east axis had to bepresented in odd numbers resulting into grids that are (2x3, 3x3, 4x3, 3x5and 4x5), in order to accommodate a central room in the central bay.

The new set illustrated below accommodated the villas also designed byPalladio with 2x3, 4x3 and 4x5 and new examples. Some could be easilyaccommodated among Palladio built examples, others would struggle.Animportant thing to note is that this representation only focus on core baseconfiguration, the spatial proportion still allowed a differentparameterization that most likely would allow some of the examples tolook more feasible.

The prospect of the discovery of a new set of solutions is an excitingone.The reason why the original shape grammar did not explore or supportthe new grids is not clear and any suggestion would be our interpretation.Our analysis into the first ten shape rules, which are responsible for theunderlining grid, show that the current formulation do not support the 3x4and 5x4 grids as seen in villas Gazzotti, Sarego,Valmarana, Montecigo,Cornaro and Barbaro since the concatenation process is limited to aspecific number of cells and the cell manipulation is limited byparameterizations that are not clear. Stiny and Mitchell’s paper does notshow the first steps of derivation using these ten rules however the labelsused (the point and the line) seem to show tight conditions to the scope ofdesign. From our understanding the line symbolizes the external wall andthe design border and the point the possibility to add new cells.We believethis was placed to provide constrains and only allow feasible designs.Theoriginal grammar might support other grids but the concatenation rules donot follow the same principles (for example they do not allow forconcatenating more than 4 cells to generate a ‘T’ shaped room thereforenot allowing the design of villas like Gazzotti or Cornaro).


� Figure 6: New

designs for

Palladian villas

using grids of 3x2

and 3x4


6. COMPUTER TOOL GRAMMAR IMPLEMENTATION

Once the grammar proved efficient and enabled the generation of feasibleresults it was prepared for implementation.The implementation stage allowsfor the clear delineation and quantification of rules.A shape grammar as aformalism and as rule set does not have to be implemented on a computertool. However the computer implementation allows for three things: anaided and closed guided generation process, an enhanced possibility fordesign exploration and a faster and more efficient way to utilize thegrammar.

The computer implementation combines the shape rules, parametricformulation and conditions and actively assists in the complex application ofthe shape grammar. In addition, it reduces errors and secures the generationof solutions.

Several languages and dialects were considered before AutoLISP, editedin VisualLISP.This was selected due to its object-based nature whichfacilitates implementation, using AutoCAD 2012 as a platform.The scriptwas developed in a similar way to the grammar described in this paper(Figure 6). It focuses first on the plan view in 2D and then evolves toencompass the overall modelling of the villa, allowing for immediatevisualisation of the design results in real time.The rules are implementedusing different functions that can be called up recursively if desired and formand function are addressed sequentially.

As described in the methodology section the script is also split into 8stages each stage portraying a different function.

The first Stage (figure 7a) consists on outline definition by placement ofthe exterior perimeter wall.The user is asked to prompt the insertion pointand approximate area.The boundary is set using Palladio’s proportion ratios,between a 1x1 square, and 1x2 rectangle or intermediate appropriateratios.The minimum and maximum areas are calculated and indicated asoutput.The user’s input is optimised to the proportional ratios. Once theoutline is placed, an indicative matrix is inserted using Palladio’s Vicentinemeasurements (1ft ≈0.354m).The dimensions are rounded off to the metricsystem and the proportions conform to classical principles.

The second Stage (figure 7b) permits the user to get involved with thedesign of the interior layout. Subdivision rules allow for horizontal andvertical divisions and the on screen mouse input is registered, with locationjustified to the nearest possible position in the Vicentine matrix. Bothvertical and horizontal rules can be recalled a number of times, restrictedonly by the remaining free space and maximum grid size.

The third Stage is responsible for spatial merging using a cell borderdeletion process.The user has the power to erase border lines to generatelarger rooms and the input is recorded and repeated when necessary tomaintain bi-symmetrical layouts.


The fourth Stage (figure 7c) transforms indicative lines into masonry walldimensions.The exterior walls will present 2 Vicentine feet deep and theinterior walls 1 foot deep.This offset process takes as reference the centreline drawn and reproduces two parallel lines.These lines represent the realwall thickness and will be inserted automatically in separate layers.

The fifth Stage analyses the design generated to this point, positions andsizes the main entrance and rear porticos, which emphases the north/southsymmetry.These entrance elements are sized and placed aligned with thevilla’s central bay.This way the portico and access will direct guests straightto the social areas of the villa.

The sixth Stage punctures openings in walls for doors and windows.Windows are placed symmetrically in each façade arranged to Palladio’sspecification in even numbers. Every facade facing room should preferablyhave an even number of windows or at least one. Exterior doors arearranged along the symmetry axis of each façade in uneven numbers.Interior doors should align with the other openings for division complyingwith Palladio’s rule were mass should face mass and void should face void.

The seventh Stage permits the assignment of functions, accessing theinputs, the design already generated and addressing functional spaces interms of spatial situation (central or peripheral), connectivity (first levelconnection), adjacency and type (living, social or distribution areas). Highlyintegrated spaces such as the core area connect with other rooms aroundto create social areas. Rooms positioned in corners and represented assquares or rectangles with ratios of preferably 2:3, 3:4 4:5, 3:5, 1:2 are livingspaces (studies or living rooms). Rooms between other densely connectedspaces (i.e. with two or more connections) that are smaller and oblong(with proportions of 1:2, 1:3, or 1:4) are distribution spaces (circulationareas, corridors, staircases and ante-chambers).This function labels eachspace and creates the adjacency diagram by connecting the adjacentcirculation areas.The eighth Stage terminates the design by deleting labelsand achieving design completion.The computer tool output is acomprehensive floor plan drawn in AutoCAD with several levels ofinformation.There is a simple abstract design taken from the centre line ofwalls illustrating the basic layout definition.This is recorded in a separateCAD layer and colour for clarity.A more elaborate floor plan is recordedusing different multiple layers segregating the different components ofconstruction.These components also called architectural elements aredoors, windows, external and interior walls and design notes that tag thespaces (figure 7d).The script can run recursively many times for designexploration and comparison of solutions.


� a

� b


� c

� d

� Figures 7 a,

b, c, d: New

Palladian

grammar

computer

implementation


7. CONCLUSION - ANALYSIS OF RESULTS ANDFUTURE WORK

The work described focused on a new grammar formulation for Palladianvillas.This paper presents an alternative grammar for the Palladian villasgrammar, offering a fourfold contribution. Firstly, it demonstrates that twodistinct sets of shape rules can generate the same corpus of designs.Secondly, it proposes a more economical grammar.Thirdly, it addresses andintroduces functions to the grammar formulation. Fourthly, it introduces anddiscusses a computer tool which provides a user-friendly environment fordesign exploration.

Shape grammars are useful stratified formulations that provide supportfor design generation within a particular language.They are an efficientinstrument to describe design.Their use allows for design consistencytested through specific sets of formal and functional rules.As a rule basedsystem, it provides a framework for consistent design generation that fits astyle criteria.

The state of the art in shape grammars focused in diverse architecturalexpressions and manifestations and how to efficiently replicate them.Research has focused on grammars for encoding specific styles andgenerating new solutions within a given style. However, to the best of ourknowledge, generic grammars that encode a range of different design styleshave not previously been inferred. It has been demonstrated here that twoseparate grammars could generate an overlapping corpus of designs.Thedevelopment of such grammars enables tools to be designed that facilitategeneration within the same typology, such as housing. It is believed that thismultiplicity of grammars that allow for similar sets of solutions potentiatedesign and its exploration allowing for creativity.This work is the first stepin this direction. It is part of an enlarged study to encode existing housinggrammars.Theses similar grammatical structure will allow the developmentof higher-level patterns that can be encoded and then customised togenerate new grammars. If these two different grammars with a different setof rules can generate the same set of solutions (recreating a specificlanguage), then a higher-level grammar might allow for the creation ofdifferent languages.This higher-level, generic grammar, once refined, couldencode specific design languages.

Two factors were studied and tuned in this work, form and function or,alternatively, space and occupation.These very important architectural issuesof design were encoded into shape and spatial transformation rules, enablingthe user to create and detail from abstract generic geometries to detailedsolutions, optimised and managed by the use of a computer tool thatincorporates the design knowledge embedded in each rule of the system.The tool developed in this research project was scripted using AutoLISPwhich allows for a universally accepted CAD file format.


These findings have potential uses both in architectural practice anddesign theory. Shape grammars have proved to be efficient tools forexploring design whilst maintaining stylistic consistency. Grammars alsoproved to be a good design tool for both inexperienced designers andexperienced professionals.The proposed grammar provides an alternativemethod for designing Palladian villas.The presented grammar enables thegeneration of three types of solutions: villas designed and built by Palladio,new villas explored and generated by Stiny and Mitchell, and a set of newvillas that were not illustrated or designed by the previous cases. In the caseof the villas previously designed by others it is believed and proved that thismethod is an enhanced process since it allows for a faster derivationprocess while maintaining the design production.

An alternative grammar is relevant if proposes a more efficient way ofachieving the same result and if introduces a novelty.The proposed workpromotes a subdivision process which proves to be more economical usingless derivation steps to achieve the same design solutions. On the otherhand allows for the design of a new corpus of solutions still supported bythe style criteria.

This work constitutes an attempt to generalise the use of grammars andideally create a generic set of parametric rules that can be manipulated andadapted to different contexts.

Future work will address these issues from the perspective of inferring ageneric shape grammar for housing.

ACKNOWLEDGEMENTS

The authors would like to thank Prof. Stiny and Prof. Knight for all thecomments, support and guidance they have provided for this research since2010 at MIT.

A special acknowledgement should be forward to Prof. Phil Steadman toall the precious comments and suggestions at The Bartlett UCL.

A heartfelt thank you to Alaisdair Turner who passed away before thisstudy was concluded at UCL and who co-orientated it.Thsi research wassupported by ICIST and FCT.

REFERENCES1. G. Stiny, & W.J. Mitchell, The Palladian grammar. Environment and Planning B:

Planning and Design, 5(1), pp. 5 – 18. 1978

2. J.N, Beirão, J.P, Duarte, R. Stouffs, Creating generic grammars from specific grammars:towards flexible urban design,: in Nexus Network Journal vol. 13, no. 1, 2011

3. Chomsky, N., 1957. Syntatic structures, Cambridge: MIT press.

4. Stiny, G., 1975. Pictorial and formal aspects of shape and shape grammars.BirkhauserVerlag. Basel, Switzerland.

5. Stiny, G., 1980. Introduction to shape and shape grammars. Environment andPlanning B: Planning and Design, 7(3), pp. 343 – 351.


6. Stiny, G., (2011). What rule(s) should I use? Proceedings in Nexus Conference ‘10.

7. H. Koning and J. Eizenberg, 1981.“The language of the prairie: Frank Lloyd Wright’sprairie houses,” Environment and Planning B: Planning and Design 8, no. 3: 295 –323.

8. Duarte, J.P., 2001. Customizing mass housing: a discursive grammar for Siza’sMalagueira houses.Available at: http://dspace.mit.edu/handle/1721.1/8189[Accessed June 10, 2010].

9. Stiny, G., 1977. Ice-Ray:A note on generation of Chinese lattice designs:Environment and Planning B: Planning and Design, 7(3), pp. 343 – 351.

10. Knight,T.W., 1989.“Transformations of De Stijl art: the paintings of GeorgesVantongerloo and Fritz Glarner,” Environment and Planning B: Planning and Design16, no. 1: 51 – 98.

11. Knight,T.W., 1999. Shape grammars: six types. Environment and Planning B:Planning and Design, 26(1), pp. 15 – 31.

12. Palladio,A., 1997. The Four Books on Architecture, Cambridge:The MIT Press.

13. Hillier, B. & Hanson, J., 1984. The social logic of space, Cambridge, Cambridge Univ.Press

14. Stiny, G. & W J Mitchell, 1978. Counting Palladian plans. Environment and PlanningB: Planning and Design, 5(2), pp. 189-198.

15. Prats, M. 2006. Design exploration in product design: Assisting transformations inpictorial representations. PhD dissertation, Open University, London, UK

16. Stiny, G. & J Gips, 1978.An evaluation of Palladian plans. Environment and PlanningB: Planning and Design, 5(2), pp. 199-206.


Deborah Benrós1, José P. Duarte2 and Sean Hanna3

1University College London - The Bartlett, London, United Kingdom

[email protected]

2Universidade Técnica de Lisboa, Faculdade de Arquitectura - CIAUD;Lisbon, Portugal

[email protected]

3University College London - The Bartlett, London, United Kingdom

[email protected]

Documents

A New Palladian Shape Grammarpapers.cumincad.org/data/works/att/ijac201210404.pdf · Ray Lattices [9] and the De Stjil paintings [10].According to Knight,there are three types of