Cultura e Scienza del Colore - Color Culture and Science


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Cultura e Scienza del Colore - Color Culture and Science | 06 | 2016 ISSN 2384-9568

1Giulia Pellegri 
pellegri@arch.unige.it

1Department of Architecture and 
Design, University of the Study 
of Genoa, Polytechnic School 

Chromatic and decorative 
planning choices: 
geometry, knowledge and survey   

ABSTRACT
This study wants to highlight the complex planning  and technological/procedural choices in 
order to address all types of painted façades’ intervention: conservation, maintenance and 
restauration. 
The major difficulties in surveying the historical façades’ painted decoration, depend mainly 
on the conservation conditions of the same, on the building support, on the degree of legibility 
of compositional scheme, on the cultural sensitivity of the researcher and on the objective 
knowledge of the different types of plastics and painted ornaments of historical architecture.
The methodology includes: study of historical treatises on the art of drawing of the architectural 
orders, study of historical treatises on geometry (study of shadows), study of the theories of color 
and the repercussions on the current methodology survey painted decorations with the direct 
method and computer graphics.
So the complex research is to ensure through finding colors and decorative types of individual 
cases and of their building as a whole understanding the rules and the methods ‘ use of decorative 
repertories, of colors of materials and of the execution techniques of  compatibility  historical /
figurative design.
The planning choices regard principally  the two components:

• compositional structure  and decorative façade
• color values of all the elements of the façade.

KEYWORDS
Survey, Colour, Decorations, Geometry, Planning, Digital 

CITATION:  Pellegri G. (2016) ‘Chromatic and decorative planning choices: geometry, knowledge 
and survey’, Cultura e Scienza del Colore - Color Culture and Science Journal, 06, pp. 61-69, DOI: 
10.23738/ccsj.i62016.06

Received 5 February 2016; Revised 22 September 2016; Accepted 23 September 2016

Giulia Pellegri is associate Professor in Drawing scientific disciplinary sector, Department of Architecture and Design -Polytechnic School 
of Genoa-Italy , and  member of the Architecture and Design Graduate School. Research interests: Urban and Environmental Survey, Drawing 
Representation of analogic and digital techniques, Geomatics aimed to the Conservation and Restoration and Colour Measurement Systems.



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Cultura e Scienza del Colore - Color Culture and Science | 06 | 2016 | 61 - 69   

Pellegri G.      

ISSN 2384-9568

DOI: 10.23738/ccsj.i62016.06

1. INTRODUCTION

This study wants to highlight the complex 
planning  and technological/procedural choices 
in order to address all types of painted façades’ 
intervention: conservation, maintenance and 
restauration. 
The major difficulties in surveying the historical 
façades’ painted decoration, depend mainly on 
the conservation conditions of the same, on 
the building support, on the degree of legibility 
of compositional scheme, on the cultural 
sensitivity of the researcher and on the objective 
knowledge of the different types of plastics and 
painted ornaments of historical architecture.
The painted decorations often follow exactly the 
compositional schemes of orders in architecture 
but, depending on the historical, economic and 
cultural period different types of decoration 
can be distinguished such as: architectural 
elements, ranging from the simple to the 
most complex structural and spatial moldings 
partitions; architectural elements intermingled 
with individual figures located in front of the 
prospective apparatus or in other cases inserted 
into them, in order to assume themselves the 
role of structures; figurative subjects inside 
large panes, historical or mythological scenes, 
allegorical figures or personification of the 
political and military power with their symbolic 
meanings.[1] 
The knowledge of the treatises, of the study 
of historical texts on the “ornaments” and of 
the notions of teaching about the possible 
compositions of the architectural decorations 
and their proportions with the study of shades, 
are  fundamental  for  the  purposes of painted 
decoration survey and  conservation.
On this basis this study analyzes the relationship 
between the color and the drawing in the context 
of external finishes of the historical façades, how 
much the drawing defines the color or vice versa 
how much color composes the drawing through 
the balance among color fields and combinations 
of hot and cold.
It’s fundamental to highlight how the drawing 
and the color are related to the potential 
conditionings that may accentuate, mitigate, 
reduce or differentiate the individual elements, 
making a proportionate or perceptually distorted 
building, through the research about the drawing 
of the patterns and the visual perception of 
painted decoration. This research analyzes the 
drawing of the shadows through the study of 
the shape, of the depth and of the thickness, 
the painting technique of chiaroscuro and the 
proper use of color. Is drawing color and/or is 
the color shape and so drawing? This question is 
often at the base of the problem of the study and 
of the revival of the façades’ painted decoration 
and it concerns many issues that arise as the 

fundamental approach to the problem. This 
paper proposes a methodology for the research 
aimed to investigate the relationship among 
drawing, color, plastic and painted façades’ 
decoration.  
The methodology includes: study of historical 
treatises on the art of drawing of the 
architectural orders, study of historical treatises 
on geometry (study of shadows), study of the 
theories of color and the repercussions on the 
current methodology survey painted decorations 
with the direct method and computer graphics.

2. DRAWING FATHER OF THE ARTS: 
    ARCHITECTURE, PAINTING, 
    SCULPTURE  
    

Che cosa sia disegno, e come si fanno e 
si conoscono le buone pitture et a che; e 
dell’invenzione delle storie.
Perché il disegno, padre delle tre arti nostre 
architettura, scultura e pittura, procedendo 
dall’intelletto cava di molte cose un giudizio 
universale simile a una forma overo idea 
di tutte le cose della natura, la quale è 
singolarissima nelle sue misure, di qui è che 
non solo nei  corpi umani e degl’animali, ma 
nelle piante ancora e nelle fabriche e sculture 
e pitture, cognosce la proporzione che ha il 
tutto con le parti e che hanno le parti fra loro 
e col tutto insieme

(G. Vasari, Le vite de’ più eccellenti pittori, 
scultori e architettori, vol.I Della Pittura, cap. XV, 
1550,Edizione Giuntina)

Vasari sees the technique of the art all enclosed 
in drawing where we can find the values 
of ideation, introducing a first classification 
of the drawing techniques according to the 
degree of complexity. In his treaty, Vasari 
clearly distinguishes sketches, intended as hint 
touches, from draws, intended as a defined 
section with profiles and contours essential for 
the architecture, sculpture and painting. [2] But 
even in The Book of Art, 1390, Cennino Cennini 
places the painting second only to the science: 
“The foundations of the art are drawing and colour”,   
highlighting a good amount of techniques and 
supports of the art. In the fifteenth century 
treaties pay more attention to the “linear 
drawing”, which allows a greater detachment 
from reality and therefore a greater focus on 
pure composition. The Renaissance treatises 
emphasize the importance of drawing, seen as 
the main skill required for anyone who aspires 
to become an architect. Sebastiano Serlio - 
Tutte l’opere d’architettura, et prospectivae, 1538- 
was one of the most popular books during 
the sixteenth century; the beginning of Book II 
observed that 



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Chromatic and decorative planning choices: geometry, knowledge and survey

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“the perspective would be nothing without 
the architecture and the architect would be 
nothing without the perspective.” (Figure.1) 

Serlio pointed out how all the greatest architects 
of his time, Bramante, Raffaello, Peruzzi and 
Giulio Romano, had started out as painters. 
In the new division of labor that took shape 
during the fifteenth and sixteenth centuries, 
what constituted a new genus of architects, 
regardless of the construction industry, was 
their mastery of drawing. This made it possible 
to separate their activities from construction and 
design, due to the link between the drawing and 
the geometry made possible by the new science 
of perspective. This period bound architecture 
to abstract thinking, guaranteeing the status 
of intellectual labor rather that manual. Within 
the new division of labor, the drawing was the 
only part of the process of building production 
on which the architects maintained an absolute 
and exclusive control.
Leon Battista Alberti reinforces this idea by 
asserting that “it is possible to draw all forms in 
the mind without any recourse to the material.” 
On the one hand the drawing was entrusted with 
the vital responsibility to convey the idea from 
the mind of the architect to the created building , 
but on the other hand the drawing suffered from 
the disadvantage of being always considered 
inferior to the idea and, finally, to degrade it. In 
practice, this tension was resolved generally 
overestimating the accuracy of the orthogonal 
projection and exaggerating the falsity of 
perspective. Alberti was the first to do this:

“The difference between the drawings of the 
painter and of the architect is as follows: the 
first seeks to emphasize the importance of 
the objects in the painting through the light 

Figure 1 - S.Serlio, Tutte l’opere 
d’architettura, et prospectivae, Venice, 
Ed. 1600

and shade by thinning the lines and angles; 
the architect rejects the light and shade , 
but he gets its projections by the plan and, 
without altering the lines and keeping the 
actual angles, reveals the extent and shape of 
each prospect and of every side.” [2]

A very interesting graphical approach is the book 
“Perspectiva pictorum architectorum” by Andrea 
Pozzo, Romae, 1693 with the attached tables 
of the prospective study from different points of 
view and the study of light and dark, particularly 
important for the technique of trompe l’oeil.
A. Pozzo doesn’t limit himself to writing a 
theoretical treatise, but he has the merit of 
teaching the way to put into perspective all the 
architectural drawings, to use both for painters 
and for architects,

 “the deception of the eye, can be achieved 
only through a knowledge and a thorough 
study of the perspective technique. This is 
the ambition of my book “(so A. Pozzo writes 
in the dedication to the future Habsburg 
Emperor Joseph I).

The first part is about the basic canons of 
matter, the second part is about the operational 
procedures for drawing in perspective domes, 
altars, fountains, stairs and other architectural 
elements. The treaty is placed in the established 
tradition of architectural treatises such as 
Palladio, Serlio, Vignola and Scamozzi. The artist, 
however, differs from these illustrious names, 
elaborating a treaty that explores the art of 
perspective in all its variations and applications: 
architecture, painting, theater, ephemeral 
apparatus. The Jesuit artist can without doubt 
be considered the supreme representative of the 
quadraturism representation .



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Pellegri G.      

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DOI: 10.23738/ccsj.i62016.06

The quadrature’s painters, making use of 
knowledge about the geometric perspective 
and the techniques of pictorial representation 
on large wall surfaces, reproduce spectacular 
spatial effects through the drawing of 
architectural elements real or imaginary.
In the fifteenth century the interest of painters, 
sculptors and architects focuses on the problems 
of linear perspective and in this context there are 
the first symptoms of the distinction between 
painting figures and architecture. 
The passage of the decorative painting, from 
ornamental architecture to connection with the 
depicted scenes and, later , to the development 
and completion of the building structure itself, 
is marked by the application of the principles of 
linear perspective to architectural frameworks 
and architectonic backgrounds .
In the late seventeenth-century Rome, Pozzo 
represents the top of Baroque visual culture 
that stems from a bold artistic experimentation 
exalting, with unpublished proceedings, the 
allusive power inherent in the image space.
(Figure 2) [3] With the drawings of the treaties 
of the eighteenth and nineteenth centuries, the 
study and the use of shadow confirm, unlike 
Alberti, one of the foundational aspects of the 
drawing representation. The “draw” achieves the 
highest academic reputation in the nineteenth 
century, thanks to the lessons imparted by the 
academies in Europe, where the watercolor 
technique was widely considered to be essential 
to give a more incisive and popular character 
to the performance, because, unlike the linear 
perspective, which presupposes an intellectual 
process in the understanding of the design, and 
the watercolor, and the use of shadows are an 
expression of easily understandable language 
forms.

Figure 2 - Pozzo Andrea, Perspectiva 
pictorum architectorum , Romae, 
1693

3. CONCLUSION: 
    SURVEY -  DRAWING - APPLICATION

For the methodological  approach, the survey  
plays a vital role in reaching the historical/
critical and  formal knowledge both quantity and 
quality aspects of the historical fronts’  finishes,  
ranging from those historical, figurative and 
perceptual  to the technical ones reaching  the 
valence of incontrovertible documentation of the 
state of art , and tool of guidance and control , in 
order to avoid arbitrary choices.
The critical survey, beyond the measurements 
and related graphic representations through 
plans, sections and elevations, becomes 
fundamental to address the typological 
study of the urban fabric i.e the processes 
that characterize an urban organism in the 
succession of its evolutionary phases.
It’s necessary to read the architecture as the 
result of a multiplicity of interventions  in the 
realization of urban spaces highlighting the  
actual development through the basic building, 
the remelting and the  superfluous .
A fundamental study for the achievement of 
quality is the decorative historic structure, 
even  in the simplest cases , always arises 
in interrelation with the overall architectural 
structure to prevent figurative distortion and 
ungrammatical remakes. So the architectural 
survey of the fronts with the overall decorative 
structure, must be articulated at different 
scales. The critical survey together with the 
graphic description a method of search about 
the fronts’ characters is the  main cognitive tool 
of quality  survey and secondly  the dimensional 
proportionate scheme in order to distinguish 
and describe the decorations, the types and the 
materials, from the sketch to the development 



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Chromatic and decorative planning choices: geometry, knowledge and survey

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of the relationship between architecture and 
decorations  (architectural order –color) .
So the complex research is to ensure through 
finding colors and decorative types of individual 
cases and of their building as a whole 
understanding the rules and the methods ‘ use 
of decorative repertories, of colors of materials 
and of the execution techniques of  compatibility  
historical /figurative design .
The planning choices regard principally  the two 
components:

1 - compositional structure and 
decorative facade
2 - color values of all the elements of 
the façade.

The analyses have a sense and a consequence 
design with the study of the  decorative color 
-treatment of the facade from the simplest 
monochrome to the most complex types with 
painted polychrome decorations extended 
to all part of the façade through direct and 
instrumental tools (measurement, photography, 
infographic Photo rectifier with shields and 
processing of contrast..).
The study of the painted decoration, as mentioned 
above, can’t be tackled without the depth and 
knowledge of the treaties, architectural orders, 
the study of descriptive geometry and the rules 
and applications of the drawing first and of the 
color then. 
Particularly interesting for the purposes of 
restauration and/or the project of facades’ 
painted decoration, are: Rules for Drawing the 
several Parts of Architecture Gibbs, James London, 
1736: The City and Country Builder ‘s and Workman 
‘s Treasury of Designs or The Art of Drawing and 
Working the Ornamental Parts of Architecture 

Figure 3 - The City and Country 
Builder ‘s and Workman ‘s Treasury 
of Designs: Or, The Art of Drawing 
and Working the Ornamental Parts 
of Architecture Langley, Thomas 
London, 1740

Langley, Thomas London (Figure 3), 1740 and 
The principles of architecture Nicholson, Peter 
London, 1795-1798 (Figure 4), that are actual 
implementation of practical manuals about 
architectural decoration and composition  of the 
façade.
At first they follow the practical and organic 
characteristics; then process in an aesthetic 
sense without losing distinctive character, until 
in a final stage of stylistic development break 
down sharply from the element structure; to 
give a rhythm in architectural compositions, 
emphasizing the wealth of some areas and 
aesthetically changing relationships. The first 
type of decorative expression is inherent in the 
materials, the design is obtained by processing 
of surfaces - flat, rustic ashlar, and imaginative   
forms   of the   Renaissance.   The   aesthetic   
transfiguration   of the architectural elements 
is due to two methods: geometric procedure 
and reproduction of the essential aspects 
of the nature both from the point of view of 
the design of that of color. The application of 
stucco depicting the elements of nature and 
the architectural orders in the Renaissance has 
extensive use of decoration on the façade, while 
in the seventeenth and eighteenth centuries 
are used in order to free decoration from 
any constraint other than that of the general 
architectural framing.
The first of these applications simulate the 
architectural elements of stone (frames, ashlars, 
shelves) or mimic, in the more strictly ornamental 
expressions, garlands, shells, drapes, or 
foliage. Then they gradually assume fantastic 
character, which only remotely reminiscent 
of ancient models, in broken curves frames, 
twists, plaques, flourishes of any kind. The 
color was almost constantly used, sometimes 



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Pellegri G.      

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as indispensable attribute of the form, or with 
overlay colors to construction elements, or 
with the coating of paint entire wall surface, or 
with the combination of different polychrome 
materials.[4]
The first step is to define the decorative signs 
of the façade in proportional relationship to 
the study of the component parts, identifying, 
at the same time, the base color and then 
the ornaments’ color. For this reason, the 
composition of the façade, simple or complex, 
takes into account the primary structures of 
the building i.e. the vertical and horizontal ties. 
(Figure 5)
The approach exemplifying the types of 
decorative facades led to the identification of 

three basic types: Monochrome Bottom front 
and basement with simple decorative elements 
(frames) - Monochrome Bottom front with 
monochrome base or ashlars with decorative 
elements or simple (and frames antheridia) 
and Monochrome bottom front with base 
monochrome ashlars or complex with decorative 
elements (frames- antheridia-pilasters-panels 
and other decorative elements). The use of 
bringing back in front the structural nature of the 
building and especially the highlighting of the 
main floor has caused in the visual-perceptual- 
formal habit, that has conditioned the decorative 
design choices to the point of incorporating 
two floors in a decorative order so to donate 
luxuriousness that internally does not exist.

Figure 4 - (1-2-3-4) The principles of 
architecture Nicholson , Peter London, 
1795-1798, (5)- Panel of Study at 
the Academy of Fine Arts in Genoa. 
On the right study on compositional 
decorative pattern for the Color 
Project in Savona (Italy) through 
Infographic Photo rectifier with shields 
and processing of contrast.

Figure 5 - Survey and drawing 
representation of the painted 
decoration of facades.Historical 
Centre of Genoa. 



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The decoration is also meant to recreate a 
harmony of “lost” proportion, adapting the 
decorative elements to spaces.
The wide panorama of case studies, which 
emerged at the meeting in Rome “Coatings, 
Colour, Colouring of Buildings and Historic” 
in 1984, sponsored by the Ministry of 
Environmental, exceeds the two extreme 
positions of restauration  all short  , or restore 
an outright original color, which often no longer 
has any acknowledgment nor with the current 
reality, nor with more recent historical memory. 
[5]
Where overexposed theories do not find 
possibilities of application, to attain an 
appropriate harmonic relationship of the colors 
to be used, we should refer to the theory of 
colors applied to wall surfaces that receive the 
color. In this case, by referring to the color table, 
the design directions want to highlight a line of 
intervention in the choice of the chromatic colors 
of the facade in order to avoid that between the 
painting of two neighboring buildings there is a 
chromatic saturation deviation exceeding 15% 
and of more than 10% color brightness. [6] 
(Figure 6)
In the treatise Grammar of Ornament, O. Jownes 
describes the use of colors connected to the 
plaster and painted architectonic decoration 
(proposition n. 14-15-16-17-18).  [7]
A right approach to the choice of colors in the 
painted decoration of the façades is in the 
awareness that it is influenced by the ratio 

of the proportion between the parties given 
by perception especially by the contrast of 
simultaneity [8]: definition of the decorative 
composition and identification of the different 
color fields, through the study of individual 
components and of the relationship between the 
color of light and shade.
The planner, once identified the decorative 
“types” arises the problem of verifying the 
wanted prospective study perceptual in relation 
to the environment and to the visual quality 
of the façade. The restoration of the painted 
decoration is the result of an accurate survey 
of the historical traces in order to reproduce, as 
closely as possible, the  spirit   of   the   original   
work.      
The direct survey, the drawing from life, the 
investigation, also photographic, from the  
panoramic to the details are the early steps 
of analysis aimed to color plan of painted 
facades. The compositive architectural façade 
was created as an expression of the lexical 
composition of the aggregation highlighting 
the architectural building elements and their 
interconnections. From drawing to wire, the yield 
of shapes, surfaces, contours through tones and 
graphic textures, up to a constant enrichment 
of personal stock of signs and techniques, 
everything becomes essential to understand 
an architectural detail, the relationship 
between architecture and urban configuration 
or landscape. Drawing from life is depiction, 
critic visualization, communication, but this 

Figure 6 - Synthetic scheme of urban 
and environmental survey in the ambit 
of the research agreement: The an-
cient center of Albenga, analysis, sur-
veys and profiling aimed at recovering 
and restoring the color value. 2012-
2013 Scientific responsible G.Pellegri



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Pellegri G.      

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DOI: 10.23738/ccsj.i62016.06

obvious assertion is precisely the most difficult 
to achieve, because, after a long time, you 
have the powers of observation and execution 
and the readiness of reading the real meanings 
that allow you to translate the observed reality 
in an image rich in meaning and can convey to 
those who view the drawing, the relationship 
established between reality and draftsman.

Just as a subjective model of reality always 
different and changing, still-life drawing is the 
result of a complex set of shape analysis, for 
immediate application of geometric concepts, 
of tonal evaluation, of the characters’ selection, 
knowledge of graphic techniques and, of course, 
of critical consciousness.
In practice drawing from life allows us to 

Figure 7 - 1 – Photograph of detail of 
a painted façade  in Genoa Corniglia-
no; 2.Infographic Photo rectifier with 
shields and processing of contrast; 3. 
Development by chromatic variation 
curves of contrast; 4. Color correc-
tion automatically by algorithms, clip-
ping colour channels to increase the 
contrast and correct colour casts; 5 
a-b-c-. Last Steps with the addition of 
algorithmic processing aimed to find 
the bright and the dark to use as light 
and shadow

Figure 8 - Exercise of Painting 
Façades Decorations at the Academy 
of Fine Arts in Genoa and the typo-
logical scheme of the color  project 
section for the painted decorations of 
the ancient center of Albenga



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Chromatic and decorative planning choices: geometry, knowledge and survey

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observe how things change depending on the 
brightness, the distance from the point of view 
and proximity to other elements; it allows us to 
understand that the technique must not prevail 
on observation and transcription of meanings.
This research highlights how the images 
acquired during the photographical survey are 
altered by computer graphics systems first with 
photo- rectifier and then with shields contrast, 
with the study of tone and  of colorimetric curves 
in order to identify the different color tones.
(Figure 7)
At Academy of Fine Arts in Genoa, the students 
approach to the decoration of façades through 
the application of the drawing and the color 
theories painting panels starting with sketches 
on paper and proceeding with the fresco 
technique. From drawing to wire it goes to dust 
and then to the pave of the color tests with 
the same procedure with which we apply the 
chiaroscuro on painted façade, starting with the 
drafting of the basic colors. In the first phase 
are applied the 1st dark, the 1st light and the 
first shadow on the bottom so as to make three-
dimensional drawing.
Then you apply the 2nd dark (for a darker tone) 
and the 3rd dark (still a darker tone), the relights 
(a lighter tone) and the second drop shadow. The 
final touch is given by a dark reddish-brown that 
is used to give more depth (Figure 8).

FUNDING

This work was supported by the Search 
agreement made between the municipality of 
Albenga, the Industrial Union of Savona and the 
Department of Sciences for the Architecture, 
University of Genoa, Italy, Responsible Scientific 
Giulia Pellegri. 2011-2012 Color Project of the 
historic center of Albenga.

CONFLICT OF INTEREST

Potential conflicts don’t exist.

BIBLIOGRAPHY

[1] G. Rotondi Terminiello, “Le facciate dipinte a Genova: 
note per una metodologia di restauro”, Ministero per i Beni 
e le Attività Culturali - Bollettino d’Arte, suppl. n.6, Roma, 
1984.

[2] G. Vasari, “Le vite dei più eccellenti pittori, scultori e 
architetti”, Edizione del 1568, Firenze. 

[3]  F. Di Stefano, “L’effimero e l’illusione in età barocca”, 
2011, e-Book per l’arte.

[4]  V. Fasolo , La decorazione, Enc, Treccani, Ed.1931

[5]  P.Falzone (a cura di), “Colore, Architettura, Ambiente”, 
Kappa Ed., Bologna, 2008.

[6] G. Pellegri, F.Salvetti,  “Analisi, Rilievi e Schedature dei 
Valori Cromatici del Centro Antico di Albenga. Il progetto di 
conoscenza e le fasi operative”. Alinea Ed., Firenze, 2012. 

[7] O. Jones, “The Grammar of Ornament”,  Londra, 
Beenard Quaeitch, 1868.

[8] J. Itten, “Arte del colore. Esperienza soggettiva e 
conoscenza oggettiva come vie per l’arte”, Milano, Il 
Saggiatore,1965.