B4 – Decorative lime rendering, stucco, mouldings, sgraffito

Building
techniques :
B4 – Decorative lime rendering, stucco, mouldings, sgraffito
Country:
Portugal
PRÉSENTATION
Geographical Influence
Definition
Decorative lime rendering, stucco,
mouldings, sgraffito
MOULDINGS AND PROFILES
- Architectural ornamental elements with more or
less accentuated relief, such as:
•
cornices that crown the top of the walls
•
friezes that often underline the level of a floor e.g.
•
framings for openings of doors and windows
- Made with mortar in a thick layer
- Carried out either:
•
Directly on projecting stone elements
•
On a reinforcement fixed onto the support
•
In a workshop then applied
- Profiled with a tool called a templet
- Plays a double role:
•
Display (play of shadows and light,
underlining projecting or relief elements)
•
Protection against bad weather (horizontal
mouldings help water deflect aw ay from runoff
of the façade)
SGRAFFITOES
- Decorative renderings with two, three or four
successive layers
- Realised while scarifying or engraving a mortar a
fresco, mortar is made up of air lime, fine
aggregates and mineral pigments for a possible
colouring in the mass
- Combination of drawing techniques with flat
colouring
STUCCOES
- Coatings with flat or relief rendering, white or
coloured with pigments, usually made of a mixture of
air lime and marble powder.
Environment
In Portugal, decorative renderings (mouldings and profiles, sgraffitoes and stuccoes ) mainly decorate the façades of urban constructions located
in sea side and plain environments. Common, particularly in the south of the country, in the area of Algarve.
Illustrations
General views :
Detail close-up :
This project is financed by the MEDA programme of the European Union. The opinions expressed in the present document do not necessarily reflect the position of the European Union or of its member States.
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B4 Portugal – Decorative lime rendering, stucco, mouldings, sgraffito
CONSTRUCTION PRINCIPLE
Materials
Illustrations
Binding material - origin and availability (form in which it is available )
In Portugal, the binding material in the composition of renderings for decorative elements
(mouldings and profiles, sgraffitoes and stuccoes ) is air lime in paste form.
Aggregate - origin and availability (form in which it is available )
In Portugal, the aggregate used in the composition of the rendering for decorative elements
(mouldings and profiles, sgraffitoes and stuccoes ) is sieved sand.
Aggregate – grading
In Portugal, the grading of the sand used in the composition of renderings for the realisation of
decorative elements (mouldings and profiles, sgraffitoes and stuccoes ) is 0-3 mm.
Dose ratio for finishing coating
In Portugal, the reported dose ratio for the rendering used in the realisation of decorative
elements (mouldings and profiles, sgraffitoes and stuccoes ) is 1 volume of binding material
for 3 to 4 volumes of aggregate.
Tools
In Portugal, the only tools reported for the realisation of decorative elements in rendering
(mouldings and profiles, sgraffitoes and stuccoes ) are the trowel and float.
Trades
Trades, Number of workmen necessary
Not reported.
Construction principle :
general views and details.
This project is financed by the MEDA programme of the European Union. The opinions expressed in the present document do not necessarily reflect the position of the European Union or of its member States.
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B4 Portugal – Decorative lime rendering, stucco, mouldings, sgraffito
CONSTRUCTION PRINCIPLE (CONTINUED)
REALISATION DESCRIPTION
In Portugal : (Text in French)
Pour une description complète de la technique des moulures profilées, se rapporter à la fiche spécifique française B4.
Pour une description complète des techniques des sgraffites et des stucs, se rapporter à la fiche spécifique espagnole B4.
La seule précision fournie par le partenaire portugais concerne l’imitation des carreaux de faïence (azulejos). Elle est généralement réalisée à sec
sur un enduit lisse. Parfois, elle se pratique dans l’enduit frais en y incisant la marque des carreaux.
On ne doit pas exécuter ce travail à des températures supérieures à 30º ni inférieures à 5º.
On applique, comme on l’a déjà mentionné, une ou deux couches de 1 à 2 cm chacune.
Après avoir brossé et lavé le support, le stucateur applique la première couche, il emploie la truelle et la taloche.
La seconde couche est appliquée pendant que la première sèche, ayant un dosage plus important de plâtre, il faudra une plus grande rapidité et
habileté. Le maître stucateur utilise la taloche et la truelle pour appliquer la pâte, l’étendre et la serrer.
Plus tard, après que les parements ont séché, on peint à la chaux.
Les techniques sont celles qui sont courantes pour ce type de travail. L’imitation du carreau en faïence est faite à sec sur un enduit lisse, mais on
connaît des cas où elle est faite sur du frais en exécutant une première incision pour marquer les carreaux sur ce frais. Le stucco est appliqué sur
des moules ainsi que le sgraffité. Il s’agit de finitions artistiques que l’architecture traditionnelle a adopté de l’architecture érudite.
Les techniques du Stucco, sgraffite, sur du frais, à sec et les imitations, étaient en général exécutées par un stucateur ou un maçon spécialisé.
Elle consiste à appliquer des pâtes à base de chaux, avec ou sans pigment, sur une première couche fraîche sur laquelle on procède à l’incision
et par la suite au blanchiment (frais), puis on applique une seconde couche avec un moule enlevé ensuite à sec (sgraffite) ou à l’application de
moules en relief (stucco).
This project is financed by the MEDA programme of the European Union. The opinions expressed in the present document do not necessarily reflect the position of the European Union or of its member States.
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B4 Portugal – Decorative lime rendering, stucco, mouldings, sgraffito
ASPECT, PATHOLOGY
Aspect
Texture, Colour :
In Portugal, the texture of the renderings for the realisation of decorative elements (mouldings and profiles, sgraffitoes and stuccoes ) is reported
smooth or slightly grainy.
The colouring of the renderings is produced either by the materials / aggregate mixture, or by the limewash that covers them. In this case, the
traditional colours are first white, then yellow, blue, red and green.
Ageing Pathology
Linked to the materials and climatic conditions :
In Portugal, the ageing pathologies of decorative elements, made with lime rendering (mouldings and profiles, sgraffitoes and stuccoes ) are
reported as being the same ones as lime renderings smoothed with a trowel or float (see specific card Portugal B2) and limewashes (see specific
card Portugal B1).
Linked to technique :
Not reported.
Maintenance :
In Portugal, no particular maintenance was reported for decorative elements in rendering with lime (mouldings and profiles, sgraffitoes and
stuccoes).
USE, EVOLUTION AND TRANSFORMATION
Use
Types of buildings :
In Portugal, decorative elements (mouldings and profiles, sgraffitoes and stuccoes ) mainly decorate urban houses (one level, with a chimney on
façades, flat roofs...) and particularly houses located in the area of Algarve (south of the country).
All traditional profiles can be found: plinths, base plates, angle ties and anchorings, columns, frames for the openings, friezes profiled, complete
cornices or entablatures...
Know -how is mobilised to a high technical degree, to succeed in creating a noble building with traditional construction, while keeping within a low
budget.
Period when the technique appeared / Period of use of the technique – contemporary or disappeared use
In Portugal, the decorative lime elements (mouldings and profiles, sgraffitoes and stuccoes ) appeared in the 16th century, under the influence of
Italian architecture.
They were however most used during the 19th century.
Disappeared today, except for restoration of old buildings.
Reasons of the disappearing or the modification of the technique :
In Portugal, the disappearing of lime rendering decorative elements (mouldings and profiles, sgraffitoes and stuccoes) is explained by scarcer
craftsmen mastering this know -how, and the high cost of these techniques.
Evolution / Transformation
Materials :
In Portugal, pointless.
Technical aspects :
In Portugal, pointless.
Evaluation of materials and techniques of replacement :
In Portugal, pointless.
This project is financed by the MEDA programme of the European Union. The opinions expressed in the present document do not necessarily reflect the position of the European Union or of its member States.
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