1 Diagnosis and intervention on façades I 1. Constitutive elements and vocabulary 2. Architectural composition 3. Materials, textures and technologies 4. Colours studies and planning 1.1 Horizontal elements • The base or baseplate constitutes the element on which a building is erect. It is therefore the lowest level, conceived in a way to set the upcoming construction. It is always processed with more power elements than upper floors. It is often enhanced with powerful bossage, and false bonds and courses. • The string course splits 2 horizontal levels. It is usually positioned at the same level as the floor or window supports. It is flat, slightly overhanging, with a rectangular section. When the profile is rounded into a curved moulding. it is then called a cordon. • The baseboard is the course running along the base of the wall. It is found even when the first level is processed like a base. • The levels are the different heights of the construction. It is a term used in composition; the level is to the façade what the floor is to the construction. It is delimited by string courses. When there are no string courses, one considers the limit to be the height of the tail-bay.
Transcript
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Diagnosis and intervention on façades I
1. Constitutive elements and vocabulary2. Architectural composition3. Materials, textures and technologies4. Colours studies and planning
1.1 Horizontal elements
• The base or baseplate constitutes the element on which a building is erect. It is therefore the lowest level, conceived in a way to set the upcoming construction. It is always processed with more power elements than upper floors. It is often enhanced with powerful bossage, and false bonds and courses.
• The string course splits 2 horizontal levels. It is usually positioned at the same level as the floor or window supports. It is flat, slightly overhanging, with a rectangular section. When the profile is rounded into a curved moulding. it is then called a cordon.
• The baseboard is the course running along the base of the wall. It is found even when the first level is processed like a base.
• The levels are the different heights of the construction. It is a term used in composition; the level is to the façade what the floor is to the construction. It is delimited by string courses. When there are no string courses, one considers the limit to be the height of the tail-bay.
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1.1 Horizontal elements (follow)
• The entablature constitutes the coping of the construction. It is made of three elements, cornice, frieze, and architrave (the architraved cornice cancels the need for a frieze.)
• The cornice is the coping of the entablature. It is most often made of a rail- shaped by a round moulding, for example an ogee or a cyma - and a drip designed to stop rain runoff.
• The frieze is under the cornice. It is a non-moulded horizontal strip, sometimes decorated with a painted or sculpted pattern.
• The architrave is the lower part of the entablature. It represents the lintel, which spans between two supports (column, pillar…). In a decorative entablature for a façade, it is very much like a moulded string, a belt, which no longer spans or covers empty spaces.
1.1 Horizontal elements (follow)
• The attic head constitutes the coping of the construction. The height is much lower than that of other levels, and it is separated from the other elements by a usually much larger moulding (cornice, frieze) than the actual attic level. If there are no clear moulding, a floor which is much lower than the others is simply called a mezzanine floor.
• The entresol is a mezzanine floor just above the ground level, usually smaller in height, was elements are usually included in the first level (the base level).
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1.2 Vertical elements
• The bay or section, in common architecture, refers to the superimposition of bays on a vertical axis. The lateral limits of a bay are the axis of the pier (or the needling and axis of the first pier)
• The pier refers to the wall between two bays openings of the same level.
• The needling is the panel between the angle of the building and the first lateral bay.
• The full bay is the panel between two bays of a same section.
• The cornerstone is the vertical linking element between two walls making up an angle. It is made with superimposed heading courses. The materials used are usually different or larger than the rest of the facing (when false architectural elements are implemented, with rendering or painting, the same characteristics are applied to differentiate corner elements from walls). The main elements are usually toothed: toothing describes the alternate laying of short and long elements, thus creating a tooth pattern.
1.2 Vertical elements
• The jamb (door) (post for windows) is a vertical element secured into a course wall or partition. Toothing can be applied.
• The pilaster is a vertical support, a rectangular element, slightly more protruding than the facing. It usually consists of the base and always includes a capital.
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1.3 Façade terminology
•The bay (opening) refers to any opening in a wall, the bay element includes the frame. A blind bay or blind arcade (an opening from the ground up and surmounted by an arch) are also considered as bays or openings.
•The niche is considered an opening. The backing is flat or concave.
•The lintel is the element that covers an opening. It can be flat or arched. It is monolithic, that is to say, one solid element.
•The band moulding is an arch which is flat on the underface. It is made with arch stones; the centre stone is called a keystone. When used to cover an opening, the band moulding replaces the monolithic lintel. On façades, bay covering is often constituted of three parts: two lateral transomes, laid on sidewall elements, with the central keystone. When a keystone goes beyond the main lines of the Arch, it is called “passante” [French word], (towards the top) or hanging (towards the bottom). When it stands further out than the facing it is called overhanging or protruding.
1.3 Façade terminology (follow)
• The support is the lower horizontal elements of an opening or bay (window, fake window, but not the door). It can be flat like the wall or protruding. When protruding, it can be moulded with elements protruding further out than the column, jamb or architrave of an opening.
• The column is a loadbearing element for the covering of an opening. Support columns are also the lateral limits of piers. In façade terminology, the column facing parallel to the band moulding is called the jamb. The return thickness, from the arris to the opening, is called a vertical side.
• The frame (or casing) is the frame of an opening on the facing of a wall. It can be moulded. When the frame is decorated with an offset or projection, it is called “à crossettes” [French word].
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1.3 Façade terminology (follow)
• The basement of the window (or apron) refers to a wall panel between the floor and the support of an opening, as well as between the horizontal jamb liners. This part of the wall carries the woodwork, and is often thinner and lighter than the façade wall.This element is invisible from the outside, but can be indicated on the façade by panel work or a slight projection of a moulding.
• The transom, in woodwork, refers to a sash superimposed to the main opening element, whether mobile or not, with or without windows, it is separated with a horizontal bar (a transom bar).
• The oculus is a round window (when there is woodwork), or aperture (when there is no closing device). In a dormer window it is called a bull's-eye.
1.3 Façade terminology (follow)
• The Mullioned window is an opening, divided vertically by a mulliondevice, a narrow fixed woodwork or masonry. It is often re-divided horizontally with the same material, it is then called a casement window. (the mullion and horizontal element create a cross shape).
• The Pediment is a low-pitched triangular head or cap, triangle formed by sloping roof and horizontal cornice, shaped with a moulded frame (cornice moulding: drip and rail). Found on the front or centre of façade elements, above openings: doors or windows.
• Broken pediments, are pediments that are interrupted before the tip of the triangle. Other variations of the pediments are interrupted in the centre of the horizontal cornice. To make an arched pediment, one replaces the two sides of the triangle with a single arch.
• The balustrade is made of a base, and a line of balusters crowned with a continuous rail. It can either be a balustrade used for person security or as a decorative element of the entablature.
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FACADE VOCABULARY - Renderings
• In the French tradition, outstanding civil architecture uses noble materials: a variety of stones and marbles. This lavish and monumental architecture constituted a model for a wide range of constructions, from common civil buildings to modest constructions. Rendering plays a major role as a substitute for stone.
• A first category of rendering can either: - look like stone, imitating its aspects faithfully, even to the point of texture imitation, - reproduce the patterns of its elements -outlining courses, mouldings, angle stones. In these two cases there is an explicit and obvious reference to stone architecture. This reference can go from hyper realistic to a more discrete outline.
FACADE VOCABULARY – Renderings (2)
• A second category of rendering no longer refers to stone construction models and becomes a fully expressed façade material. Rendering can be a simple coating used for technical reasons, on storage annexes or buildings where decor is not an issue for the owner. But rendering can also be used, almost always in urban environment, as a means to display a more refined architecture. In this case, rendering is used in a design spirit, to reshape the façade, displaying the construction techniques of a building, exploiting a more or less elaborate decorative art. This design — which calls upon drawing, textures, and colour — refers to specific construction elements (loadbearing constituents, openings) and outlines the composition of a building: patterns, divisions and proportions.
• Observing the renderings of the building, as well as the way they constitute or enhance profiles and mouldings, will bring forth the architectural intentions of the builder. Contrary wise, a building which has lost its rendering seems deprived of identity, stripped from any signs of its civil role.
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2 Architectural composition
• Partition is meaningful• Elaborated yet modest, hierarchically
1. Intervening on a façade project2. Pathology, diagnosis and specifications3. Practical exercice case study
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FAÇADE DATA SHEET
Practical exercice case study
• What do you observe on this picture and its detail?
• List and describe succinctly all the solutions that could be proposed for a good presentation of this façade?
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Introduction to façade pre-diagnosis
- A preliminary diagnosis: to make a first evaluation of the condition of the building and defining the various fields and tasks that could be involved in the project, during this first visit.
Note : a general principle to have in mind :
• No prescription should be done without a good understanding of the causes and origins of the decay
Twelve rules for the owners, for efficient maintenance
1 Maintain the roofing in good condition2 Clean obstructed gutters and repair all cracks3 Fill the small cracks and the opened pointing4 Protect wooden constructions against humidity5 Paint all iron components regularly6 Protect the building against all damaging animals 7 Avoid all mosses and plants8 Aerate all the rooms9 Control regularly all technical installations10 Have the thunderstorm protection inspected every year11 Avoid extensive use of the building
