Generations of architects have debated and examined which form of illustration is most suitable for conveying an impression of their building to themselves and to different groups of people. Looking at the depictions of architecture as described in contracts and the basic forms of depiction used by architects work we find the following range of drawings: site plan, floorplan, elevation, section, detail, perspective and then, less commonly, axonometric. Learn more...
These aspects can be roughly broken down into the following architectural categories: the urban situation, the function, the construction, the proportions, the configuration of building volumes, the way the building parts fit together, and the materials used in the building. This applies to technical drawings made to a particular scale as well as to freehand sketches, which at the start of a design are generally made without any scale. When the design becomes more con-crete or when the planning commission is based on an existing building, the freehand sketches also employ a scale. You discover which drawing at which scale is ideal for conveying the intended content through indi-vidual experience and by drawing regularly. Designs should be continu-ally developed and examined in several types of drawings.
Site plan, floor plan, section and elevation are planar depictions, i.e. simple projections. They are not experienced in reality, as the elevation, for instance, is an “unrealistic” drawing, made at right angles to the build-ing from an infinite distance. We experience a real building very differ-ently. The site plan and elevation describe the exterior of a building, while the floor plan and section provide mostly information about the internal configuration of the building. Axonometric projections are based on pla-nar depictions but also show the third dimension, height. Perspectives are central projections and are based on one or more vanishing points.
Pictograms are a special case. These are symbolic graphics that attempt only to convey the design idea or design variations. They must not be based on any of the drawing types referred to above and must not provide any concrete information or data about the design. The drawn form of the pictogram is very free, but generally extremely clear in graph-ical terms. They do not use any scale.
Sketches of different projections: floor plan, section, elevations (developed design)
Pictograms of different facade versions (conversion of an existing high-rise)
The largest scale drawing of an individual building or complex of buildings is the site plan. The site plan shows the location of all building parts on the site and its immediate surroundings, whose surface areas are also shown. The building that is the subject of the design is shown as a top view. Site plans are generally drawn at a scale of 1:500, at earlier design stages and in larger building projects also at 1:1000.
It makes sense also to show the immediate surroundings of the planned building. These can include neighbouring buildings, vegetation or infrastructure elements. Site plans often contain legends, levels (height above sea level) and arrows that indicate entrances or circulation. North is generally to the top of the sheet, a north arrow (or pointer) should always be used. The building should be drawn in such a way that it stands out clearly from the surrounding developments. This can be achieved by heightening the contrast, by using thicker lines, or by the use of colour or surface textures. The site boundaries are indi-cated with a dashed line.
A floor plan is a horizontal cut through a building. Architects always look down from above, that is to say, a cut is made through the building and everything that can be seen below the line of the cut is shown. This line is chosen so that all the openings and the circulation systems can be seen. The floor plan shows the arrangement of rooms on the different floors, each floor being drawn separately. Floor plans reveal spatial sequences and functions. Sketches of ground floor plans should show the nature of the surrounding area of the site.
TIP: If the shape or position of the further floors of the building differs from the floor plan shown it makes sense to indicate them using full, dashed or dotted lines (see Chapter Tools and techniques, Lines and the instruments for drawing them).
A floor plan takes shape through the arrangement of rooms, sorted by colour according to their function.
Dark or black-coloured walls outlining white rooms are one of the principal characteristics of a floor plan sketch. They reveal the building typology, separate rooms from each other, or indicate the structural sys-tem. In the early stages of the design the floor plan sketches do not yet have these typical characteristics. In such cases, simple coloured areas may be used to indicate sequences of spaces that will eventually provide the configuration of the building. Floor plans of this type are gen-erally at a scale of 1:200. In the later planning stages floor plans must be drawn at scales of up to 1:50.
Sketch section at the design stage with depiction of the surroundings
The section is made by placing a vertical section plane in the design on which everything that you see when looking in a specific horizontal direction is then depicted. The section plane should be chosen in such a way that all the important room heights, the way the structure works and the circulation of the building can be read. What lies close to the section plane is drawn clearly; building parts that are further away can be drawn more lightly in elevation.
Sectional drawing made at the design stage showing surrounding buildings and trees
During the early design phases the sketched section is a most important means of illustration. Often it is needed in order to clarify decisive spatial situations. The scale of building sections and elevations depends on how far the design of the floor plans has advanced. If the floor plans are drawn at a scale of 1:100 it makes sense to draw the sec-tions and elevations at this scale too. Urban planning sections through terrain are generally drawn at a scale of 1:500. To grasp the complexity of Learn more...
a building a number of sections are gen-erally needed (at least one cross section and one longitudinal section). As with the floor plan the walls and ceiling slabs cut through are coloured dark or crosshatched, and important edges that are not directly visible are indicated by dashed or dotted lines. The position of the top of the sur-rounding terrain should be shown in every section and is depicted by a strong line. If the design involves changing this level the original edge of the terrain can be shown as a dashed line. Elements that provide a sense of scale, such as people, vehicles and vegetation, give section and ele-vation drawings a certain lively quality and make them easier to read.
The elevation (or view) is a planar drawing that shows one external face of a building. It could be regarded as a sectional drawing in which, however, the section plane is not inside the building but outside and directly in front of it. The elevation depicts the proportions of a design or reveals the relationship of the planned building to its surroundings (neigh-bouring buildings, nature etc.). The relief of a building (facade, windows, projections) should also be visible and can be shown by means of shad-ows. This gives an essentially planar drawing such an elevation a certain depth. Building parts in the background are, as in the section, drawn more faintly and with separated lines.
Elevations of one design at different scales in a sketch
Elevation developed from sketched floor plans
During architectural design the elevation can be sketched directly beside, above, or below a plan drawing, as the lengths required are already given. It is important that the ground line on which the building stands be emphasized, and that the planned building be clearly distinguished in the drawing from the neighboring buildings.
If you wish to define the construction or materials of a building precisely, you must proceed to drawing at a smaller scale. What are called the details of the building are shown in section, elevation or perspective drawings. Particularly important are detail sketches of those places where the different parts of the building are pieced together, where materials meet, where construction meets design. The term “detail drawing” can cover drawings made at very different scales. A very detailed depiction at the scale of 1:1 to 1:5 is clearly a detail, but so is the depiction of a facade at the scale of 1:50, as this offers far more detailed information than the scale normally used for an elevation drawing.
Large-scale staircase detail with indication of colours and materials
In detail sketches it may be necessary to define certain materials precisely. There are standards that lay down the kind of hatching or lines used to depict materials. In a large scale section the cut building parts are indicated by thicker lines. To allow visual checks to be made frequently, a part of the relevant internal and external elevation and a floor plan are drawn alongside the detail section drawing (vertical or horizontal section).
Small-scale development of details using different types of drawing
Axonometric projections combine the advantages of planar and three-dimensional drawings as they combine both kinds of depictions: in some kinds of axonometric projections, the depths and heights of rooms can be measured from the drawing. These drawings are frequently used in the architect’s daily life to depict simple spatial relationships. They are often based on existing drawings and in such cases adopt the scales of these drawings. The three simplest and most common axonometric projections used in architectural design are the floor plan axonometric, the elevation axonometric, and the isometric projection.
Floor plan axonometric, elevation axonometric and isometric projection.
The floor plan axonometric as an exploded drawing (which can also be made on the basis of an isometric) is very informative but relatively time-consuming. Here, the different floors, building parts or planes of the construction are shown separated from each other but linked by connecting lines and by the geometric severity of the axonometric projection.
The elevation axonometric projection (also sometimes called cavalier projection) is based on the elevation. The elevation of the building is viewed frontally; the volume develops behind it at an angle. The depth of the building volume is shortened, generally by a third or a half. This form of axonometric projection is easy to produce if an elevation of the design is already available.
Floor plan axonometric projection as an-exploded drawing.
Rapidly sketched isometric to explain a spatial situation, with elevation
The isometric (“iso” comes from the ancient Greek and means equal) offer true lengths in all directions, however the floor plan is distorted and shown without a right angle. Therefore the isometric cannot be made on the basis of an existing drawing.
Continuing the design But the additional effort involved in making this kind of drawing is worthwhile, as the isometric has the illustrative character of a bird’s eye view. The isometric is often used in drawing overview plans.
A perspective drawing differs in one important point from the floor plan, elevation, section and axonometric: it has one or more vanishing points. That is to say parallel edges, building parts or buildings are not drawn parallel to each other but meet at a vanishing point. Perspectives are particularly suitable for making a building understandable in a clear, communicative way that lay people can grasp. Such perspectives are of-ten drawn from the eye level of someone passing by a building, as the aim is to depict spatial impressions realistically. In addition to the outer spatial configuration, the perspective also shows particularly clearly the form and proportions of a building and how it is integrated in urban design.
Rapidly drawn perspective (not constructed) at the height of a passer-by for an urban design ideas com-petition
In the perspective that a lay person can easily read, the horizon, which in such rapidly made perspectives is generally not drawn, usually lies in the area of the ground floor of the building. This creates the illu-sion of a realistic passer-by’s view of a building in its spatial setting, whether this is the city or the country.
Bird’s eye perspectives are three-dimensional drawings looking down from the sky, i.e. the station point of the perspective is above the 56 building. Like the site plan they show both the building and its surround-ings. You see a distorted top view of the building itself and at least one elevation.
The combination of section and perspective known as the sectional perspective is a most communicative form of depiction. It can show the architectural characteristics known from the section, while giving the drawing a spatial dimension.
The perspectivised elevation suggests, in perspective, an area in front of a building, and in this way counteracts the absence of perspective in a classic elevation. As long as the elevation does not suffer in graphical terms, it can improve the otherwise rather abstract elevation of a building.
Sectional perspectives of sports halls
To construct a perspective in this way you require a floor plan and at least one elevation of the design. These drawings must be put on the paper, at the same scale, before the perspective is constructed – in the form of a sketch, copy or print. Ideally, however, the perspective should be drawn on transparent paper; the drawings referred to above can be placed beneath the transparent sheet.
Schematic construction of a perspective (the perspective will be drawn in the crosshatched area)
Preparation and construction of the vanishing points
Transfer of the true height and construction of the perspective
On the sheet the perspective is constructed from bottom to top. Near the bottom edge of the sheet is the station point (SP). Now the floor plan must be positioned in such a way that the desired perspective can be drawn. The distance to the station point must be determined, and the floor plan must be swivelled until an interesting view is found. The eleva-tion is placed above the floor plan, not centrally but to the left or right of the floor plan. The perspective is created alongside the elevation and above the floor plan. The picture plane (PP) is drawn through the floor plan as a horizontal line, parallel to the ground line of the elevation. Its position determines the size of the final perspective. Ideally it should be positioned so that it cuts at least one important corner or edge of the building. In the elevation drawing the vertical position of the horizon (HO) is chosen. It is drawn parallel to the ground line of the elevation and to the picture plane in the upper part of the sheet.
Changing the position of the picture plane, the horizon and the station point and swivelling the building
This preparatory work should be carried out before constructing the perspective. Now the vanishing points needed are constructed. To do this lines are drawn parallel to the orthogonal outside edges of the floor plan and are extended to meet the picture plane. At each of the points where they meet this plane a vertical line is drawn up to the horizon. These two new points are the two vanishing points.
Note: Although this construction method is relatively time consuming it produces only a small perspective. It also requires a good understanding of the procedure and the variables. Only the main principles are presented in this book. Construction methods employing one or three vanishing points are not dealt with, nor are the construction of shadows or perspectives of non-orthogonal floor plans.
Perspective based on the point projection construction method
Now the perspective can be created step by step. From the first edge of the building vanishing lines are drawn to the next building edge, the position of which has been defined by the verticals already drawn. Seen from the eye-point the right-hand sides of the building sides always van-ish to the right vanishing point and left-hand sides to the left vanishing point.
In this method, four variables determine the appearance of the con-structed perspective. If you change the position of the picture plane in relation to the floor plan this changes the size of the drawing. Only those building parts on the picture plane retain their size. The horizon deter-mines the vertical height of the station point. If the elevation drawing cuts the horizon you obtain a view of the building from above or below. Shift-ing the station point immediately changes the perspective. If it is close to (far from) the floor plan the perspective can seem very dramatic (flat). If the floor plan is turned until it reaches the desired position in relation to the station point, this changes the position of the vanishing points.