New dimensions in construction planning

Before a building is erected, the first thing to do is to create a construction plan. It consists of a floor plan and a sectional drawing of the planned property. As precise work templates, they ensure that every detail is precisely planned and executed. These large-format technical drawings retain their relevance, even after the house has long been up, for example when it is to be converted or sold.

Some changes to the owner or the terms of use of a property require changes to a building. For this, it may be necessary that the planned change is added to the existing sectional drawing. But not in every case you have to hire an architect. A building owner can often save these costs by changing the sectional drawing himself with the right software.

Floor plan or sectional drawing?

When talking about a construction plan, as a layperson, one thinks first of a drawn floor plan. A sectional drawing – and what exactly you have to imagine it to be – is mostly unknown. Here are two brief definitions of the two terms. They explain what the difference is.

The floor plan

A floor plan gives the viewer a view from above of the individual levels of a building. The floor plan shows the course of the outer walls, the shape and division of the interior spaces as well as the placement of windows and doors. The precise details of the room sizes make it possible to plan the creation and use of all building areas to scale. The respective wall thicknesses are also given. They are drawn in as one-dimensional surfaces, the dimensions of which can be determined precisely.

The sectional drawing

Different terms are used for a sectional drawing by architects and in construction. It is also called a crack drawing, or crack for short, because it represents a cross or longitudinal section of a building. Often there is also talk of a sectional view or, in short, a cut. It always shows a sectional plane of the building, which can run both lengthways and crossways. With sectional drawings, structures in the building that are hidden in the finished object are visible. All contours that lie under the surface of the building are drawn in.

The areas of application for such elevation representations are very diverse. It may be necessary to make several sectional drawings to illustrate the interaction of different components. They are also used as technical drawings and depict structural specifications for the architecture from different perspectives.

What does a sectional drawing represent?

The entire building can always be seen on a sectional drawing. The cut runs right through its center so that all levels are covered. It is thus possible to visually display all important information and to provide it with dimensions. For example, whether a building is on level ground or on a slope. The height of the room in the individual floors and the type of ceiling mounting can also be seen from the sectional drawing. In short: the sectional drawing provides information that cannot be seen from the floor plan.

Official requirements

In order to apply for a building permit, both documents must always be available to the local building authority: a floor plan and a sectional drawing of the planned building. If only a floor plan is available, no building authority will examine a project. No building application will be processed without a sectional drawing. This applies to both a new building project and a planned renovation.

Little importance in sales

In contrast to the official building authority, the sectional drawing hardly plays a role when a building is sold. It is of little importance for prospective buyers. At best, it can provide a decisive argument in favor of buying the property.
Even if the house is offered for sale through a realtor, the sectional view is of secondary importance. Prospective buyers are usually only interested in seeing the floor plan in order to get an idea of ​​the furnishing options the property offers them. In order to give a visual impression of the architectural style and the atmosphere in the interiors, photos taken as professionally as possible are better suited.

How do you read a sectional drawing correctly?

A sectional drawing shows how a house is constructed. The architectural sign language conveys all important information about its external and internal structure. You can see how the rooms are integrated, where the fireplace runs and where the stairwells and load-bearing elements are.

Depending on what is to be shown, a longitudinal or a cross-section is made. A dash-dot line indicates the course of the cut. A continuous line can be seen where it cuts through walls. The sectional drawing shows what lies behind the cutting line. In order to be able to read the drawing correctly, an observer must know from which perspective and on which scale the drawing is made. This information can be found along with other technical details in the title block of the sectional drawing.

Can also be used off-road

Sectional drawings are not only available for buildings. This technique is often used to display the condition of the subsoil. This is particularly advantageous if the construction site is uneven or if the building is to be on a slope. A terrain sectional drawing provides important information about the foundations that should give the house a firm footing. They are indispensable for construction planning right from the start. The decision as to which devices should be used in the individual construction phases is based primarily on them.

Three-dimensional representation

The use of modern 3D technology has proven itself when setting up existing buildings. This procedure, which experts call orthogonal axonometry, is known under the term “exploded view”. The method comes from military technology and it can represent a terrain in its real orientation. This creates an exact basis for technically difficult constructions. By rotating the floor plan by 45 degrees, a spatial effect is created that vividly shows the relevant conditions. The required data can be read off in the section and in the corresponding text field.

Precision work according to exposure drawings

Gone are the days when sectional drawings were only two-dimensional. With the help of modern computer technology, it is possible to generate perspective representations with which the structural connections in a building become vividly visible. As with an explosion, individual elements of a drawing are shown offset. This makes construction-related relationships visible that a drawing in 2D format could not show. These exposure drawings are a valuable template, especially for the complex course of power lines or pipelines, which require fits that are accurate to the millimeter. Because even the smallest deviations are enough to cause costly damage.

Ingenious software replaces expensive experts

The planning of floor plans and the creation of sectional drawings still belong in the hands of experienced specialists. It is not for nothing that architects, civil engineers and technical draftsmen complete a long period of study or training in order to be able to cope with the responsibility that the construction of a building or a technical system entails. For this reason, their work also comes at a high price, which is well justified in any demanding new building.

But not every homeowner has the money to hire an architect if he is planning to build a porch or a carport. Therefore, software providers now offer solutions with which at least smaller projects can also be planned by laypeople. With their intelligent tools, it is possible to make certain sectional drawings yourself. The quality of most software solutions is excellent, which has meanwhile been checked and confirmed by competent tests.
The quality standard of these software solutions today corresponds to the high demands that building authorities place on them. Therefore, the chances are good that an underdeveloped building owner will also receive an official building permit with a sectional drawing that he created himself with this software.