Types of Drawings | Engineering

1. What Is Working Drawing?
In engineering working drawings are reference drawings made according to the
design to be used in site by the contractor. Working drawings are two types, the
detailed drawings and the assembly drawings. Detailed working drawings, must be
able to present more information of a particular component that is proposed to be
constructed, and may have several views of that component. While an assembly
drawing shows details of how pieces of a given body fits together. It has the different
pieces drawn separately and how they fit to finally have whole body together. Both of
these types must be drawn to scale and have correct measurements.
The engineer, whether civil, electrical, or mechanical, prepares his/her designs, and
sometimes he draws them as well, but more often send them to the draughtsman to
prepare the drawings on a machine. Most draughtsmen use AutoCAD or Revit to
implement the designed drawings. After the drawings have been prepared by the
draughtsman, they are then taken to site and handed to the contractor who shall
implement them on the ground.
2. Construction Drawings
Generally, drawings are essential part of any engineering work. They form part of the
information relayed about what is proposed for construction. This is what is called
construction drawings. They are a part of the information relayed for tender opening
during construction, giving the contractor more information about what is to be
constructed and other parameters that are essential for the construction. Construction
drawings in building and construction, are like:
Architectural drawings – which incorporates the general view of a building (plan,
elevations, cross-sections, and isometric views) and other details of that building, like
internal elevations.
Structural drawings – these shows the structure and support mechanism of the
building, like the reinforcement bars (for the slab, beams, staircase and columns),
foundation layout, roof layout (plan and truss sections), top floor slab etc.
Mechanical – these are drawings that shows the plumbing of the site, air conditioning
plan, and other details related to mechanical works.
Electrical – these are drawings that shows the plan of artificial lighting, power points,
schematic diagrams for electrical, etc.
3. Specifications (specs)
Specifications come from the word “Specific” or “particular” in English to mean a
given item singly. Specifications in engineering are a set of documents giving details
about the requirements on site that satisfies the materials that are to be used on site.
The document must describe particular materials in details, meaning their form,
structure, manufacturer, texture, and so on. These material details must have been
incorporated in the drawings that were presented by the engineer. The material
specification must also adhere to the technical standards. In other field of engineering,
manufacturing for instance, specifications describe the details of the features or the
contents required for the design of a given product. Once the product has been
manufactured, a manual is produced which dictates how the product can be
assembled, used and the conditions of use. Some manufacturers produce data sheet,
also known as the specification sheet, this shows the technical specifications and

features of a product. This is usually to help a customer choose what fits them at a
particular time.