What is Steel Detailing

Training and Certification
Responsibilities
Techniques

STEEL DETAILING IS A SPECIALIST AREA OF STRUCTURAL DRAFTING
A Steel Detailer interprets architectural and structural engineering drawings to gain a thorough working knowledge the overall design intent of a building or structure. Using this translated information he then produces an altogether different set of clear, unequivocal and accurate drawings for the purpose of steelwork fabrication.

To highlight the difference between design and detailing;

Design is the creative process of taking an idea from conception and putting that concept to paper for the purpose of manufacture where Detailing is the first practical step of steel fabrication and as such is critical to the construction program.

Steel detailers (usually simply called detailers within their field) work closely with architects  , engineers, builders and steel fabricators. They usually find employment with steel fabricators, engineering firms, or independent steel detailing companies. Steel detailing companies and self-employed detailers subcontract primarily to steel fabricators and sometimes to builders and design consultants.

The engineer should provide arrangements (plans, sections & elevations) that show all of the structural elements required. This is usually done in skeletal fashion (stick diagram) with steel members being represented by a single line. All of these elements must be given a member size, orientation and design of their respective end connections.

The architect's drawings should flesh-out the engineer's skeleton, by providing all necessary construction details, dimensions, levels and steelwork locations.

Please refer to the AISD Design Document Completion Checklists for more information on this topic.

Training and certification
Tertiary Qualifications specific to structural steel detailing do not currently exist in Australia and are in fact rare anywhere in the world. More general degree and certification programs may be found with curricula pertaining to design, manual or computer-aided drafting in general, or specific computer-aided drafting software. A qualification is not required to become a steel detailer in Australia. Training is usually provided on the job, with a new trainee usually needing about four years of practice under an experienced detailer to become proficient with all of the requirements of the trade. Practitioners of this occupation may range from degreed, and possibly licensed, civil/structural engineers to those with little or no formal academic training who nevertheless possess extensive industry experience

The AISD is currently developing a nationally recognised qualification for Steel Detailers to Diploma level. It's hoped delivery of this tertiary program will begin in the 2010 academic year.

Responsibilities
All steel members required to build the structure are fabricated and erected from shop and erection drawings created by the structural steel detailer.

The steel detailer prepares his drawings based on information presented on design drawings of a structural engineer (structural design drawings) and/or architect (architectural design drawings). The design drawings may also include information related to mechanical systems which is relevant to the fabrication of structural members, and which must necessarily be incorporated by the steel detailer. In the case of buildings, this information is typically related to HVAC design, but in the case of industrial projects may generally include information relating to the ultimate industrial purpose, such as pumps, piping, material handling equipment, and other types of industrial machinery and equipment. The total package of design drawings contains information relevant to all trades, and the detailer must coordinate and extract the information required to generate detailed shop drawings usable by the steel fabricator. The design drawings show information in a general way, such as material sizes and connection requirements, and it is the detailer's responsibility to translate these general requirements (the “design intent”) into detailed drawings for each specific steel member in the structure. In this way the detailer acts as an interpreter of the design drawings for the fabricator.

A steel detailer prepares two primary types of drawings: erection drawings and shop drawings.     

  • Erection drawings are used to guide the steel erector on the construction site as to where and how to erect the fabricated steel members. These drawings usually show dimensioned plans to locate the steel members, and they often also show details with specific information and requirements, including all work that must be done on site (such as bolting, welding or installing masonry anchors). Since the erection drawings are intended for use in the field, they contain very little specific information about the fabrication of any individual steel member; members should already be completed by the time the erection drawings are used.  
  • Shop drawings, also called detail drawings, are used to specify the exact requirements for fabricating each individual member (or assembly) of a structure, and are used by the steel fabricator to fabricate these members. Complete shop drawings show material specifications, member sizes, all required dimensions, welding, bolting, surface preparation and painting requirements, and any other information required to describe each completed member. The shop drawings are intended for use by the fabrication shop, and thus contain little or no information about the erection and installation of the steel members they depict; this information belongs in the erection drawings. 

The detailer must comply with the requirements of the design drawings and with all industry standards and protocols, such as those established by the Australian Steel Institute (ASI) and the Australian Institute of Steel Detailing (AISD). The detailer is not usually responsible for design, including structural strength and integrity (which are the responsibility of the structural engineer), major dimensions of the structure and compliance with relevant building codes (which are the responsibility of the architect). A detailer is generally required to submit his drawings to the structural engineer and/or architect for approval prior to the release of drawings for fabrication. In the case of non-building projects there is typically no architect, and detail drawings are reviewed exclusively by the structural engineer. This design review ideally assures engineering accuracy and compliance with the design intent.

Techniques
Traditionally, steel detailing was accomplished via manual drafting methods, using pencils, paper, and drafting tools such as a parallel bar or drafting machine, triangles, templates of circles and other useful shapes, and mathematical tables, such as tables of logarithms and other useful calculational aids. Eventually, hand held calculators were incorporated into the traditional practice. 

Today, manual drafting has been largely replaced by computer-aided drafting (CAD). A steel detailer using computer-aided methods creates his drawings on a computer, using software specifically designed for the purpose, and printing out his drawings on paper only when they are complete. Many detailers would add another classification for those using 3-D Modeling applications specifically designed for steel detailing, as the process for the production of drawings using these applications is markedly different from a 2-D drafting approach.

Structural steel detailing requires skills in drafting, mathematics (including geometry and trigonometry), logic, reasoning, spatial visualization, and communication. A basic knowledge of general engineering principles and the methods of structural and miscellaneous steel fabrication, however acquired, is essential to the practice of this discipline. A computer-aided detailer also requires skills in using computers and an understanding of the specific CAD software he is to use.

A detailer's drawings generally go through several phases. Following creation of the drawing, the detailer must usually (as described above) submit a copy of the drawing to the architect and engineer for review (“approval”) Copies of the drawing may be sent to other recipients at this time as well, such as the builder, for informational purposes only. The drawing must also be checked for accuracy and completeness by another detailer (for this purpose, the “checker” Comments arising from approval and corrections made during checking must be resolved, and the original drawing must be updated accordingly (or “scrubbed”). After this, the drawing may be released to the fabricator and/or erector for use in construction.