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RE: Mechanical Engineer wants me to stamp his M sheets

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Gerard Madden wrote:

 

“ Just finished a big project for DSA (a division of DGS) who had the architect sign and seal all 447 sheets of the drawings set, including the 35 structural sheets. “

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It makes sense. The architect as principle designer is responsible for delegation of work to specialist consultants. If they wanted to they could design everything themselves. But it would be beneficial to get certain aspects of the design reviewed by specialists. Evaluating fitness-for-function against mandated performance criteria is not the same as design, nor is documentation and presentation the same as design. If I want to design a structure using 2kPa wind load I can, and the resultant specification will in most instances be found code compliant because the code will produce a pressure of around 1kPa or less. There are also other issues to consider in design, such as economy of fabrication and construction: there are a multitude of other issues where the minimum size for a member is larger than that recommended by purely structural considerations. So design first, code checking last.

 

The architect as principle designer is responsible for bringing all those other issues together and deciding on the final specification. By sealing all the documents the architect is declaring everything has been coordinated, all issues have been considered, and the whole building is fit-for-function. They are also declaring a confidence in the SE they appointed for the structural design. If the architect refuses to sign the structural drawings, then they must have issues with the competence of the SE they appointed, in which case another SE needs to be appointed to review the proposal. The architect should have the competence to read the SE’s drawings and accept or reject as suitable for their project. The architect’s prior experience should alert them as to whether the current SE is under or over sizing: leading to a requirement for the SE to justify or be replaced.

 

Personally I don’t see why the architect cannot document the entire project, it would be far more efficient, and they would have done so historically. The engineers and other sub-consultants are employed to provide design input, and specialist skills in evaluating sufficiency-of-purpose. Drafters produce the formal documents, and can produce about 80% of the content without engineering or architectural input. Designers may present their ideas as technical drawings but it is the drafter who turns it into a controlled document. So the architect could employ all drafters in their office, and doing so would re-integrate a lot of the design content into the mind of a single design-drafter. Especially more efficient when using layers and external references in CAD, or the more hi-tech BIM packages. The drawings are simply a virtual model built on paper, and the engineers and other designers simply supervise its construction on paper. The division between specialists is relatively artificial and arbitrary: specializations increase by the year. So having the principle designer in control of all documentation and presentation standards has its benefits.

 

For that matter separate the documentation process from the designer’s altogether. Traditionally technical drawings were produced to solve problems: now drawings seem only to exist as a means of presenting solutions. With documentation becoming an end within itself: rather than a means to an end. So architects and engineers can both get their documents produced by an independent drafting service. Forcing the designers to reconsider the value of drawing as a problem solving tool, and that they themselves should still be working at a drawing board (or CAD). Also to further recognize the real value of their services, given that many projects are simply documentation exercises, in need of technical review. And also noting that past documentation potentially presents design content more robust than what modern incomplete codes of practice permit. That is if do not have experience of past practice, then design purely to the code will most likely produce something defective: because there are a multitude of design issues not covered by the codes. So a drafter with 30 years experience may produce a better solution than a code-cruncher.

 

So what really matters is that a design proposal is properly documented, and that such documented proposal has gone through an adequate series of checks to ensure that the proposal is fit-for-function, sufficient-for-purpose and ultimately code-compliant. The code issues coming last. Further that there is a principle designer to address issues not properly addressed with respect to fabrication and construction, and to properly coordinate and re-evaluate design changes arising from the need to make the implementation of the proposal feasible and practical. For a building that person is usually the architect.

 

Regards

Conrad Harrison

B.Tech (mfg & mech), MIIE, gradTIEAust

mailto:sch.tectonic(--nospam--at)bigpond.com

Adelaide

South Australia