Should the Designer Consider the Construction Process 2

[DRC1]

AggieYank asked in "Contractor Calls About Construction Loading" what responsibility does the Structural engineer have to check the suitibilty of the structure for the contractors equipment. The subsequent discussion has brought me to ask the following question: How much should the engineer consider the construction practice in his design, and what should he communicate to the contractors about the construction loads and sequence to the bidders and contractors.
My take is that although the designer can not consider exactly how the structure will be built, some consideration of the construction process and communication of those thoughts will go a long way in achieving more constructable projects that will go more smoothly and more profitably for everyone. What does everyone else think?

 

[HvZ]

This a very important issue. If it is not going to be constructed the way it is designed and detailed, because it can not be constructed the way it was detailed or the contractor wants to do build it differently, then the design is no longer valid.

The easiest project arrangement is an alliance or D&C project where the contractor and designers are in together from the start. discussing and understanding the intended method of contruction at the start saves a lot of time evaluating and reworking designs to suit construction.

In a conventional tender contract, where the design is finished by the time contractor gets appointed, it is vital to have and experienced designer and/or reviewer who know what can and cant be constructed.
In this situation, I always meet the contractor before the start of the contract to go through the design intent and the method of construction.

Just on another subject, I have on numerous occasions come across designers that instead of taking the time to develope a specific detail, they say "they can sort it out on site". Just remember, if you can not draw it, the contractor can not build it.

Cheers

HvZ

 

[archeng59]

design for constructability. mass production of as many components as possible. think about sequencing of erection. how would you build your design if you had to build it? are there beams that must be temporarily supported by a crane or temporary shoring until another set of beams are installed? can you eliminate any of that by redesigning the framing? on buildings where the architect has brick veneer above a roof level, I sometimes (more often than not) design the framing to support mason's scaffolding to eliminate temporary shoring under the framing. this was a recommendation by a contractor on a job I designed early in my career: eliminating the temporary shoring allows other trades to work inside the building while the brick is being erected. I always ask friendly contractors about the building they are constructing to see if there is any recommendations for making their job easier. sometimes they offer stuff, sometimes not. sometimes a happy contractor can be a source of work thru recommendations.

 

[yogia]

Interesting thread about structural engineer's concern about constructibility ... I agree that the structural engineer should be clear about the construction plan for the project.

This was quite some time ago, and I know that now I am digressing, that we used to talk about the demolition plan as well at the design stage.

And of course as has been alluded to by some already, the legal issues, the insurance issues, the accountability issues, the liability issues, ... have been a big facor lately on what and how we do, are willing to put on paper, and willing to document.

Yogi Anand, D.Eng, P.E.
Energy Efficient Building Network LLC
ANAND Enterprises LLC

http://www.energyefficientbuild.com