Design-Build & Design Build Methods 1

[desnov74]

Hello all,
I met a fellow engineer on the commute who really had a lot to say about design methods that were performance based.(sounded more like a blend of performance and prescriptive but anyway..) He claimed he could really get the cost down by competitive bidding to meet his specifications. Then spends more time reviewing shop drawings, simulating a lot more, and checking calculations thoroughly for feasibility. He claims he can control quality and lower the price. He went on to say that the design method would be perfect business model for a design-build engineering firm he wants to start, because he can control costs and ensure quality.
What does everyone think of this business plan?

 

[DonPhillips]

Why not just say the code is the minimum and review the designs against that specification? Cannot get any cheaper than that, and you can create minimum standards above code to meet the client's needs.

I am not sure what he is describing is a business model unless he is "design-builder", and subbing it out for less than his bid, and making money off the subs - like a contractor.

Don Phillips

http://worthingtonengineering.com

 

[desnov74]

DonPhillips,

I think that is his point, to operate like a general and sub-out the actual work. I think the idea of the minimum above the code, he would want to leave open in order to allow for possibly allowing for alternatives to prescriptive requirements.

I guess my question is how do performance codes work, in terms of affecting the AHJ, owner, and contract documents? Then how does that affect things like E&O insurance, liability, pricing, etc?

 

[DonPhillips]

The IBC is mostly a performance code. I guess I am not sure what your question is.

You have a duty to meet the minimum requires of the code, which the AHJ enforces through plan review and inspections.

You have a duty to try to meet your client's needs, so you create the project documents to do that.

Perhaps the drawings are not detailed, mostly schematic or conceptual, and require details through shop drawings to verify it meets the contract requirements. This is pretty typical for storefronts, trusses, sprinklers, and fire alarm systems. Sometimes HVAC systems, where the main trunk and runouts are sized, the air-handlers and coils are sized, but the specific equipment must be submitted for approval. Lighting would be generalized with no specific design.

I guess when it comes to electrical, since the NEC is a pretty prescritive code (except portions allowing engineering supervision), the only creative portion would be sizing and routing of conduit to minimize costs.

Looking at the lighting example, if I am reviewing a set of documents that say provide a lighting design for 50 fc at desktop (and code requires 10 fc at floor level for occupiable spaces), I would issued a partial approval and require the lighting design be submitted for approval. In addition to the minimum of 10 fc, the code limits the amount of lighting as well so the design must be completed and submitted for approval.

Perhaps that is an example of the AHJ and Owner question.

I am not sure how E&O is affected except you are spreading design risk out but taking on construction risk. My carrier ensures that I understand I do not do construction management. Liability for design is similarly spread out but now you pick up construction risk.

Pricing - you have to be willing to eat some construction costs for your mistakes so you need to make sure you cover that in your price.



Don Phillips

http://worthingtonengineering.com

 

[lansford]

In my geographic area, the businesses (owner) would much rather do things over several times than to "pay" for engineering.
Some of the contractors in the area are just too eager to give someone a buid in their "design build" job.
JIM

 

[DonPhillips]

Same in my area - I am sure it is very common everywhere. I know one who hired an architect, went through zoning, and submitted those zoning drawings for a permit (350 sf addition to an existing 2000 sf repair garage) and it took me more time writing up the correction letter than it would if he did not jump the gun and submitted the full set of drawings. I am not sure what people are thinking.


Don Phillips

http://worthingtonengineering.com