(Can we/ should we/ do we need to) require EOR signoff on shop drawings.

[WoodDesignCat]

I work for a company that prefabricates structural wall panels (all the walls in building, shear walls, load-bearing walls, non-load-bearing walls). I think that the EOR should be reviewing our shop drawings to ensure that our panels will match their design intent, but on a few jobs the engineer has not required the review of our drawings and the contractor has been the sole entity "reviewing" our shop drawings and signing off on them.

Is it really up to the engineer on whether or not they require engineering review, or should we, the manufacturer, be requiring an engineer's signoff? Everything that I've read basically says it's up to the engineer and contractor, and if the engineer doesn't require their own review, the contractor can take full liability and sign off themselves if they choose to. It doesn't seem like it should work this way to me. If this is really how it works can we even require sign-off from the engineer and architect?

I should clarify that we just pre-cut panel splices, window, door, electrical, and plumbing holes. All connections between panels and other framing are made onsite. We do not currently make different strength panels, the strength is determined by the onsite connections. However I think the placement of electrical/plumbing holes, and the placement of panel splices would be worth review by the engineer.

 

[JAE]

Depends on the jurisdiction you are in but the options as I see them are:

Option 1 - Delegated Design
The EOR requires on the drawings that all wall panels will be designed per loads and parameters given on the plans.
The manufacturer then is required to have a licensed engineer in that jurisdiction design the panels and submit signed/sealed drawings to the EOR for review.
The EOR then is still responsible for the overall structural system of the entire building (they can delegate design tasks but can't delegate ultimate responsibility).
The EOR should review the submitted plans for general conformance with the contract documents as well as verify that a licensed engineer has stamped them.
The EOR may and probably should, review some of the calculations by the delegated engineer.
The EOR does not have to stamp and sign the submitted documents - in fact in most US states they can't as they didn't perform the design under their direct supervision.

Option 2 - Dictated Design - Minimal Changes
The EOR performs the design of the walls - i.e. specifying the studs, spacing, etc. or the actual nature of the wall designs if not wood.
The EOR, on the plans, may state that they would allow a pre-manufactured system of walls.
The EOR then would state what submittal requirements are needed.
If the nature of the pre-manufacturing requires some additional structural design, then a licensed engineer might be required for that portion of the altered design.
The EOR should review the submitted plans for general conformance with the contract documents.
The EOR may and probably should, review some of the calculations by the licensed engineer.
As before, the EOR does not have to stamp and sign the submitted documents.

Option 3 - Dictated design - Significant Changes
The EOR performs the design of the walls - i.e. specifying the studs, spacing, etc. or the actual nature of the wall designs if not wood.
The EOR, on the plans, may state that they would allow a pre-manufactured system of walls.
The EOR then would state what submittal requirements are needed.
If the manufacturer wants to use something different than what the EOR designed directly, then a licensed engineer would be required to show and verify that the altered design is OK.
The EOR should review the submitted plans for general conformance with the contract documents.
The EOR may and probably should, review some of the calculations by the licensed engineer.
As before, the EOR does not have to stamp and sign the submitted documents.



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[WoodDesignCat]

Thank you for the response JAE. "Option 2 - Dictated Design - Minimal Changes" is what we try to do. I added notes to your steps below to give you a better idea of what we do. My main question is on third to last and the last point

Option 2 - Dictated Design - Minimal Changes
The EOR performs the design of the walls - i.e. specifying the studs, spacing, etc. or the actual nature of the wall designs if not wood. Yes, but it's solid panels no studs. But what if the engineer doesn't give explicit instructions on something and we manufacture it assuming it isn't structurally significant, but it really is?
The EOR, on the plans, may state that they would allow a pre-manufactured system of walls.I don't think they have stated this, but our product is only available as pre-manufactured
The EOR then would state what submittal requirements are needed.What if the engineer does not state any extra submittal requirement?
If the nature of the pre-manufacturing requires some additional structural design, then a licensed engineer might be required for that portion of the altered design. We have not been required to have a licensed engineer sign off on our shop drawings. However, it could be argued that the placement of our panel laps could affect structural design.
The EOR should review the submitted plans for general conformance with the contract documents. What if the engineer doesn't ask for this and the contractor is the only one reviewing the plans?
The EOR may and probably should, review some of the calculations by the licensed engineer. We leave the design phase entirely up to the EOR
As before, the EOR does not have to stamp and sign the submitted documents.Is this really true? If an engineer doesn't want to review shop drawing they can leave it entirely up to the contractor? The contractor can be in charge of saying that shop drawings comply with the architect's and engineer's intent? A contractor doesn't fully know an engineer's intent, but the engineer doesn't have to review shop drawings?

 

[structSU10]

The last point in JAE's comment about stamping and signing isn't about review - its about taking responsibility for the design. If there is some form of structural importance to the component, and it was specified on the structural contract documents, the structural EOR should review it.

You said the design is up to the EOR - what kind of panels are these? how is the EOR spec written? Most facade systems have become a delegated design, with the engineer providing loading criteria, and having the manufacturer hire an engineer to do it - that is not what you get into? Most of the time the EOR has no idea what manufacturer is ultimately going to be used, so can't truly design some of these systems - especially the connections. In those cases, an delegate engineer should be involved to define all of those requirements for the selected system. The EOR, in that case, checks for general conformance, but again would only 'stamp' the drawings that they reviewed it. They should make sure the delegate engineer understood their intent, and the manufacturer understood the layout intent as well.

 

[JAE]

My responses in Green:

Option 2 - Dictated Design - Minimal Changes
The EOR performs the design of the walls - i.e. specifying the studs, spacing, etc. or the actual nature of the wall designs if not wood. [red]Yes, but it's solid panels no studs. But what if the engineer doesn't give explicit instructions on something and we manufacture it assuming it isn't structurally significant, but it really is?[/red][green] Whether solid panels vs. studs probably doesn't matter here. If the EOR does not provide much of any guidance - then it is more of a delegated design - not a dictated design. You have to have something defined to dictate it. We do a lot of precast concrete design off EOR drawings that sometimes are terrible...we send back requests for information (sometimes dozens) to get the info we need for design [/green]

The EOR, on the plans, may state that they would allow a pre-manufactured system of walls.[red]I don't think they have stated this, but our product is only available as pre-manufactured
The EOR then would state what submittal requirements are needed.[red]What if the engineer does not state any extra submittal requirement?[/red][green] OK - [/green]

If the nature of the pre-manufacturing requires some additional structural design, then a licensed engineer might be required for that portion of the altered design. [red]We have not been required to have a licensed engineer sign off on our shop drawings. However, it could be argued that the placement of our panel laps could affect structural design.[/red][green] Send the EOR and RFI to ask about it. Also - depending on where the project is, the local engineering laws could require you to have a licensed engineer design and sign your work regardless of what the contract documents say.[/green]

The EOR should review the submitted plans for general conformance with the contract documents. [red]What if the engineer doesn't ask for this and the contractor is the only one reviewing the plans?[/red][green] I might be inclined to send your work in anyway - puts the responsibility for overall structural responsibility and review on the person on whom it belongs...the EOR [/green]

The EOR may and probably should, review some of the calculations by the licensed engineer. [red]We leave the design phase entirely up to the EOR[/red][green] If I was the EOR I'd want to see some of the design assumptions at the least.[/green]

As before, the EOR does not have to stamp and sign the submitted documents.[red]Is this really true? If an engineer doesn't want to review shop drawing they can leave it entirely up to the contractor? The contractor can be in charge of saying that shop drawings comply with the architect's and engineer's intent? A contractor doesn't fully know an engineer's intent, but the engineer doesn't have to review shop drawings?[/red][green] I didn't say that the EOR doesn't have to review shop drawings. I said that the EOR doesn't have to stamp and sign (with their engineering seal) the shop drawings. They typically do have a responsibility to review shop drawings for general conformance with the contract documents. If the shop drawings are part of a delegated design, they have more responsibility, in my view, to review and ensure that the delegated engineer made the right assumptions, used the correct loads, applied the correct code requirements, etc. [/green]

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[WoodDesignCat]

It sounds like we should not be accepting plans that are not well defined, even if they are approved, and shouldn't be accepting contractor review of engineering plans. Do you know of any codes that make this more clear, or things that I can reference to give this opinion more weight?

 

[JAE]

The building codes tend to stress the requirements for the technical aspects of a structure. The contractual, ethical, and standard practice issues are usually dealt with by the region's authority over engineering practice as well as various material entities (i.e. AISC's Standard Code of Practice).

If the EOR doesn't say much about the structural elements that you are providing - and if I were in your shoes - I'd always be attempting to push the design back to the EOR to review, comment on or approve if you don't have a licensed engineer stamping/sealing your work. And even if you do have an engineer - I'd still request the EOR to review and approve.

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