Pre-Engineered Metal Building Engineer: SSE or SER? 2

[tonyoo]

I am a structural engineer working for a design build firm which provides construction management and engineering services under one roof.

If a building is a conventional steel building, then I design the steel, foundations, slabs on grade, masonry, etc, I am the structural Engineer of record.

However, if the building is a pre-engineered metal building, or a pre-cast building, I only design the foundations, slabs on grade, masonry, etc. A "specialty engineer" designs the structure and provides footing loads to me.

Who is the Structural Engineer of Record in the PEB or Pre-Cast case?

I have seen definitions of SER being the engineer who has responsible charge of the Primary Building Structure (PBS). PBS being defined as the completed combination of structural elements that serve to support the building's self weight, live loads, and environmental loads.

Thanks for your opinions!

 

[JAE]

For both pre-engineered metal buildings and precast buildings, we serve as the EOR even though we only do the hands-on design of the foundation.

The key here, I think, is that beyond the foundation design, we also do a lot of other "global" chores and have ultimate responsibility for all the components fitting together. Here's a list of services that we do as EOR, that the pre-engineered building folks do not do:

1. Coordinate and fix the overall layout of the building in conjunction with the architect.

2. Coordinate, identify and resolve requirements for structural support of mechanical and electrical equipment. This may involve only locating and indicating required loads and openings.

3. During design, understand and accommodate the overall lateral bracing system of the building. This doesn't mean you design the braces, or moment frames, just that you develop the plan of action for it and communicate that to the bldg. mfr.

4. Indicate in the plans the required codes, live loads, lateral loads, stiffness requirements, and any other design criteria that you are using and that you wish the building manufacturer to use.

5. Request and coordinate the geotechnical report and indicate on your plans the resulting recommendations, including seismic site data for lateral design of the building.

6. Communicate with prospective building manufacturers to obtain typical details of the framing to coordinate with your and your architect's details.

7. In some cases, we design bridge cranes, jib cranes, and other similar fixtures and indicate those applied loads on our drawings to the building manufacturer.

8. Review the building manufacturer's drawings and calculations to verify that they have properly incorporated all loadings and design criteria.

9. Verify that the building was designed by a properly licensed engineer.

10. On-site observations of the construction to verify general conformance with the plans and specifications.

11. Processing of all submittals.

I'm sure there's more beyond the above but it gives a sense of the services that should be provided...which is more than the building manufacturer does. Simply because you are designing a smaller physical portion of the building, doesn't mean that you shouldn't be the EOR. In fact, I believe that most of these pre-engineered companies don't want to be the EOR, and many probably don't have the type or level of insurance that private practice firms have.

 

[JStephen]

I think JAE pretty well summed it up.

I might point out that some states define the engineer-of-record and relationship between that engineer and others, and some states simply don't define any of this.

I work for a specialty contractor. We furnish PE-sealed plans for our product, and generally expect the owner's consultant to do the things JAE has outlined (in our case, this will usually be a civil consultant, not structural). On the occasional jobs where there is not a consultant involved, that leaves us trying to track down the building codes and some of this other information for a particular area.

 

[tonyoo]

Thank You both, that was very helpful!

 

[RARWOOD]

Good question tonyoo.

I run into similar problems at my job.

Simple example we sell a octagon pinic shelter constucted using arches and glulam beams. We provided the foundation loads, but don't design the foundations.

The shelter is a standard shelter where a draftsman changes the title block and reprints the drawings.

Later after the shelter is in place I might call the owner to find out who the EOR is because I have a question about the foundation. Often times I am told that I am the EOR.

I am not the EOR, I have not certfied any drawings and I didn't design the foundation. Now the state comes along and indicates they require sealed drawings for the shelter and foundations.

I now learn that the architect drew the foundation plans. In Minnesota an architect who is not a PE, can't practice engineering.

So now what?

If the orginal contract documents required certified shelter plans, the company I work for, would have hired an outside engineer to prepare the plans.

However after the fact in Minnesota you can't hire an engineer to certify plans which were not prepared under his or her, direct supervision.

If push comes to shove one of the PE's at the company I work for could certify the shelter plans but not the foundations.
We use outside consultants because we don't carry errors and omisions insurance.

 

[JStephen]

RARSWC, the solution in your case is to try to nail that down ahead of time, since you know it's a potential problem.

We run into similar issues. There will be a foundation drawing on the plans, with all the rebar sizes and foundation dimensions shown, with a PE seal on the drawing. Then in the specifications, it says the contractor is to design the foundation, and that design is just "typical" or "the minimum foundation". When you ask questions, it's about a 50/50 split as to whether someone gave it some thought and designed it or just slapped a detail on and assumed we'd do the design. If there's any ambiguity, ask, and don't be afraid to tell them why you're asking.

 

[haynewp]

I would be interested to know how the EOR usually fairs when there is litigation over a metal building collapse. In the case of other specialty products; steel joists, pre-fab trusses etc., I understand the EOR is the first target if there is a failure of that product even if it was not his design.

Also, regarding the state engineering boards. Is the EOR usually penalized when there has been negligence on the part of the metal building engineer? I can see doing a general design criteria review of the metal building engineer's work, but we can't possibly be expected to check every part of the design of a metal building when they are using their own in-house developed programs. And how far do CYA notes about the metal building design really go when YOU are the EOR?

 

[RARWOOD]

JStephen

You bring up a very good issue concerning the drawings which have an engineering seal, and state that the details are typical or just minimum. I see that on a lot of drawings.

I design in wood, so the problem I have is that in most cases when I review the design the members aren't minimum sizes, but are over sized. Now in some cases the members are oversized because the architect wants exposed beams of a certain size. However in most cases the sizes are larger because the designer is not familair with wood design.

So in the end our erection plans duplicates the structural plans. This only becomes a problem when the EOR requires that the shop drawings be certified. In this case the EOR is asking another engineer to certify his design, which is not allowed in most states.

One job, I worked on required certification of the glulam truss shop drawings. This was required despite the fact the truss spacing, truss profile, member sizes, truss plate configurations, truss plate thickness and size and number of fasteners required, where shown on the plans.

The only thing remaining was determining the bolt spacing. The EOR justified his requirement by stating that the truss members where minimum and the details were typical.

 

[frogit22]

My firm does foundation design for metal buildings (we are a consulting structural engienering firm)

When we do a statement of special inspections for metal building jobs, we list two SER's. We list our PE for the SER for foundations and the metal bldg company's PE as the SER for the buidling.

So far nobody has complained.

 

[RARWOOD]

I will check with the Minnesota State Board, but I think in most states a building is required to have only one EOR.

For example a metal building blows away becuase of a poor foundation design does the metal building engineer walk away from the problem because the foundation was designed by another engineer.

Or is the metal building engineer required to check the foundation design to assure the building won't blow away.

Another problem is the fact that the foundation engineer is working for the owner or owners architect. The metal building engineer is probably working for the general contractor.

In your case who specifies the building design loads?
In the work I've been involved in, where the consulting engineer designs the foundation he or she also specifies the design loads.

If I were to design a structure to fit on the foundation for such a project, and be considered as the EOR for the structure possible problems would arise.

For example if I disagree with the design loads, I have to deal with the foundation engineer. While the foundation engineer has the ability to talk to the owner about the design loads, I would be restricted from doing that.

 

[JAE]

I agree with RARSWC on this. A building should (must?) have one EOR.