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RE: Metal Building Notes and Other Gripes

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Keith,
First I will start off with the fact that I don't personally recognize the
mentioned notes as coming from any of the MBMs that I have worked for... but
I will try to explain them based upon my experiences in the PEMB world.

> "In case of discrepancies between [Metal Building Manufacturer's]
structural
> steel plans and plans for other trades, [MBM's] shall govern ("Code of
Standard
> Practice for Steel Buildings and Bridges" in the AISC Manual Section
3.3)."
>
> My reading of this does NOT include metal building drawings, since Design
> Drawings are part of the Contracts Documents, which do not include metal
> building drawings.

Assuming this note is on the MBM drawings you may want to interpret it this
way...  The MBM drawings could be considered a "contractual document" from
the PEMB company to their customer (typically a GC, general contractor).
What this statement is trying to imply is that the supplied drawings show
how to put together the supplied parts (PEMB) and that other trade's
documents may not show the correct details or sequences.  The role that the
PEMB company typically gets into is being a material "supplier."  This is
often because the PEMB company is not in the direct loop and may not even
know who the other suppliers are.  Our contracts are with the GC (or maybe
an sub-contractor or erector)... i.e. we provide what they want [order] over
what any specific set of documents prescribe... (customer is always right...
at least most of the time :-) ).  If they order the building as per specs
(and possibly include the specs with the order) then that is the building
they get... if they decide they want alternate designs/details then that is
what they get... Assuming that is meets or exceeds the required codes OR
they have a signed and sealed letter excepting a specific requirement from
our responsibility.

> Most of these notes that anger me are clearly directed at the general
> contractor, but this standard of practice makes it increasingly difficult
to
> work with metal building manufacturers.

I really don't know how to respond to this one.  This standard of practice
[my drawings show how to put up my stuff] seems to be a reasonable approach.
I would not want a HVAC drawing to move a beam that we designed or one that
you designed.  Biggest issue I could see here is if the GC ok's an alternate
[structural] framing method and the communication never makes it back to the
other groups working on the project.  This seems more like a GC issue than a
PEMB issue.  I could not even count the number of times that the Arch.
[spec] drawings were put together so poorly that no building could have ever
been put up that way... (12" columns supporting huge loads with long spans,
open walls with no way to laterally brace for wind or seismic loads, clear
heights or widths that are physically impossible unless the shown 12" member
works, etc...)  The note also catches those errors (or omissions)... keeps
everyone from having to wait for another set of drawings to be completed
from the EOR or Architect.  With that in mind... if they ask us to wait for
those new drawings or specs... we will.  Our intention is not to say "we are
right and you are wrong," the intention is to get the right parts put in the
right spot using the right methods.

> Also, I appear to be fighting a losing battle insisting Metal Building
> Manufacturers design and supply anchor bolts.  It does not seem reasonable
to
> push design responsibility for building frame anchorage to another
engineer who
> must then interpret the numerous load combinations and determine those
that
> govern design.

First, some MAY provide this service... We provide [supply] the specificied
anchor bolts (rods) but do not design them (i.e. embedment length, etc.)...
some may even design the rods and foundations (*SOME*).  A couple of reasons
that this is not seen very much:
1) Typically the PEMB engineer does not make a trip to a specific job site
2) since #1, PEMB engineer may not have specific information or have access
to soils reports etc.
3) since #1, PEMB engineer has little to no quality control over local
concrete supplied
4) prevents PEMB company from placing foundations (hiring crews to place
concrete), doing proper inspections (requires site visits)
5) Might be able to tie into the slab or other concrete on the site (which
PEMB has little to no knowledge of)
6) Mainly distance... Someone actually at the jobsite would be able to
better manage the foundations.

Depending on which PEMB company you work with the reactions may come in
different formats.  Many tend to give the reactions from specific load types
(dead, collateral, live, snow, wind, etc.)  This is mainly due to the
different methods for calculating concrete capacities and prevents us from
guessing at which combinations either ACI or other codes may require... This
also allows the individual reactions to be factored as desired per the
engineer/code/etc.  Almost as easy as adding them up.  Some provide
pre-computed combinations also.. typically these are the combinations used
for the steel design and may or may not directly translate to the foundation
designs.

> What I would like, if I am FORCED by an architect or design-build
contractor to
> incorporate a metal building into a building design, is to work on the
> foundations only, and ignore the remainder of the building design.  But
when I
> begin thinking this through, it occurs to me that the metal building
> manufacturer might as well do the foundation, too.  Is this the intention
of
> various metal building drawing notes and contracts: create an environment
that
> is hostile to consulting engineers?  For example:
> 
> "[MBM] is responsible only for the structural design of the metal building
> system it provides.  [MBM] or [MBM's] Engineer is not the Design
Professional
> or Engineer of Record for the Construction Project.  [MBM] is not
responsible
> for the design of any components or materials not provided by it or their
> interface and connection with the metal building system."

No the intention if not to create a hostile environment to consulting
engineers!
Note 1) Why would anybody want to be responsible for anyone else's design...
not to even mention the legal aspects of what the states require for direct
supervision of a design for sealing purposes.... note as written is not
exactly true, PEMB is also responsible for any warranties that it may have
regarding its supplied components.
Note 2) Key word(s) "Engineer of Record" those 3 simple words have some
major liability tied with them.  Could include site visits, responsibilities
for other trades, etc...
Note 3) Similar to Note 1.  Again the goal here is NOT to be antagonistic.
Just stating again that what someone else provides is out of our control and
therefore we are not responsible for their acts (or lack thereof).

> While reasonable on its face, the above note sets up a terrible situation
for
> general contractors and building owners, not to mention structural
engineers. 
> Wherease is most projects we can design the building and then follow
> construction progress to verify compliance, metal building drawings and
design
> practice is rapidly moving toward forcing engineers to continue their
design
> work after construction has begun.  If there are any delays, it becomes
the
> design engineers fault (even if the blame is eventually assigned
elsewhere),
> and our reputations are reduced.

Presumably the design work would be done before the construction work
begins.  Exceptions to this might be "fast track" type of work which
requires the PEMB reaction in days after order so foundations can be
designed and placed... (i.e. most buildings may take longer to design...
what this does is get the PEMB to quickly design the frames (& reactions),
maybe even over conservatively, then go back and handle other issues on the
design assuming the conservatism on the front end will be enough to cover
unforeseen obstacles or changes).  Other exceptions might be the design or
detailing of connections between the PEMB and other components.  With
cooperation and communication up front this can be done prior to
construction.

Suggestions:
1) Work with reputable PEMB companies.
2) If you can, work up front with the PEMB companies (and their customer,
contractor or erector)... we don't like to do post construction design
anymore than you do...  We like to design it once and get it right
3) For changes we need to have our customer sign off on the changes.  Make
sure to work with or through them to avoid the feeling of getting the run
around.  Like other suppliers we need to provide what the customer wants.
4) Have problems with them... tell them so that it can be fixed or explained
5) If you don't like their answer tell them you don't like it.

Hope this helps explain the other side...  (too long of comments though)
Respectfully,
Greg Effland, P.E.
KC, MO USA

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