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Shannon Toranzo (Unregistered Guest)
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Posted on Tuesday, June 30, 2015 - 05:54 pm:   Edit PostDelete PostPrint Post

Hello,
I am a general contractor and have a situation where the client named their basis of design for some casework and lab equipment, then named other "acceptable" manufacturers. No one bid from the BOD supplier, only one named "acceptable" manufacturer bid.

Once awarded the project, the client stated that the standard dimensions for the "acceptable" manufacturer were not acceptable, now requiring a custom design and special testing. No where in the specifications did the client list specific dimensions that were required. They only listed performance requirements in the specification, which the product meets. They claim that by naming the BOD, the manufacturer must match the exact dimensions. Each manufacturer has slightly different dimensions and cannot change up their designed and tested product for one client, unless specified to do so.

Who is responsible in this case? GC or Client/Architect? Appreciate any insight you can provide.
Lynn Javoroski FCSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 2030
Registered: 07-2002


Posted on Tuesday, June 30, 2015 - 06:08 pm:   Edit PostDelete PostPrint Post

Are there dimensioned Drawings? If so, the dimensions have as much import as the specifications. Dimensions are usually not in the specifications, since they are better graphically represented.
Nathan Woods, CSI, CCCA, LEED AP
Senior Member
Username: nwoods

Post Number: 680
Registered: 08-2005


Posted on Tuesday, June 30, 2015 - 09:34 pm:   Edit PostDelete PostPrint Post

Shannon, this is a common scenario, certainly in public work when sole sourcing is not permissible. Basis of Design is a very important term. What that means is that the Owner says, this is what I want. The Architect and Engineers then incorporate that into their designs, using all the parameters and requirements particular to that BoD element. Essentially, if a contractor submits something other than the BoD element, its a substitution, because the design wasn't intended to accommodate its unique parameters. Roll up doors is a good example. A McKeon motor assembly is more compact than say, a Cookson, and if a contractor submits a cheaper Cookson, it may totally mess up any related soffit or ceiling conditions, and even the motor amperage can be different. Equal? Maybe, different? Definitely! Should the A/E be forced to change their design just because the law says to list more than one mfr? Heck no! They only get paid to design it once, and the Owner wanted McKeon so that’s what the Architect based its design on. The only party getting the benefit from the substitution is the contractor, so that is the party that should pay for any related effects the change in mfr's creates.

In your exact instance, it’s possible that an accommodation can be made, that the critical dimension only applies to a limited part of the casework. But if not, the dimensions are in the plans, and the mfr’s that bid on the casework is bound to deliver on the requirements in the plans. Here’s another example; the specs don’t say the basis of design is a Toyota Tundra, and the contractor submits based on a Toyota Tacoma, thinking they are both quality trucks, with four wheels and a pickup bed, with similar warranties. But the bed on the Tacoma is longer, and has a much higher tow capacity. The Owner can’t use the Tacoma, no matter how good it might be, its not the same. It doesn’t meet the criteria of the documents.
Dave Metzger
Senior Member
Username: davemetzger

Post Number: 592
Registered: 07-2001


Posted on Tuesday, June 30, 2015 - 10:11 pm:   Edit PostDelete PostPrint Post

The designer's and specifier's responsibilities require more than just listing a product and manufacturer name, labeling it "Basis of Design", and thinking that is an adequate specification. They also need to specify just what criteria are important to the design and will be used to evaluate proposed substitutions--ie the "salient characteristics". In Shannon's example above, if the casework and equipment dimensions were critical, then the salient characteristics, specifically "dimensions as indicated on Drawings", should have been specified. Otherwise, how can bidders know what characteristics of the BOD product are important--dimensions? color? drawer pulls?

This cuts two ways, if you think of salient characteristics as silver bullets--they are what the specifier can rely upon to reject non-compliant specification requests. But it does mean coordinating between the designer and specifier upfront as to what is really important to the design.
ken hercenberg
Senior Member
Username: khercenberg

Post Number: 924
Registered: 12-2006


Posted on Tuesday, June 30, 2015 - 11:10 pm:   Edit PostDelete PostPrint Post

Dave, I don't refer to the Drawings in my technical sections, only in Division 01 and that's when it's not clearly defined in Dividion 00.

Were the dimensions shown clearly on the Drawings? I have to presume the bidders had to refer to the drawings to establish quantities. Did they think the dimensions were there just for the heck of it? Perhaps it would have been nice if the specs identified that custom sizes were required but, if shown, it sounds like the bidders didn't estimate properly and are now scrambling.
Dave Metzger
Senior Member
Username: davemetzger

Post Number: 593
Registered: 07-2001


Posted on Wednesday, July 01, 2015 - 09:03 am:   Edit PostDelete PostPrint Post

Hi Ken:

It's been more than 30 years since I've laid out lab casework and equipment, but my recollection is that casework dimensions were pretty standard across the industry; in increments of 3 inches for cabinet lengths if I remember correctly. And filler panels to close the gaps to adjoining construction. So I don't understand what would be so critical about the design being based on the standard dimensions of just one particular manufacturer.

That said, I do agree that if the design was so specific as to require custom dimensions from manufacturers other than the BOD, the salient characteristics should have stated that custom cabinet dimensions may be required to provide the exact dimensions indicated on the drawings. I prefer to try and anticipate what could go wrong and then word the specifications to forestall such pitfalls--that would avoid the pi---ing contest that appears to be developing in this case.
Dave Metzger
Senior Member
Username: davemetzger

Post Number: 594
Registered: 07-2001


Posted on Wednesday, July 01, 2015 - 09:09 am:   Edit PostDelete PostPrint Post

As a follow-up, how do you know what to anticipate and what could go wrong? It's having been burned before (that's called experience) and it's where the gray hairs of most of the participants in the 4specs forums come from. I also try and put myself in the mindset of "how can the drawings and specifications be deliberately misinterpreted to the contractor's advantage?), and then try and guard against that.
Greta Eckhardt
Senior Member
Username: gretaeckhardt

Post Number: 16
Registered: 08-2013


Posted on Wednesday, July 01, 2015 - 02:06 pm:   Edit PostDelete PostPrint Post

I would say that specifying a Basis of Design product, according to the excellent process described by George Everding at the beginning of this discussion, is a good solution to several things that have changed in our profession in the last decade or two. There was a time when an office could identify three equivalent products for most of the work on most of their projects, based on familiarity and experience, and these products could be listed in office masters. We now have:

* Proliferation of types of products or materials, each manufacturers with their own unique version of those materials, some changing from year to year

* Shortened project schedules

* Increased range of performance criteria that need to be addressed to meet aesthetic, Code, sustainability, Owner standard and other project goals.

By finding - within the time available - at least one product for which there is adequate information to convince us that it meets the criteria, I think the designers and specifiers are often doing about the best they/we possibly can. Specifiers generally believe that it is in the Owner's interest to allow for competitive pricing, so we try to list other acceptable manufacturers or products but nothing seems to be "equal" any more.

The identification of salient characteristics is really critical to defining "comparable" or "equivalent" and should be part of the designer/specifier dialogue from the beginning.

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