ConstructionPro Week, Volume: 4 - Issue: 2 - 01/16/2015

Distinguishing Trade Custom from Trade Standards

By Bruce Jervis


Construction contracts make extensive use of trade standards when defining the work. It is common for contracts to utilize or reference industry manuals, standards or specifications. But these objective standards are not the same as “trade custom.”


Trade custom is sometimes used to interpret, or understand, trade standards which are used in a contract. It is important to remember, however, that customary practice in the field, no matter how prevalent, cannot alter or supersede the express language of the contract documents.


This principle was illustrated on a recent federal construction project. The drawings and specifications unambiguously described a work requirement, albeit in a manner which arguably deviated from trade practice. The drawings and specifications prevailed. They could not be altered by trade custom.


What has been your experience? Are contract terms sometimes so vaguely or poorly drafted that it is necessary to resort to trade custom? Or, are contractors quick to rely on customary practices to the detriment of express requirements in the contract? I welcome your comments.




This is actually a very interesting question. Our experience is that contractors rarely argue where the contract documents specifically express a standard that is above "customary". However, there are a multitude of instances where the documents may be silent on the anticipated standard. In those instances contractors do try to impose their version of what is acceptable. We see this most in the inspection of things like painted drywall, concrete,glass and coated aluminum, where the trade's published version of a finish guideline requires inspection from distances that are far greater than the surface may normally be viewed from and require inspection only at 90 degrees to the surface. Even where the standard is more of an industry standard, such as ACI or ANSI based, the standards can be quite loose. So understanding what's in the reference standards and specifying a higher standard where appropriate should be a part of every project's construction document process.
Posted by: John Christiansen - Friday, January 16, 2015 4:49 PM

I agree, most specs are either too broad or too nebulous. It is fine to reference specific standards if they are project items specific - but to just reference "trade custom" doesn't cut it.

I have seen somewhat similar terms in the AV industry, such as "as per InfoComm standards" which are also a bit vague. I do however support phrases such as "all assembly and installation methods to be in accordance with InfoComm standards and AV industry best practices". The term "industry best practices" carries a bit more weight, especially when referencing the specifics of assembly and installation. It also helps that the AV industry has fairly clearly defined methodology, guidelines and standards for just about all aspects of an AV project.
Posted by: Christopher Maione - Sunday, January 18, 2015 9:55 AM

Where the 'trade custom' really gets to be a problem is when the owner or architect are from a different geographic region. Custom tends to vary from region to region. So, what the contractor might expect to be customary where he lives, the owner where he lives, the architect where he lives, and the building inspector where the work is being done can all be different.
Posted by: Billy Cordova - Monday, January 19, 2015 10:00 AM


WPL Publishing - 5750 Bou Avenue #1712 - Rockville, MD 20852

Phone: (301)765-9525  -  Fax: (301)983-4367

All Content and Design Copyright © 2021 WPL Publishing
About Us

Contact Us

Privacy Policy

My Account