Closed and open specifications

What exactly are they, and how should engineers specify products or systems with the four different types of specifications?


Deciding among the four types of specifications—descriptive, performance, reference standard, and proprietary—and choosing how the specification is going to be written is only the first of many design decisions engineers make when starting to edit what will become a project specification, especially when specifying proprietary systems or products. There are two ways to specify a product in a proprietary specification: closed or open.

A closed proprietary specification names, describes, and lists a single product or system. The specification may list only one manufacturer or a product by one manufacturer, or it could list the single manufacturer or product and provide a list of other manufacturers or products that are options (note that options differ from substitutions, which will be discussed later).

An open proprietary specification describes a single product or system but allows the bidder to suggest an alternate or substitute product.

The correct use of alternate, option, and substitution is important when writing proprietary specifications as each has a fundamentally different meaning. An alternate is a product acceptable to the engineer or specification writer for which the bidder submits alternative pricing. An option is one of several, typically at least three, listed products in the specification. A substitution is a request to substitute one product for another product described in a specification. This could be in the form of a proposed substitution, where the specification do not name alternate products or manufacturers but allow submittal of substitute products, or a controlled substitution, where the desired products or systems are described and named, but substitute products with equal functionality may be submitted for review and approval.

Closed proprietary specifications name one product or several products that are allowed as options, but do not use substitutions. This provides the engineer and owner with complete control over the products, which can significantly decrease the time spent researching and reviewing products and manufacturers, and can allow for greater detail on product or system drawings. It also streamlines the development of the specifications, as simply naming a product using the manufacturer's ordering code, or naming the product and describing the desired options, may be all that is required to complete Part 2 of the specification. The bid process is also simplified: Rather than researching and submitting products to the engineer for review, there is only one manufacturer or several manufacturers to contact for pricing, and the manufacturer typically well understands the client's needs.

If you choose a closed proprietary specification, note that this method limits competition, which may result in increased cost or long lead times. Additionally, the number of bidders with the required experience or certification to install the system may be limited. Also note that this method requires the engineer to specify the exact product that the owner wants, and any mistakes made when specifying the product are typically directly attributed to the engineer.

For federal projects, or projects requiring at least three options for each product to ensure fair and competitive bidding, use of a closed proprietary specification that names only one product is called sole sourcing. This may be required for some products or systems that require significant engineering work or compatibility with an existing system. You should be prepared to substantiate this decision.

An open specification that allows alternate products is similar to a closed specification in that it describes a very specific product and may name only a single product or manufacturer. However, open specifications include provisions that encourage the bidder to submit alternate or substitute products. If alternate products are requested, a list of the approved alternate products is included in the specification. The bidder must submit pricing for the named product and is permitted to submit alternate products from the list included in the specification, along with pricing information for the alternate products.

Open proprietary specifications that allow substitutions name only a single product, but include provisions within the product specification that allow the bidder to submit substitute products. The bidder chooses to submit pricing for either the named or base bid products or any products that the bidder feels would meet the requirements of the named product. A product that is submitted as a substitute product must have the same functionality and the bidder must include pricing information.

Occasionally, you may come across an open specification that allows controlled substitutions. This differs from a specification that allows substitutions in that it includes a requirement to coordinate the substitution request with the requirements for product substitution in Division 01, typically in a section called "Product Substitution Procedures." What this means to the engineer is that substitutions are not directly addressed in the product specification, but instead may be submitted, reviewed, and used as long as the bidder complies with the requirements for substitutions in Division 01. This means less work addressing the substitution procedures, but requires the engineer to write a strong specification that adequately details the desired characteristics or operation of the product.

All open and closed specifications, except for an open specification that allows controlled substitutions, require that the engineer work with the owner or contracting officer to ensure that provisions for the alternate or substitute products are included within the bidding forms, since submission of these products typically includes a difference in bid price. However, no special requirements are needed for an open specification that allows controlled substitutions since the requirements for submittal of a substitute product are addressed in Division 01.

Michael Heinsdorf, PE, LEED AP, CDT is an Engineering Specification Writer at ARCOM MasterSpec. He has more than 10 years of experience in consulting engineering, and is the lead author of MasterSpec Electrical, Communications, and Electronic Safety and Security guide specifications. He holds a BSEE from Drexel University and is currently pursuing a Masters in Engineering at Drexel University.

Consulting-Specifying Engineer's Product of the Year (POY) contest is the premier award for new products in the HVAC, fire, electrical, and...
Consulting-Specifying Engineer magazine is dedicated to encouraging and recognizing the most talented young individuals...
The MEP Giants program lists the top mechanical, electrical, plumbing, and fire protection engineering firms in the United States.
How to use IPD; 2017 Commissioning Giants; CFDs and harmonic mitigation; Eight steps to determine plumbing system requirements
2017 MEP Giants; Mergers and acquisitions report; ASHRAE 62.1; LEED v4 updates and tips; Understanding overcurrent protection
Integrating electrical and HVAC for energy efficiency; Mixed-use buildings; ASHRAE 90.4; Wireless fire alarms assessment and challenges
Power system design for high-performance buildings; mitigating arc flash hazards
Transformers; Electrical system design; Selecting and sizing transformers; Grounded and ungrounded system design, Paralleling generator systems
Commissioning electrical systems; Designing emergency and standby generator systems; VFDs in high-performance buildings
As brand protection manager for Eaton’s Electrical Sector, Tom Grace oversees counterfeit awareness...
Amara Rozgus is chief editor and content manager of Consulting-Specifier Engineer magazine.
IEEE power industry experts bring their combined experience in the electrical power industry...
Michael Heinsdorf, P.E., LEED AP, CDT is an Engineering Specification Writer at ARCOM MasterSpec.
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me