Substitution Requests and the Or-Equal Clause

Part 2 of the spec names three PLC manufacturers "or approved equal." You have a fourth in the shop, on your standards, with better pricing. So you build the panel package around it, mark the datasheets, and send it in. It comes back Rejected, with one line: substitutions will not be considered when indicated on shop drawing or product data submittals without a separate written request. Three weeks gone, and the request you should have filed in week one now starts in week four, against a reviewer who has already said no once.

The or-equal clause is not an invitation to submit whatever meets the spec. It is a door with a procedure on it, and the procedure lives in Division 01.

Named manufacturers and the or-equal clause

Specs name products in a handful of patterns, and the pattern decides whether you need permission:

Reference standard, performance, or description only. No manufacturer named. Any product that meets the stated requirements is acceptable, and the ordinary submittal proves it. No substitution request exists to file.

Several manufacturers named, no "or equal." A closed list. Any of the named products is acceptable; anything else is a substitution, and some owners forbid substitutions on closed lists outright. One spec I hold, for items the owner has standardized on, reads simply: no substitutions shall be allowed.

Named manufacturer or manufacturers "or equal" / "or approved equal" / "or equivalent." The named products are acceptable as submitted. An unnamed product may be proposed as an equal, but the words carry an obligation. Under the standard engineer's general conditions, a proprietary name establishes the type, function, appearance, and quality required, and the engineer is the sole judge of whether something else is equal. Federal contracts say the same thing in their own words: a trade name establishes a standard of quality, and the contractor may use anything the contracting officer judges equal. Either way, the burden of proof is on you, and the decision is theirs.

Basis of design. Newer master specs name one product as the basis of design and let comparable products from listed manufacturers through the submittal process, while anything else is a substitution. Read the section's own article on comparable products; it says which.

One water utility spec I hold puts a number on the or-equal clause that surprises people: the owner will evaluate a maximum of one proposed or-equal product of each type, and if it is found not equal, the contractor provides the specified product at no additional cost. One shot, then the named product. That is the or-equal clause with its teeth showing, and it is not unusual.

The Division 01 substitution procedure

MasterFormat puts it at 01 25 00 Substitution Procedures, with the product-naming rules next door in 01 60 00 Product Requirements. Older books put both in 01600 Material and Equipment or 01630 Product Substitution Procedures. Some books skip the separate section and put the procedure in the general conditions or in the instructions to bidders. Find it before you propose anything, because it defines four things:

1. What counts as a substitution. The common definition is any change in products, materials, equipment, or methods of construction from those required by the contract documents. Many books split it into substitution for cause (the specified product is unavailable, discontinued, or no longer meets code) and for convenience (you would rather supply something else), and treat the two very differently.
2. When a request may be filed. Covered below; it is the deciding factor.
3. What the request must contain. Also below.
4. How it is answered and what happens if it isn't. Typically the engineer either approves, approves as noted, rejects and directs the specified product, or returns it as too late. Some master specs set a window for the decision and state that silence means use the product specified.

The distinction the general conditions draw is worth holding onto. An or-equal is a product so close that no change in related work is required, and it is closed by an approved submittal. A substitute is anything that requires a change elsewhere, and it is closed by a change order. If your proposed PLC needs a different rack size, a different power budget, or a different communication card in someone else's panel, it is a substitute whether or not the spec said "or equal," and it will need the full request.

What to attach

A substitution request that arrives as a datasheet and a note is a request that comes back "more information required," which costs a review cycle. The standard construction-industry substitution form, and the Division 01 sections modeled on it, expect all of the following:

• The form itself, one product per request, referencing the spec section and paragraph and the specified product by name.
• A point-by-point comparison of the proposed product against every requirement of the section's Part 2 and the specified product's salient characteristics. Same table, three columns: requirement, specified, proposed. This is the document the engineer actually reads.
• Product data for the proposed item, marked the same way any submittal is marked.
• The reason. Unavailability with a manufacturer's letter, a regulatory change, or, for convenience, the benefit to the owner: cost credit, schedule, maintenance. "We stock it" is not a reason an engineer can approve.
• Effect on other work: dimensions, clearances, power demand, wiring, other trades' drawings, and the cost of any redesign. At least one owner's section requires that revised drawings affected by the substitution be prepared and stamped by a professional engineer at the contractor's expense.
• Cost and schedule impact, stated as a number and a date, including a credit if the substitute is cheaper. Some forms waive later claims for cost or time related to the substitution once it is accepted.
• Warranty, service, and parts equal to the specified product, with the local source named.
• Certifications the section demands, listing and agency marks included.
• The contractor's signed statement that the substitute is equal or superior, has been coordinated with the work, and that the contractor will pay any redesign costs. The standard form makes this a list of eight certifications over a signature.

Attach all of it the first time. The evaluation is a comparison, and you are the one who has to make the comparison possible.

Before bid versus after award

Timing is the variable that decides more substitution requests than merit does.

Before bid is the cheap window. Instructions to bidders commonly accept requests for prior approval up to a stated number of days before bid opening, answer them by addendum, and make the decision final. A product approved by addendum is now a named product, and every bidder can use it. The cost of asking is a form and a week; the benefit is a package that goes in as a plain submittal.

After award is the expensive window, and it closes fast. Real specs set it at ten days after notice to proceed, thirty days after the contract's effective date, or a fixed number of days before the related submittal is due, and after that many books allow substitutions only for cause: unavailability, discontinuation, or conditions beyond the contractor's control. Several master specs simply say substitutions for convenience are not allowed after award, at all. The general conditions on the engineer's side won't even consider an or-equal application until after the agreement is signed, so the bid-stage window and the post-award window are different doors with different rules.

The trap sits between the two. You bid with the fourth manufacturer in mind, meaning to sort it out later. "Later" is after award, when the request is for convenience, the window may already be shut, and the engineer's easiest answer is the named product. The reading of the spec section that finds the named-manufacturer list and files the prior approval request before bid is described in how to read a spec section for submittal requirements.

When it becomes an RFI

Not every question about a named product is a substitution. It is an RFI when the contract documents cannot be read to say what is required: a listed product line has been discontinued and the section was never updated, two paragraphs name conflicting products, the named model cannot do what Part 2 demands. Ask the question, cite both places, propose the answer. The engineer answers an RFI by clarifying or supplementing the documents, which is a different act from approving your choice.

Two rules keep the channels straight. An RFI is not the way to request approval of a substitution; at least one owner's RFI section says so explicitly and rejects RFIs used that way. And a discontinued product is handled as a substitution for cause with the manufacturer's letter attached, not as an RFI, unless the spec's own list is internally inconsistent. The broader judgment is in submittal versus RFI.

What a rejected substitution costs

The procedure exists because the downside is asymmetric. If the request is rejected, or never filed and the submittal is bounced for it:

• You furnish the specified product, at the contract price. Every spec says this, and the standard general conditions make an unapproved substitution defective work.
• The engineer's evaluation time is yours to pay for whether or not the substitution is accepted, and the redesign it causes is yours once it is, in the usual Division 01 language.
• The schedule stays with you. A review cycle spent on a substitution that fails is a cycle the procurement chain was waiting on; see sequencing submittals against lead times for what a lost cycle does to an order date.
• Anything you ordered early is your risk. Return and reordering are named as the contractor's cost in at least one book, and federal language puts unapproved items "at the risk of subsequent rejection."

Against that, a prior approval request before bid costs a form. The arithmetic is not close.

One example

Section 40 61 13 Part 2 names three PLC platforms "or approved equal." The integrator's standard is a fourth. Two ways the job goes:

Same spec, same product, same integrator. The difference is a form filed in the right week.

Disclosure: I build Submittal Kit, whose spec check reads each datasheet against the linked section and flags a manufacturer that is not on the section's list before the package goes out. The request itself, and the week it has to be filed, come from Division 01 and no software changes that.