AEC definitions

What Is a Performance Specification?

Last reviewed: September 2026

A performance specification states what the finished work must achieve: a structural capacity, an acoustic rating, a U-factor, a clearance. It does not dictate the product or the method, as long as the result is met and demonstrated. A prescriptive specification names the products and the installation.

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States
A measurable result
Leaves open
The product or method, within the criteria
Opposite of
A prescriptive specification, which names the product
Common on
Design-build and delegated-design scopes
Proof
Tests, calculations, or certifications the section names
Mixed specs
The usual case in design-bid-build project manuals

Definition

Performance specification

Most project manuals mix the two. A section may prescribe a standard and a manufacturer list, and also require a performance value. Pure performance specs are common in design-build and in delegated design, where the contractor's engineer has to meet criteria the owner set. The risk sits in the tests. If the spec does not say how performance is proven, the submittal becomes an argument about whose lab and whose assumptions count.

In depth

Performance and prescriptive, on purpose

Prescriptive text says install this membrane, in these laps, from one of these manufacturers. Performance text says the roof assembly shall meet a stated uplift and a stated thermal value, and shall carry a warranty of a stated term. The first is easier to review. The second is how you buy an outcome when you do not want to design the means.

Unintentional performance language is the problem. 'Or equal,' with no criteria for equal, is not a performance spec. It is an invitation to substitute downward.

Say how the result will be shown

Name the test standard, the design loads, the calculation method, or the certification. A sentence that says 'high performance' cannot be enforced. A sentence that cites a standard can.

Submittals for performance items include engineering, test reports, or both. Review time in Division 01 has to allow for that, not only for a catalog cut.

Delegated design is performance plus a seal

Stairs, cold-formed framing, curtain walls, and firestopping are often delegated. The specification states criteria and requires a licensed engineer to seal the shop drawings. The architect reviews for fit and appearance. The delegated engineer is responsible for the performance they sealed.

Criteria that are incomplete, such as a drift limit nobody stated, come back as an RFI. Write the criteria in the section, not in a meeting.

Design-build lives on performance

The owner's request states performance. The design-builder's proposal says how they will meet it. After award, the criteria remain the ruler. A beautiful system that misses a stated acoustic rating does not meet the spec because the architect liked it.

Changing a criterion after award is a change. Discovering that the criterion was never measurable is a dispute about the solicitation.

Review against the criteria, not against taste

A reviewer who rejects a performance submittal because it is not the product they had in mind, when the product meets the written criteria, is rewriting the spec during review. If the product was supposed to be prescribed, prescribe it.

A reviewer who accepts a catalog cut that never addresses the criterion has not reviewed the submittal. The response should say which criterion was shown and which was not.

Examples

Performance specification on a real project

  • 01

    A curtain-wall section requires a stated U-factor, a water-penetration test, and a delegated engineer's seal. It does not name the mullion system.

  • 02

    A prescriptive paint section names the system and the sheen. Performance language is limited to the surface preparation standard.

  • 03

    A design-build acoustic criterion of STC 50 is in the owner's request. The partition submittal includes a tested assembly that meets it.

FAQ

Frequently asked questions

It is specification language that requires a measurable result and allows any product or method that meets it and can prove it. A prescriptive specification names the products and the installation.

It tells the contractor which products, standards, and installation methods to use. Review checks conformance to that list. There is less room for an alternate approach.

When the owner wants an outcome and the contractor or a delegated engineer will design the means: design-build, and items such as curtain wall, stairs, and metal framing on design-bid-build jobs.

The numeric or tested criterion, the standard used to measure it, and the submittal that demonstrates it. Words like high performance, without a number or a standard, cannot be reviewed objectively.

Keep reading

Related terms and workflows

What Is a Specification in Construction?

A specification is the written portion of the contract documents. It states the quality, materials, standards, workmanship and administrative requirements that drawings cannot convey, and it is read together with the drawings as a single set of obligations.

What Is an Outline Specification?

An outline specification is a short, early description of the systems and materials a project intends to use. It is written during schematic design or early design development, before a full project manual exists. It is enough to price a concept. It is not the construction specification.

What Are Submittals in Construction?

A submittal is the package a contractor provides to the design team to demonstrate that the product they intend to buy, or the assembly they intend to build, matches what the contract documents specify. The design team reviews it and returns a review action.

Submittal review

Check submittals against the criteria the specification actually states.

Design-build contract analysis

Where performance criteria carry more of the contract than a prescriptive book.

What is a specification?

The document type performance language sits inside.

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What Is a Performance Specification? | Nomic