Construction Manager Contracts: CMa vs. CMc

Construction manager agreements and responsibilities

A construction manager can be an adviser or a constructor. The difference changes who holds construction contracts, who performs the work, and how the architect administers the project. Identify the contractual relationships before interpreting a payment, change, or coordination request. The title “construction manager” alone does not establish a guaranteed maximum price or make the manager responsible for building the project.

Construction manager as adviser

A CMa provides professional management services to the owner, such as scheduling, cost advice, procurement coordination, and constructability review. The owner holds construction contracts, often with multiple prime contractors. The CMa does not become the contractor merely by visiting the site or coordinating trade schedules. It can nevertheless be responsible for negligent performance of its own professional services; advisory status is not immunity from liability.

The AIA 2019 CMa family includes B132 for owner–architect services, C132 for owner–CMa services, A132 for the owner–contractor agreement, and A232 for the general conditions. A132 is an agreement, not the general conditions. Use the coordinated family rather than attaching an unrelated form and assuming its procedures are identical.

Coordinate joint administration

In a CMa project, the architect and manager have complementary administrative duties. Establish the actual routing of submittals, applications for payment, proposed changes, and closeout records. CMa coordination of trade packages does not replace the architect's review for design conformance. The architect's certificate is also not a substitute for the CMa's required review of contractor records and project coordination.

For example, separate roofing and mechanical prime contractors each believe the other will supply roof curbs. The PM should compare both contracts, specifications, and package boundaries, identify the gap, and coordinate a documented resolution with the CMa and owner. Quietly moving the work into one package without an authorized change can create price and warranty disputes. Track related flashing and structural supports rather than resolving only the purchase of the curb.

A232 procedures can involve approvals by both professionals. Read the actual instrument and required signatures before issuing it. Avoid invented form names such as “G704-CMa” or treating A201's ordinary three-party change procedure as interchangeable with every CMa procedure. Distribution and approvals should be established in the project documentation plan.

Construction manager as constructor

A CMc provides preconstruction services and subsequently performs construction through its trade subcontracts. Under a typical A133–2019 arrangement, the parties develop a GMP proposal. B133 describes the architect's services in that delivery method, and A201 governs relevant construction administration. A134–2019 provides a cost-plus-fee CMc agreement without a GMP, demonstrating why CMc and GMP are not synonyms.

Early contractor participation can improve estimates, sequencing, and procurement planning. It does not guarantee a lower price, faster completion, or a clash-free design. Review the proposed benefits against staffing, owner decision readiness, package boundaries, and the time available for design and quality control. The architect remains responsible for its professional services while the CMc controls construction means, methods, and its subcontractors.

Review the GMP basis

A GMP proposal should identify the drawings and specifications used, assumptions, clarifications, allowances, contingencies, fee, anticipated schedule, and exclusions. The architect reviews the proposal for consistency with the design documents and assists the owner within its scope. Match issue dates and revisions: a proposal based on SD drawings may not include systems selected during DD.

Assume a proposal totals $10 million but excludes a $300,000 owner-required laboratory system and carries only $150,000 for an envelope allowance expected to cost $250,000. The apparent total understates those known requirements by $400,000. Resolve the exclusions and allowance before comparing the proposal with the owner budget. The manager should not assume that the contractor contingency will absorb excluded scope without agreement.

A GMP is a contractual cap subject to its terms and permitted adjustments. Owner changes, applicable concealed-condition provisions, and other authorized adjustments can affect it. It is not an absolute promise that the owner can add work without changing price. Conversely, ordinary estimating mistakes within the contractor's assumed risk do not automatically justify increasing the GMP.

Distinguish reserves and review rights

Contractor contingency, owner contingency, and allowances serve different purposes. Define each in the agreement: what may be charged, who approves use, how expenditures are reported, and how unused amounts are treated. Owner contingency is generally outside the initial contractor price, but spending it does not always require a construction change; an owner might use it for a separate owner expense. A price-changing construction revision requires the applicable contract instrument.

Cost-plus administration requires appropriate records of reimbursable costs and the agreed fee. Audit rights belong to the owner and designated auditors as stated in the agreement; the architect's ordinary certification duties do not automatically grant independent audit authority. Shared savings also depends on an express clause, not the label CMc.

Apply the correct relationship

If a trade submits a proposal directly to an owner on a CMc project, route it through the contractual process involving the CMc. If several owner-held primes need a common schedule on a CMa project, coordinate through the CMa's agreed responsibilities. In both cases, identify who can authorize changes, verify the current document basis, and preserve the appropriate design review. Accurate relationship mapping is the prerequisite for accurate administration.

Reference: AIA B132 family and responsibilities.