Construction Manager at Risk Explained

Construction manager at risk (CMAR) is a project delivery method in which an owner hires a builder early as a paid preconstruction advisor, then converts that same firm into the contractor who guarantees a maximum price. The construction manager carries the cost risk above that number, while design and construction stay under two separate contracts.

For architects, this rearranges the usual sequence. Instead of finishing drawings and handing them to whoever bids lowest, you spend months across the table from the firm that will build the project. That changes how and when you draw.

What Is Construction Manager at Risk?

CMAR splits the builder's involvement into two stages under a single procurement. In the first, the CM prices the drawings, tests the schedule, flags long lead items, and warns which assemblies are getting expensive. The owner pays a fee, and the CM holds no construction liability yet.

In the second stage, the same firm signs an amendment and becomes the contractor. It hires subcontractors, holds the trade contracts and takes responsibility for delivering the building at or below an agreed ceiling. The phrase at risk means exactly this: cost above the ceiling comes out of the CM's pocket.

The owner still holds a direct contract with the architect, the structural difference from design-build. That independent line to the client matters when cost advice and design intent pull apart.

How the Construction Manager's Role Shifts Between Phases

Selection runs on qualifications and fee rather than lowest price, because nothing complete exists to price yet. The University of Missouri System facilities policy for CMAR uses a qualifications review, a shortlist of three to five firms, then proposals scored on experience, methodology, estimating capability and safety record.

The transition point is the moment advice becomes a guarantee. Weaker firms stay vague through preconstruction, then load that guarantee with qualifications once the owner has no alternative.

How the Guaranteed Maximum Price Is Built and Locked

A guaranteed maximum price is a stack, not one negotiated number: the estimated cost of the work, general conditions, the CM's fee and a contingency line. Federal rules in GSAM Subpart 536.71 on Construction-Manager-as-Constructor contracting define the GMP as the estimated cost of the work plus contingency plus fee, and require the final estimate before construction documents reach one hundred percent.

That timing is the part most students miss. The price is usually set between design development and roughly ninety percent construction documents, so the CM guarantees a building that is not fully drawn. Written assumptions and allowances bridge the gap, and those pages bind as tightly as the drawings.

The standard United States instrument is AIA Document A133, current edition A133–2019. Its GMP proposal becomes binding through a Guaranteed Maximum Price Amendment, and the form lets preconstruction and construction overlap for fast-tracking. AIA later issued A135–2024 as a collaborative variant, so confirm which form your project uses.

Contingency and Shared Savings

Two pots of money sit inside a CMAR budget, and confusing them causes most of the arguments. The construction manager's contingency lives inside the GMP and covers the CM's own risks: estimating gaps, coordination misses, subcontractor default. The owner's contingency sits outside the GMP and covers owner-driven scope changes.

Public owners fence that first pot carefully. The Missouri policy above requires owner approval before the CM draws on it and blocks its use for costs caused by the CM's own negligence. Without such language, contingency quietly becomes profit.

Savings sharing is the counterweight. If the job finishes below the GMP, the unspent balance is split by a formula in the contract, often between a full return to the owner and an even split. That discourages a padded estimate, though not every agreement includes one.

CM at Risk Compared With Other Delivery Methods

The closest relative is CM agency, and the two are constantly mixed up. An agency CM manages the process for the owner as a fiduciary and never holds trade contracts or guarantees a price. A CM at risk does both. Design-bid-build and design-build deserve their own comparison, so the table below is orientation only.

Delivery Methods at a Glance

Aspect	Design-Bid-Build	Design-Build	CM at Risk	CM Agency
Owner's contracts	Architect and contractor separately	One entity for design and construction	Architect and construction manager separately	Architect, CM adviser, each trade contractor
Builder joins at	After documents are complete	Before design begins	Early design, as a paid adviser	Early design, no build obligation
Price basis	Lump sum from competitive bids	Lump sum or GMP on criteria	Cost of work plus fee, capped by GMP	Fee for services only
Cost overrun risk	Contractor, within bid scope	Design-build entity	Construction manager, above the GMP	Owner
Common use	Simple, well-defined work	Speed-driven criteria-based projects	Complex buildings needing cost control	Owners with in-house capacity

Architects also ask how this differs from hiring a general contractor. During construction it barely does. The difference is everything before that: a general contractor prices a finished set it had no voice in producing, while a CM at risk is paid to influence the documents it will later be judged against.

What Changes for the Architect

Tempo changes first. Cost feedback arrives during design rather than after it, useful and uncomfortable in equal measure. A well-defined architecture design brief becomes the reference you return to when the CM proposes a cheaper assembly that quietly deletes something the client asked for.

Document sequencing changes next. Fast-tracking releases drawings in packages, so foundations get poured while the facade is still being detailed. Deciding which parts of the model carry enough information to bid is where a shared understanding of level of development in BIM ends arguments about readiness. Each package still needs to be a properly stamped and sealed set.

Fee structure changes last. Preconstruction meetings, package-by-package issues and repeated estimate reconciliations burn more hours than a single-issue set, so the arithmetic behind what an architect should charge needs adjusting before the contract is signed. Drawing standards for this work sit in our essentials for architects collection.

When CMAR Is the Right Fit

The method earns its keep where cost certainty matters more than lowest first price and the program is complex enough that buildability advice has value. Hospitals, laboratories, airports, university buildings and phased renovations of occupied facilities are the usual candidates. Renovation benefits most, since an early contractor can open walls and price what is there.

Public agencies use it heavily. Many United States states authorize CMAR by statute above a cost threshold, and the federal government adopted the equivalent construction manager as constructor method in 2019.

Read that audit as a caution, not a verdict. Cost increases negotiated with a single firm during design escape competitive pressure unless the owner checks the numbers. Once the CM is selected, competition has been traded for collaboration and must be replaced with scrutiny.

Small, fully documented projects are a poor fit, since preconstruction fees rarely return value on a straightforward warehouse. Thresholds and savings splits vary by region and owner, so treat published figures as starting points.

Misunderstandings Worth Correcting

Three ideas circulate that are simply wrong. CMAR does not remove competitive bidding, since trade packages are still bid and owners normally review those awards. The construction manager is not the owner's agent during construction, and the two sets of interests diverge the moment costs rise.

Early involvement also does not shift design liability onto the builder; the architect stays responsible for the sufficiency of the documents. What changes is the volume of documented advice you receive, which cuts both ways in a dispute. The Sydney Opera House construction saga shows how fast overlapping design and construction becomes an argument about who knew what.

What This Means for Your Next Project

Your Next Step: Ask for the GMP proposal's list of assumptions, clarifications and allowances on day one, and map each item against your drawings before the amendment is executed. That document explains most of the change orders you will see all year.

Frequently Asked Questions

Is a guaranteed maximum price the same as a fixed price?

No. A GMP caps a cost-reimbursable contract, so the owner pays actual costs plus fee up to the ceiling and keeps any unspent balance under the sharing formula. A fixed price is owed in full whatever the work costs, and a GMP ceiling adjusts for scope changes.

What is the difference between CM at risk and a general contractor?

During construction, very little: the CM holds subcontracts and runs the site the same way. The difference is preconstruction, where a construction manager at risk is hired and paid before the documents are finished, and helps shape the budget it will later guarantee.

When is the guaranteed maximum price usually locked?

Most often between design development and roughly ninety percent construction documents. Federal rules require the final estimate before documents reach one hundred percent, and the remaining gap is covered by written assumptions and allowances attached to the proposal.

Can the CMAR delivery method be used on public projects?

Yes, widely. Many United States states authorize it for public buildings above a cost threshold, university systems publish formal CMAR procurement policies, and the federal government adopted the equivalent method in 2019. Local statutes govern selection.