CMCC Exam Domains 2026: Complete Guide to All 9 Content Areas

What the Nine-Domain Chart Actually Is

The Council-certified Moisture Control Consultant (CMCC) credential is issued by the American Council for Accredited Certification (ACAC), and certification decisions are made by its CMCC Certification Board. The nine content areas in this guide come from an ACAC document titled CMCC and CMCI Examinations, approved March 6, 2024. Each domain line is an official examination objective.

Two limits matter before you plan anything. First, the chart is unweighted: ACAC publishes no percentage weights and no per-domain question allocations. Any site that tells you "Domain 4 is 18% of the exam" is inventing a number. Second, we are not asserting a named "2026 exam release." The domains below are the current published scope as of our research check, and you should confirm against ACAC's pages before you register.

Because the credential shares an acronym with unrelated uses (chiropractic colleges, climate research, medical settings and the similarly named Certified Moisture Control Contractor), make sure every resource you buy is about the ACAC consultant credential. If you are new to the basics, see What Is CMCC Certification? and What Does CMCC Stand For? first.

The Chart-Versus-Handbook Grouping Puzzle

Here is a wrinkle most prep sites skip. The ACAC CMCC Candidate Handbook (the current, undated web edition) lists eight headings: seven technical headings plus the ACAC Code of Conduct. Its grouping does not match the dated chart, and notably it does not separately label Plumbing or Project documentation. The chart, by contrast, lists nine distinct domain lines.

We found no ACAC statement that resolves the difference, and we do not claim the chart supersedes the handbook. The practical response is simple:

• Use the nine chart headings as your study checklist, because they are the finer-grained list.
• Read the handbook to see how ACAC groups the same material, and expect questions that cross your own mental boundaries.
• Keep Plumbing and Project documentation as explicit study blocks even though the handbook does not label them separately.
• Treat the ACAC Code of Conduct as additional required knowledge. It appears in the handbook's headings but is not one of the nine chart domain lines.

For a one-page recap once you have worked through all of this, the CMCC Cheat Sheet is a useful companion.

Domain 1: The Science of Water

Capillary action deserves special attention because it links directly to Domains 2 and 3. Water wicking up through a porous foundation material is a science question and a foundation question at the same time. When you study, always ask: what is the moisture source, how is it getting there, and what is pushing it?

Expect question stems that give you a symptom (staining, efflorescence, musty odor, a cold surface) and ask you to identify the most likely mechanism. Memorizing definitions is not enough; you need to reason from cause to effect.

Domains 2 and 3: Site Drainage and Foundations

These two domains are about stopping water before it reaches the building envelope's lowest and most vulnerable parts. Study them as a pair, because site conditions drive foundation behavior.

A classic scenario ties these together: a basement wall shows moisture damage, and the question asks for the most probable root cause. The strongest answers trace backward from the symptom through the foundation pathway to a site drainage problem, rather than treating only the interior surface.

Domains 4 and 5: Interior Assemblies and the Envelope

Domain 4: Walls, Ceilings and Floors

This domain covers how moisture behaves inside the layered assemblies of a building's interior and perimeter. Think about the materials in each assembly, their moisture tolerance, where water can be trapped, and how long a wet layer takes to dry once it is enclosed. Floors raise slab-moisture and subfloor questions; ceilings often reveal leaks that originated elsewhere; walls combine all the pathways at once.

Domain 5: Roofs and Building Envelope Assemblies

The envelope is the first line of defense against bulk water and a major regulator of vapor and air movement. Study how roof and wall assemblies shed water, how penetrations and transitions become leak points, and how air leakage can carry moisture into assemblies and create condensation concerns. The EPA moisture control guidance is especially relevant here, as it addresses moisture control across design, construction and maintenance.

Candidates who want a sense of how demanding this reasoning can feel should read How Hard Is the CMCC Exam? for a grounded view of difficulty.

Domains 6 and 7: Plumbing and HVAC

These are the two mechanical domains, and both are common sources of the moisture problems a consultant is hired to diagnose.

Differential diagnosis is the skill being tested. A damp ceiling could come from a roof leak, a plumbing line or HVAC condensation. Strong candidates learn the telltale differences and the clarifying questions that separate them.

Domains 8 and 9: Structural Drying and Project Documentation

Domain 8: Structural Drying

This is where diagnosis becomes action. Structural drying covers the principles and practice of removing moisture from building materials and the environment in a controlled way, monitoring progress, and knowing when drying is complete. The handbook's prescribed reference here is Ken Larsen et al., Leadership in Restorative Drying, fourth edition (2014). A public vendor page describes that title as a 2014 Gold Edition, and we do not assume the two labels are equivalent, so confirm the exact edition ACAC expects before you purchase.

If you are searching for a focused resource, the CMCC Study Guide covers how to approach the structural-drying text alongside the other references.

Domain 9: Project Documentation

Documentation is easy to undervalue and costly to ignore. A consultant's findings are only as useful as the record behind them. Study what a defensible project record contains: observations, measurements, conditions found, assumptions, the rationale for recommendations and the progress of any drying work. Like Plumbing, Project documentation is not separately labeled in the handbook, so schedule it deliberately.

Building a Reading Map Around the Official References

ACAC's handbook points to three references, and your study plan should be anchored to them rather than to third-party summaries:

1. ACAC Code of Conduct (available at acac.org/conduct), which covers the ethics knowledge treated as additional required material.
2. EPA Moisture Control Guidance for Building Design, Construction and Maintenance (December 2013), a public document that maps well onto Domains 1 through 5 and 7.
3. Ken Larsen et al., Leadership in Restorative Drying, fourth edition (2014), the anchor for Domain 8 and related drying concepts.

One honest caveat: the handbook's selected review pages supplement the complete prescribed references and do not establish exhaustive exam coverage. Reading only highlighted pages is a risk. Read the full documents.

Sequencing the Domains Across Your Prep

You do not need a generic study system; you need a sequence that respects how the domains depend on each other. Here is one example arc you can stretch or compress. It is not a published ACAC schedule.

The logic is simple: science first, then where water enters, then what it damages, then how it is removed and recorded. You can try mixed-domain questions on our CMCC practice test site as you go.

Exam Format, Fees and Delivery

Knowing the mechanics keeps logistics from becoming a distraction on exam day.

• Format: 120 multiple-choice questions, each with at least four answer choices, over three hours. The exam is closed book, with randomized question and answer order and immediate results.
• Passing criterion: 75%, set by the certification board using a modified Angoff method. See CMCC Passing Score for more.
• Delivery: Kryterion, Inc. administers the exam, through a testing center or online video proctoring.
• Online requirements: a computer, an approved webcam, a private location and a continuous 2 Mbps upload and download connection.
• Fees: initial US/Canada fee of USD 500 (USD 100 examination plus USD 400 certification for the first two-year term); the current application quotes USD 525 outside the US/Canada. A retake is USD 100. Course and book expenses are separate from issuer fees. For the full picture see CMCC Certification Cost.

Eligibility is experience-based and has three routes: a high-school diploma or GED plus eight years of documented moisture-control consulting experience; a qualifying four-year degree or equivalent (30 qualifying credits) plus four years; or a qualifying two-year degree or equivalent (15 qualifying credits) plus six years. Applications include four project sheets, transcripts and verifications, followed by unanimous certification-board review. Note that the application page and handbook conflict on some details (six months with online verification versus 90 days with notarized instructions; board meeting cadence), so confirm current instructions with ACAC. Details are in CMCC Requirements.

Certification lasts two years. Renewal costs USD 400 and requires 40 RCs: 10 for continued field activity plus 30 professional-development hours under current procedures. Keep your records, because they may be audited.

Frequently Asked Questions

For hands-on repetition across all nine areas, head to the CMCC Exam Prep practice questions and work scenarios that connect the science, the building systems, the drying response and the documentation.