- What the Published Pass-Rate Data Actually Says
- Why a 0% Figure Is Not a Difficulty Rating
- What the ACAC Report Includes and Leaves Out
- What Really Sets the Bar: 75%, Angoff and 120 Questions
- Where Candidates Are Likely to Struggle: The Nine Domains
- The Eligibility Gate Before the Exam
- Exam-Day Mechanics That Affect Results
- Planning Around the Missing Data
- Retakes, Fees and the Cost of a Miss
- Frequently Asked Questions
- ACAC's 2025 exam pass ratio shows 0% from 0 passes in 1 examination, which is not a usable difficulty signal.
- The passing criterion is 75%, set by the certification board using modified Angoff, on 120 multiple-choice questions in three hours.
- ACAC's report includes retakes and state-licensing-only examinations, so it is not a clean first-attempt pass rate for certification.
- No domain weights or question allocations are published, so study all nine domains rather than guessing at emphasis.
What the Published Pass-Rate Data Actually Says
Candidates searching for a Council-certified Moisture Control Consultant pass rate usually want one number: what percentage of people pass on the first try. The honest answer is that the issuer has not published a number that answers that question. The American Council for Accredited Certification (ACAC), which administers the credential, released a 2025 exam pass ratio document showing a pass ratio of 0%, based on 0 passes out of 1 examination.
That is the entire dataset. One examination, zero passes. If you came here hoping for a headline such as "most candidates pass" or "most candidates fail," the public record supports neither claim. This article explains how to read that figure, what it does and does not cover, and how to prepare sensibly when the best available statistic cannot be used to estimate your odds. For a broader treatment of difficulty, see our complete CMCC difficulty guide, and for the canonical pass-rate summary, see CMCC Pass Rate 2026: What the Data Shows.
Why a 0% Figure Is Not a Difficulty Rating
A pass ratio is a fraction. When the denominator is one, the only possible outcomes are 0% and 100%. A single examination cannot establish typical difficulty, in the same way that one coin flip cannot establish whether a coin is fair. The 0% in ACAC's 2025 document describes one sitting in one calendar year. It tells you nothing reliable about the preparation level of that candidate, the quality of the question pool, or what a well-prepared consultant should expect.
Three practical conclusions follow:
- Do not treat 0% as evidence the exam is nearly impossible. The sample is far too small to support that reading.
- Do not treat it as evidence of anything favorable or unfavorable about retakes. The figure is a cohort snapshot, not a trend.
- Do not import numbers from other credentials. Pass rates quoted for similarly abbreviated certifications belong to different exams, different bodies and different candidate pools.
The right use of this statistic is as a caution against false precision. Any site that confidently quotes a specific CMCC pass percentage for this credential without citing ACAC's report is guessing.
What the ACAC Report Includes and Leaves Out
The report's scope matters as much as its size. According to the research behind this article, the ACAC pass-ratio report includes retakes and state-licensing-only examinations. That has two consequences for anyone trying to interpret it as a measure of certification difficulty.
| Question | What the 2025 ACAC report supports |
|---|---|
| How many examinations were counted? | 1 examination, with 0 passes |
| Does it isolate first attempts? | No. Retakes are included in the report's scope |
| Does it isolate the CMCC certification? | No. State-licensing-only examinations are also included |
| Does it show a multi-year trend? | No. It is a single dated cohort |
| Can it estimate your personal odds? | No |
Certification and licensing are separate uses of an examination. A licensing-only sitting may involve a different candidate population, different motivations and different preparation than someone pursuing the certification itself. Blending them in one ratio makes the number even less useful as a certification benchmark. The report does not give a first-attempt rate for certification candidates, and this article will not manufacture one.
What Really Sets the Bar: 75%, Angoff and 120 Questions
Since the pass rate cannot calibrate your effort, the exam's design can. The documented facts are concrete:
- Format: 120 multiple-choice questions, each with at least four answer choices.
- Time: three hours, closed book.
- Passing criterion: 75%, set by the certification board using a modified Angoff method.
- Delivery: testing center or online video-proctored, through testing provider Kryterion, Inc.
- Presentation: randomized question and answer order, with immediate results.
The modified Angoff method is a standard-setting technique in which subject-matter experts estimate how a minimally competent candidate would perform on each item. The practical meaning for you: the 75% line reflects a judgment about minimum professional competence rather than a curve against other test takers. Nobody is graded relative to the rest of the cohort, so the exam's difficulty is about your command of the content, not about how others performed. For the arithmetic of what 75% means on 120 items and how to plan around it, see CMCC Passing Score 2026.
Where Candidates Are Likely to Struggle: The Nine Domains
ACAC's dated examination chart lists nine domain lines, which are official examination objectives. The chart is unweighted, and no percentage weights or domain question allocations are published. Without weights you cannot responsibly skip a domain on the theory that it is lightly tested. The nine lines are below, with the kind of reasoning each one demands. For deeper treatment, see our complete guide to all nine content areas.
Domain 1: The Science of Water
The foundation for everything else. Expect to reason about how water moves and changes state, not only to recall definitions.
- Capillary action and why it lets moisture travel against gravity through porous materials
- How vapor, liquid and bound moisture behave differently in building materials
- Why material properties change diagnosis and drying approach
Domains 2 and 3: Site Drainage and Foundations
These domains connect exterior conditions to interior moisture problems.
- How grading, drainage and water management around a building influence what reaches the foundation
- How foundation type and condition affect moisture entry and how a consultant would diagnose it
Domains 4 and 5: Walls, Ceilings and Floors; Roofs and Building Envelope Assemblies
Building assemblies are where diagnosis gets difficult, because layers hide the source.
- How moisture moves through and accumulates within assemblies
- How envelope components interact, so that a symptom in one place can have a cause in another
Domains 6 and 7: Plumbing and HVAC
Mechanical systems are both moisture sources and moisture-control tools.
- Recognizing plumbing-related water sources and their typical patterns
- Understanding how HVAC operation affects humidity and moisture conditions
Domain 8: Structural Drying
The prescribed structural-drying text is a named handbook reference, so this domain rewards study of the source rather than summaries of it.
- Drying principles and how they connect back to the science of water
- Linking diagnosis to a drying plan rather than treating drying as a standalone procedure
Domain 9: Project Documentation
Consulting work lives or dies on its records, specifications and reports.
- What to document, why, and how documentation supports decisions and accountability
The scenario nature of the field means the strongest candidates connect domains rather than study them in isolation. A basement moisture complaint, for example, can touch water science, site drainage, the foundation, plumbing, HVAC and drying, and then end in a specification and a documented conclusion. Questions that bridge those links are harder to answer from rote memory.
A Known Grouping Difference You Should Understand
One source of confusion is worth flagging. ACAC's dated chart presents nine domain lines, including Plumbing and Project documentation as distinct items. The candidate handbook's CMCC section, in its current undated web edition, lists eight headings in total: seven technical headings plus the ACAC Code of Conduct. Its grouping differs from the chart and does not separately label Plumbing or Project documentation. No issuer statement resolving the difference was found, and neither source is claimed to supersede the other.
The sensible response is to study the union: cover all nine chart lines, and treat ethics under the ACAC Code of Conduct as additional required knowledge. That way you are covered whichever organization of the material the exam reflects. The CMCC study guide walks through how to reconcile the two.
The Eligibility Gate Before the Exam
Pass-rate discussions often ignore a structural fact: you cannot simply register and sit this exam. You first have to be accepted through a documented application. The eligibility routes are:
| Education background | Documented moisture-control consulting experience |
|---|---|
| High-school diploma or GED | Eight years |
| Qualifying four-year degree or equivalent, with 30 qualifying credits | Four years |
| Qualifying two-year degree or equivalent, with 15 qualifying credits | Six years |
Qualifying education is in relevant science, engineering, architecture, industrial hygiene or related fields. The application involves four project sheets, applicable transcripts and application verifications, followed by unanimous certification-board review. The handbook also requests employer affidavits, and applicants complete an electronic affidavit and required email verifications. Full details are in CMCC Requirements 2026.
This gate shapes the candidate pool. Everyone who reaches the exam has already documented years of field experience, which is one more reason a raw pass ratio from a handful of sittings says little about how a prepared, experienced consultant should expect to do.
Exam-Day Mechanics That Affect Results
Whether a candidate passes can depend on logistics as well as knowledge. Delivery is by testing center or online video proctoring. For the online option, candidates must supply:
- A computer
- An approved webcam
- A private location
- A continuous 2 Mbps upload and download connection
A connection or environment problem during a three-hour closed-book exam is an avoidable source of stress. Test your setup in advance, secure a genuinely private space, and know your delivery option before exam day. Immediate results mean you will learn the outcome at the end of the session. For scheduling considerations, see CMCC Exam Dates 2026.
Pacing is straightforward arithmetic: three hours for 120 questions averages 90 seconds per question. Scenario-style items that require connecting several domains may take longer, so build in a quick first pass and a review pass rather than lingering early.
Planning Around the Missing Data
When the statistics do not tell you how hard the exam is, plan against the known standard: 75% on 120 questions across nine unweighted domains. A useful way to sequence study is to schedule by dependency rather than by preference, since the science underlies everything else.
Water science and the exterior
- Domain 1 first, because capillary action and moisture behavior underpin later reasoning
- Domains 2 and 3 next, tracing how site drainage and foundations let water in
Assemblies and systems
- Domains 4 and 5 on walls, ceilings, floors, roofs and envelope assemblies
- Domains 6 and 7 on plumbing and HVAC as sources and as control tools
Drying, documentation and ethics
- Domain 8 with the prescribed structural-drying text and the EPA moisture-control guidance
- Domain 9 documentation practice, plus the ACAC Code of Conduct
The official handbook references are the ACAC Code of Conduct, the EPA's Moisture Control Guidance for Building Design, Construction and Maintenance (December 2013), and Ken Larsen et al., Leadership in Restorative Drying (fourth edition, 2014). One caution applies to the latter: ACAC links a public vendor page describing a 2014 Gold Edition, and equivalence with the handbook's fourth-edition label is not assumed, so verify which edition you are using. The handbook's selected review pages supplement the complete prescribed references and do not establish exhaustive exam coverage, so do not treat highlighted pages as the full syllabus.
Key Takeaway
Use practice questions to find gaps across all nine domains, then return to the official references to fix them. Practice material is only as good as its accuracy, so favor items that explain the reasoning. You can try domain-based questions on our CMCC practice test site.
A Caution About Unofficial Documents
User-uploaded "CMCC" materials circulate on document marketplaces, and a credential label does not establish relevant or accurate content. In our review of public previews, one CMCC-titled listing exposed moisture-science questions while another previewed financial statements and transaction analysis, which is clearly unrelated to this credential. Only previews were inspected, not full paid downloads or a validated question bank. Treat any unofficial source as unverified until you have checked it against the ACAC handbook and the prescribed references.
Retakes, Fees and the Cost of a Miss
Fees matter when you weigh the consequences of a failed attempt. For US and Canada, the initial fee is USD 500, made up of USD 100 for the examination plus USD 400 for certification for the first two-year term. The current official application quotes USD 525 outside the US and Canada. A retake costs USD 100. Course and book expenses are separate from issuer fees, and a prep course is optional. See CMCC Certification Cost 2026 for the full breakdown.
| Item | Amount |
|---|---|
| Initial fee (US/Canada) | USD 500 (USD 100 exam + USD 400 certification, first two-year term) |
| Official application quote outside US/Canada | USD 525 |
| Retake | USD 100 |
| Renewal (two-year term) | USD 400 and 40 RCs |
Once certified, the credential is valid for two years. Renewal requires USD 400 and 40 RCs, comprising 10 for continued field activity plus 30 professional-development hours under current procedures. Retain your records for audit. Whether the credential pays off depends on your role and market, and we separate evidence about moisture-consulting roles from any assumed certification premium in Is the CMCC Certification Worth It? and the salary guide.
Frequently Asked Questions
No 2026 pass rate has been published in the sources reviewed. ACAC's 2025 exam pass ratio shows 0% from 0 passes in 1 examination, which is too small a sample to indicate typical difficulty.
No. With only one examination counted, the figure cannot establish difficulty. It also includes retakes and state-licensing-only examinations, so it does not isolate first-attempt certification results.
The passing criterion is 75%, set by the certification board using modified Angoff. The exam has 120 multiple-choice questions, a three-hour limit, and is closed book. See the passing score guide for details.
No. ACAC's dated chart lists nine domain lines without percentage weights or question allocations, so plan to study every domain and treat ethics under the ACAC Code of Conduct as additional required knowledge.
A retake costs USD 100. Review your weakest domains against the official references and consider more scenario practice. Our study guide outlines a domain-by-domain approach to revising.