10 exam-style questions with answers and explanations, straight from our 1,030-question bank. Tap an answer to check yourself. When you're ready, take the scored version in the free practice test.
These 10 free MFBA questions are organized by exam domain, so you can see how each part of the Multifamily Building Analyst blueprint is tested. Reveal the answer and explanation under each question.
Domain 1: Building Science
Question 1
On a calm winter morning, an eight-story building is warmer indoors than outdoors. Pressure measurements relative to outdoors are negative on the lowest floors, near zero around the fourth floor, and positive on the highest floors. Similar readings remain when the ventilation fans are briefly turned off under an approved test procedure. Which explanation accounts for the change in pressure with height?
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Correct answer: A - Stack effect in vertically connected spaces, with a neutral pressure level near the fourth floor.
Question 2
For a simplified whole-wall model, 75% of the opaque wall area has a complete heat-flow path of R-24 and the remaining 25% has a complete framing path of R-6. Both path values already include the surface films and continuous layers. Treat the paths as parallel and neglect lateral heat flow. An analyst has entered R-19.5 by area-weighting the two R-values. Which replacement input correctly represents this assembly?
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Correct answer: B - R-13.7, calculated from the conductance of each path and its area fraction.
Domain 2: Auditing Skills
Question 3
A resident tells the auditor, "Management says we waste heat by opening windows, but the bedroom is unbearable at night." The superintendent previously reported that residents leave windows open even when the building is cold. Which reply obtains useful evidence without accepting either person's explanation prematurely?
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Correct answer: D - "That sounds uncomfortable. When does the bedroom overheat, and what happens in the other rooms?"
Question 4
A common-area lighting proposal replaces 100 fixtures drawing 60 W each, including ballast losses, with 24 W LED fixtures. Existing operation is 4,000 hours per year. Occupancy controls will reduce the new fixtures' operation to 2,500 hours per year, with no dimmed standby mode and negligible control power. Required illumination and emergency lighting are preserved. What annual lighting electricity reduction belongs in the combined proposal?
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Correct answer: C - 18,000 kWh.
Domain 3: Inspection and Diagnostic Skills
Question 5
A central rooftop fan serves the bathroom exhaust riser in a six-story apartment building. A calibrated, pressure-compensated flow hood measures 18 cfm at one apartment's grille with its windows and entrance door closed. Opening a living-room window raises the grille flow to 51 cfm; closing it returns the flow to 18 cfm. Fan speed and branch settings remain unchanged. The design flow is 50 cfm. These findings point most strongly to:
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Correct answer: C - An inadequate replacement-air path into the apartment.
Question 6
An apartment blower-door test requires 720 cfm to maintain the apartment at 50 Pa below outdoors. During a second test, every adjoining conditioned space is also held at 50 Pa below outdoors, while the apartment remains at the same outdoor pressure difference. Its fan now requires 290 cfm. No sealing or other physical changes have been made. What does the lower guarded-test flow demonstrate?
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Correct answer: D - The initial measurement combined exterior leakage with leakage to other conditioned spaces.
Question 7
Dark staining recurs at the exposed edge of a concrete balcony slab inside a fifth-floor apartment. During a cold, dry week, room air has a measured dew point of 48°F. The stained surface is 41°F, while adjacent wall surfaces are 65°F. The staining does not track rain or plumbing use, and no wet materials are found above the location. Which mechanism best fits this pattern?
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Correct answer: B - Room moisture condensing on the thermally bridged slab edge.
Domain 4: Installation and Analysis Skills
Question 8
Two 12-month periods for a fully occupied apartment building show 24,000 therm of gas use before an envelope retrofit and 19,200 therm afterward. The corresponding heating degree days, calculated at the same base temperature, are 6,000 and 4,800. Separate analysis establishes an unchanged nonheating baseload of 4,800 therm per year. Heating use is proportional to degree days; other operating conditions are unchanged. At the pre-retrofit year's weather, the annual gas savings attributable to the retrofit are:
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Correct answer: B - 1,200 therm.
Question 9
A gas-use model matches an apartment building's annual bill total within 1%. Month by month, however, it overpredicts summer gas use and underpredicts winter gas use. The same utility meter serves space heating and domestic hot water. Billing dates, weather data, and occupancy have been verified. The annual agreement is best understood as:
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Correct answer: A - Compensating errors: excess modeled baseload offsets too little modeled heating consumption in the annual total.
Domain 5: Health and Safety
Question 10
During an apartment visit, a functioning personal CO monitor shows 62 ppm and continues rising. A resident reports headache and nausea. The household CO alarm is silent, and the combustion source has not been located. Before tracing the source, the auditor should:
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Correct answer: D - Move everyone outside to fresh air, then call 911 and request emergency assistance.
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The full bank has 1,020 more MFBA questions with explanations.