Free NCCER Drywall Mechanic knowledge assessment Practice Questions

Sample Practice Questions

Try these 10 sample questions from the NCCER Drywall Mechanic knowledge assessment practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1A drywall crew is setting up a standard supported scaffold platform. What is the minimum required platform width if no narrow-area or scaffold-type exception applies?

   1. A. 12 inches
   2. B. 14 inches
   3. C. 18 inches
   4. D. 24 inches

   Answer: C

   Explanation: OSHA states, "Except as provided in paragraphs (b)(2)(i) and (b)(2)(ii) of this section, each scaffold platform and walkway shall be at least 18 inches (46 cm) wide." The standard platform therefore needs at least 18 inches of width.

   Reference: OSHA 29 CFR 1926.451, General Requirements for Scaffolds — 1926.451(b)(2)

2. 2A rectangular wall to be covered with gypsum board is 12 feet long and 9 feet high. What is its gross area?

   1. A. 42 square feet
   2. B. 108 square feet
   3. C. 96 square feet
   4. D. 21 square feet

   Answer: B

   Explanation: NIST gives the rectangular area rule as "length × width". Multiplying 12 feet by 9 feet gives 108 square feet.

   Reference: NIST Circumference, Area and Volume — Calculate Circumference, Area and Volume; Area of rectangle

3. 3A pneumatic hose used with metal-framing tools has an inside diameter above the OSHA trigger size. Above what inside diameter must a safety device be installed at the supply or branch line to reduce pressure if the hose fails?

   1. A. 3/8 inch
   2. B. 1/2 inch
   3. C. 5/8 inch
   4. D. 3/4 inch

   Answer: B

   Explanation: OSHA states, "All hoses exceeding 1⁄2-inch inside diameter shall have a safety device at the source of supply or branch line to reduce pressure in case of hose failure." The trigger boundary is one-half inch.

   Reference: OSHA 29 CFR 1926.302, Power-Operated Hand Tools — 1926.302(b)(7)

4. 4A batt must fit around a service line in a framed wall. Which fitting method best maintains insulation continuity under the ENERGY STAR guidance?

   1. A. Split and fit the batt around the line without compression
   2. B. Notch and compress the batt tightly behind the service line
   3. C. Run a full batt ahead of the line, leaving a rear cavity void
   4. D. Stop the batt at the line and seal the facing over the opening

   Answer: A

   Explanation: ENERGY STAR calls for placement that will "eliminate gaps, voids, and compression". Splitting and fitting the batt around the line preserves continuity without compression.

   Reference: ENERGY STAR Complete Thermal Enclosure System — Properly Installed Insulation

5. 5On a nonrated wood-stud wall, a mechanic is attaching gypsum board with nails. Under the cited installation guide, what is the maximum spacing for nails along each framing member?

   1. A. 7 inches on center
   2. B. 8 inches on center
   3. C. 12 inches on center
   4. D. 16 inches on center

   Answer: B

   Explanation: The Georgia-Pacific guide states, "Nails should be spaced not more than 8” (203 mm) o.c. along framing members." Thus the guide's maximum wall-nail spacing is 8 inches.

   Reference: Georgia-Pacific ToughRock Gypsum Products Technical Guide — page 4, Interior Gypsum Board Installation, Walls

6. 6A drywall finisher is preparing to apply ready-mix joint compound. Under the cited guide, what minimum temperature must be maintained continuously before and during finishing until the material dries?

   1. A. 40°F for 24 hours before finishing
   2. B. 50°F for 48 hours before finishing
   3. C. 60°F for 24 hours before finishing
   4. D. 70°F for 48 hours before finishing

   Answer: B

   Explanation: The ProForm guide states, "A minimum temperature of 50˚F (10˚C) should be maintained continuously for 48 hours prior to and throughout the finishing process until applied materials are thoroughly dry." The 50°F and 48-hour combination applies.

   Reference: National Gypsum ProForm Finishing Products Construction Guide — page 16, Installation Guide, Environmental Conditions

7. 7A drywall mechanic needs the horizontal location of door openings along a partition before laying out studs. Which drawing view is the direct source for that horizontal placement?

   1. A. Floor plan
   2. B. Exterior elevation
   3. C. Wall section
   4. D. Isometric view

   Answer: A

   Explanation: The Army construction-drawing guide says, "Horizontal dimensions appear in plan views" and that plan dimension strings show "the placement of openings such as doors, windows, and louvers." A floor plan supplies the needed horizontal placement.

   Reference: U.S. Army TM 5-304 Construction Drawings Guide — Appendix F, F-2(c), Floor Plans

8. 8A suspended acoustical ceiling will be installed below exposed bar joists. How should the main beams run relative to those joists in the installation guide?

   1. A. Parallel to the joists
   2. B. Perpendicular to the joists
   3. C. Diagonally across the joists
   4. D. Aligned with cross tees

   Answer: B

   Explanation: The guide says, "In spaces with bar or wood joists, main beams must be oriented perpendicular to the joists." That orientation applies to the exposed bar joists.

   Reference: Installing Suspended Ceilings: Assembly and Installation Instructions — Determine Panel Direction

9. 9A designer specifies molded, thin-shell, nonloadbearing ornamental coves for an interior lobby. Which specialty product fits this work?

   1. A. Fabric-covered panel
   2. B. Wood veneer panel
   3. C. Glass fiber reinforced gypsum part
   4. D. Solid-vinyl wallcovering

   Answer: C

   Explanation: ASTM describes molded glass fiber reinforced gypsum as "nonload-bearing, thin-shell, ornamental shapes for architectural embellishment of interior building construction." That description identifies the specified GFRG part.

   Reference: ASTM C1381/C1381M-23 Standard Specification for Molded Glass Fiber Reinforced Gypsum Parts — Scope 1.1

10. 10A crew is preparing a wall for EIFS with Drainage under ANSI/EIMA 99A-2017. Which system layer goes over the substrate before insulation board is attached?

    1. A. Finish coat
    2. B. Reinforcing mesh
    3. C. Water-resistive barrier
    4. D. Base coat

    Answer: C

    Explanation: The standard says, "A water-resistive barrier that complies with the applicable building code shall be installed over the substrate." That is the layer over the prepared substrate in this drainage assembly.

    Reference: ANSI/EIMA 99A-2017 Standard for Exterior Insulation and Finish Systems and EIFS with Drainage — Section 14.3.3(a), EIF Systems with Drainage