NCCER Interior Finishing & Drywall 2 — Questions and Answers
Question 1: What is the first coat of joint compound applied during drywall finishing called?
- Finish coat
- Skim coat
- Tape coat (embedding coat) (Correct answer)
- Texture coat
Correct answer: Tape coat (embedding coat)
The tape coat, also called the embedding coat, is the first application and is used to embed paper tape into the wet compound over joints.
Question 2: How many total coats of joint compound are typically required to achieve a professional-quality finish?
- 1 coat
- 2 coats
- 3 coats (Correct answer)
- 4 coats
Correct answer: 3 coats
Three coats are the professional standard: the tape coat, a filler coat, and a finish coat, each applied only after the previous coat has fully dried.
Question 3: What type of drywall tape is most appropriate for finishing inside corners?
- Fiberglass mesh tape
- Paper tape (Correct answer)
- Metal corner bead
- Vinyl corner tape
Correct answer: Paper tape
Paper tape is preferred for inside corners because it can be creased along its center crease and feathered smoothly into both adjoining surfaces.
Question 4: What is the primary purpose of metal or vinyl corner bead on outside drywall corners?
- To seal the corner joint against moisture infiltration
- To protect the corner from impact damage and provide a straight finishing edge (Correct answer)
- To increase fire resistance at exterior corners
- To add decorative detail to wall corners
Correct answer: To protect the corner from impact damage and provide a straight finishing edge
Corner bead protects vulnerable outside corners from dents and chips while giving finishers a consistent straight edge to feather compound against.
Question 5: In drywall finishing, what does the technique called 'feathering' mean?
- Applying a thick, even coat across the entire joint
- Thinning the compound edges so they blend imperceptibly into the surrounding wall (Correct answer)
- Using a specialized feather brush to create wall texture
- Mixing compound with water until it reaches a thin, pourable consistency
Correct answer: Thinning the compound edges so they blend imperceptibly into the surrounding wall
Feathering means gradually tapering the edges of each compound coat outward so the transition from joint to wall surface becomes invisible.
Question 6: What is the proper preparation step between drywall compound coats?
- Add water to thin the compound for easier spreading
- Mix in a hardener to accelerate drying
- Lightly sand the dried coat and wipe away all dust (Correct answer)
- Apply a primer to seal the previous coat
Correct answer: Lightly sand the dried coat and wipe away all dust
Lightly sanding the dried previous coat and removing the dust ensures proper adhesion and allows the next coat to go on smoothly.
Question 7: Which type of joint compound is best suited for the final finish coat?
- All-purpose compound
- Lightweight topping compound (Correct answer)
- Setting-type compound (hot mud)
- Base coat compound
Correct answer: Lightweight topping compound
Lightweight topping compound is formulated for finish coats because it spreads thinly, shrinks minimally, and sands to a smooth surface with little effort.
NCCER Interior Finishing & Drywall 2
What is the first coat of joint compound applied during drywall finishing called?