Download Nevada — C-17 Lathing / Plastering Contractor Actual Exam Newest Questions with Answers and more Exams Construction in PDF only on Docsity!
Nevada — C-17 Lathing / Plastering
Contractor Actual Exam Newest
Questions with Answers & Rationales
1. What is the primary purpose of lathing? A. Decorative design only B. Structural support for ceilings C. Provide a base for plaster application D. Insulation Correct Answer: C Rationale: Lath supports the plaster and ensures adhesion to walls and ceilings. 2. Which material is commonly used for metal lath? A. Aluminum foil B. Galvanized steel C. Wood veneer D. Plastic Correct Answer: B Rationale: Galvanized steel resists rust and provides a strong base for plaster. 3. Which plaster type is best for exterior applications? A. Gypsum plaster B. Clay plaster C. Portland cement plaster D. Lime plaster
Correct Answer: C Rationale: Cement plaster withstands moisture and weather conditions.
4. What is the purpose of scratch coat in plastering? A. Final finish layer B. First coat to provide keying for subsequent layers C. Decorative coating D. Insulation Correct Answer: B Rationale: Creates a rough surface for better adhesion of brown and finish coats. 5. Which tool is used to apply and smooth plaster? A. Hammer B. Hawk and trowel C. Paint roller D. Sander Correct Answer: B Rationale: Hawk holds plaster while the trowel spreads it evenly. 6. Which factor affects plaster curing? A. Color of lath B. Temperature and humidity C. Type of paint D. Wall thickness only Correct Answer: B Rationale: Environmental conditions influence setting time and strength. 7. Which defect is caused by applying plaster too thickly at once? A. Smooth finish B. Cracking or sagging
A. Smooth finish B. Cracking or crazing C. Increased adhesion D. Enhanced color Correct Answer: B Rationale: Rapid drying in some areas causes cracks.
12. Which type of plaster is most fire-resistant? A. Gypsum plaster B. Portland cement plaster C. Clay plaster D. Oil-based plaster Correct Answer: B Rationale: Cement plaster withstands higher temperatures without burning. 13. What is the purpose of brown coat? A. Final decorative coat B. Intermediate layer to level surface C. Primer for paint D. Waterproofing Correct Answer: B Rationale: Brown coat evens the surface and prepares for finish coat. 14. Which safety equipment is essential when mixing plaster? A. Gloves, dust mask, and safety glasses B. Hard hat only C. Ear plugs only D. Steel-toe boots only Correct Answer: A Rationale: Prevents skin irritation, dust inhalation, and eye injuries.
15. Which tool measures wall straightness before plastering? A. Trowel B. Plumb line or level C. Sander D. Hammer Correct Answer: B Rationale: Ensures walls are straight for a uniform plaster finish. 16. What is the recommended lath spacing for metal lath? A. Close or specified by manufacturer B. Random C. One inch apart only D. Continuous without spacing Correct Answer: A Rationale: Correct spacing ensures proper plaster keying and strength. 17. Which plastering defect is caused by applying finish over dusty surfaces? A. Smooth surface B. Poor adhesion and peeling C. Increased strength D. Uniform sheen Correct Answer: B Rationale: Dust prevents bonding between plaster and underlying coat. 18. Which method ensures proper plaster thickness? A. Applying thick coats at once B. Using scratch, brown, and finish coats sequentially C. Single coat only D. Skipping brown coat
C. Applying thick coats D. Ignoring environmental conditions Correct Answer: B Rationale: Slow, even curing prevents shrinkage cracks.
23. Which tool is used to score the scratch coat? A. Brush B. Roller C. Notched trowel or comb D. Sander Correct Answer: C Rationale: Scoring creates mechanical keying for the brown coat. 24. Which plaster defect results from insufficient lath fastening? A. Smooth wall B. Plaster detachment or sagging C. Improved adhesion D. Enhanced durability Correct Answer: B Rationale: Loose lath cannot support the plaster, causing failure. 25. Which material improves adhesion of plaster on masonry walls? A. Paint B. Bonding agent or cement slurry C. Wax D. Plastic sheet Correct Answer: B Rationale: Bonding agents increase mechanical and chemical adhesion. 26. Which tool removes high spots after brown coat application?
A. Hammer B. Straightedge and darby C. Trowel only D. Roller Correct Answer: B Rationale: Levels surface for a smooth finish coat.
27. Which factor most affects plaster drying time? A. Lath type only B. Temperature, humidity, and coat thickness C. Color of plaster D. Room size Correct Answer: B Rationale: Environmental conditions and thickness determine set and cure time. 28. Which plaster type is resistant to moisture and ideal for bathrooms? A. Gypsum plaster B. Portland cement plaster C. Clay plaster D. Oil-based plaster Correct Answer: B Rationale: Cement plaster withstands humidity without softening. 29. Which safety precaution prevents eye injury when cutting lath? A. Gloves only B. Safety glasses C. Dust mask only D. Steel-toe boots only
C. Finish coat (or skim coat) D. Base coat only Correct Answer: C Rationale: Finish coat provides aesthetic appearance and uniform texture.
34. Which method improves plaster adhesion to gypsum board? A. Painting first B. Applying bonding primer or mesh tape at joints C. Using wax D. Adding extra coats Correct Answer: B Rationale: Bonding primer and tape reinforce adhesion at seams. 35. Which safety hazard is common when mixing dry plaster? A. Falling B. Dust inhalation C. Electrical shock D. Slipping Correct Answer: B Rationale: Plaster dust can irritate lungs, eyes, and skin. 36. Which material can be used to reinforce plaster in curved surfaces? A. Wood only B. Wire mesh C. Cement only D. Plastic sheets Correct Answer: B Rationale: Wire mesh supports plaster on arches or curved walls. 37. Which defect occurs if plaster is applied too quickly?
A. Smooth finish B. Cracking or sagging C. Improved adhesion D. Uniform texture Correct Answer: B Rationale: Quick application can trap air and cause weak areas.
38. Which tool checks the smoothness of the finish coat? A. Level or straightedge B. Trowel only C. Hawk D. Brush Correct Answer: A Rationale: Straightedges detect high and low spots for corrective sanding. 39. Which plastering step protects corners and edges? A. Brown coat only B. Scratch coat only C. Corner beads installation D. Finish coat only Correct Answer: C Rationale: Corner beads create durable and sharp edges. 40. Which material prevents plaster cracking over joints? A. Plastic sheet B. Paint C. Reinforcing mesh or tape D. Wax Correct Answer: C Rationale: Mesh distributes stress and prevents cracks. 41. Which factor contributes most to plaster shrinkage cracks?
45. Which type of plaster sets the fastest? A. Gypsum plaster B. Fast-setting gypsum or hydraulic plaster C. Clay plaster D. Cement plaster Correct Answer: B Rationale: Special gypsum plasters set quickly for rapid finishing. 46. Which tool shapes plaster edges around openings? A. Brush B. Roller C. Trowel or corner tool D. Level Correct Answer: C Rationale: Tools create neat edges around windows and doors. 47. Which defect occurs when scratch coat is too thin? A. Smooth finish B. Poor keying for brown coat C. Enhanced adhesion D. Uniform appearance Correct Answer: B Rationale: Insufficient scratch coat prevents mechanical bond of subsequent layers. 48. Which material prevents rust stains on plaster? A. Plastic sheet B. Paint C. Galvanized or stainless steel lath D. Wax Correct Answer: C Rationale: Metal lath coating prevents oxidation and staining.
49. Which type of plaster is easy to sand after setting? A. Cement plaster B. Gypsum plaster C. Oil-based plaster D. Clay plaster Correct Answer: B Rationale: Gypsum sets smooth and can be sanded for final finishing. 50. Which method ensures durability of plaster walls? A. Skip bonding agent B. Apply thick coats only C. Proper lath installation, layering, and curing D. Rapid drying Correct Answer: C Rationale: Durable plaster requires proper support, layering, and controlled curing. 51. Which factor can cause plaster to sag on ceilings? A. Thin coat B. Excessive thickness or wet plaster C. Smooth lath D. Proper ventilation Correct Answer: B Rationale: Plaster applied too thickly can pull away from the lath and sag under its weight. 52. Which defect results from applying plaster on a damp surface? A. Smooth finish B. Blistering or peeling C. Enhanced adhesion D. Uniform color
A. Smooth surface B. Cracking or crazing C. Increased adhesion D. Enhanced shine Correct Answer: B Rationale: Rapid drying in some areas leads to stress and hairline cracks.
57. Which plaster type is ideal for soundproofing? A. Gypsum plaster B. Lime or gypsum-based acoustic plaster C. Cement plaster D. Oil-based plaster Correct Answer: B Rationale: Special acoustic plasters reduce sound transmission in walls and ceilings. 58. Which safety hazard is associated with cutting metal lath? A. Dust inhalation only B. Cuts and eye injuries from sharp edges C. Hearing damage D. Chemical burns Correct Answer: B Rationale: Metal lath edges are sharp; gloves and safety glasses are essential. 59. Which coat provides the final decorative texture? A. Scratch coat B. Brown coat C. Finish coat (or skim coat) D. Base coat only
Correct Answer: C Rationale: Finish coat is smooth and ready for painting or texturing.
60. Which method prevents plaster cracks over joints in lath? A. Thick coat application B. Skipping scratch coat C. Use of reinforcing mesh or tape D. Rapid drying Correct Answer: C Rationale: Mesh distributes stress and prevents crack formation at weak points. 61. Which defect is caused by insufficient lath fastening? A. Smooth wall B. Plaster sagging or detachment C. Uniform sheen D. Enhanced durability Correct Answer: B Rationale: Loose lath cannot support plaster, leading to failure over time. 62. Which factor most affects plaster curing time? A. Color of plaster B. Temperature, humidity, and coat thickness C. Type of lath only D. Room size Correct Answer: B Rationale: Environmental conditions influence set time and strength development. 63. Which plastering tool is used to create grooves in scratch coat?
67. Which defect occurs if plaster is applied too thickly in one coat? A. Smooth wall B. Sagging or cracking C. Improved adhesion D. Enhanced sheen Correct Answer: B Rationale: Excess thickness creates stress that leads to failure. 68. Which plaster type is most resistant to fire? A. Oil-based plaster B. Gypsum plaster C. Portland cement plaster D. Clay plaster Correct Answer: C Rationale: Cement plaster withstands high temperatures without burning. 69. Which material prevents rust stains from metal lath? A. Wax B. Galvanized or stainless steel lath C. Plastic sheet D. Paint Correct Answer: B Rationale: Metal coatings prevent oxidation and unsightly rust marks. 70. Which coat is used to level walls before finish coat? A. Scratch coat B. Brown coat C. Finish coat D. Base coat only
Correct Answer: B Rationale: Brown coat ensures an even, smooth surface for the final finish.
71. Which tool smooths and polishes the finish coat? A. Notched trowel B. Hawk C. Trowel or float D. Brush Correct Answer: C Rationale: Troweling produces a uniform, polished surface. 72. Which method ensures durability of exterior plaster? A. Skip scratch coat B. Proper lath installation, layering, and curing C. Apply thick coat once D. Rapid drying with heat Correct Answer: B Rationale: Layering and proper curing increase longevity and resistance to weather. 73. Which safety precaution prevents inhalation of plaster dust? A. Gloves only B. Dust mask or respirator C. Steel-toe boots only D. Hard hat only Correct Answer: B Rationale: Respirators prevent lung irritation from airborne particles. 74. Which method prevents cracking in finish coat? A. Thick single coat B. Multiple thin coats with proper curing
