Nevada C-20 Tiling Contractor Exam | Practice
Questions And Answers 2026/2027 | Complete
Questions And Answers (Verified Answers) | Exam Prep
Comprehensive Exam Guide 2026&2027
1. Under Nevada's C-20 Tiling classification, which activity is generally within the scope of
the classification?
A. Installing structural concrete walls
B. Installing ceramic and other qualifying tile products using adhesives or suction
C. Installing structural steel framing
D. Installing complete plumbing systems
Answer: B
The C-20 classification covers the installation of ceramic, encaustic, vitreous, and other tile-
like products, subject to the classification's limitations.
2. A tile contractor is preparing a bathroom floor over a concrete slab. Before beginning
the installation, what should be evaluated first?
A. Surface condition and suitability for the planned tile system
B. Color of the customer's cabinets
C. Contractor vehicle capacity
D. Final cleaning schedule only
Answer: A
A suitable substrate is fundamental to a durable tile installation. Cracks, contamination,
moisture, flatness, and other substrate conditions should be evaluated before installation.
3. A contractor notices that a concrete substrate has significant dust and loose material
immediately before applying tile adhesive. What is the most appropriate action?
A. Increase adhesive thickness to compensate
B. Install tile and rely on grout to stabilize it
C. Clean and properly prepare the substrate before installation
D. Add additional water to the adhesive
Answer: C
Bonding materials require a properly prepared substrate. Dust and loose material can
interfere with adhesion and contribute to tile failure.
,4. Which condition presents the greatest immediate concern before setting large-format
tile?
A. Tile color variation
B. Customer-selected grout color
C. Packaging design
D. Significant substrate unevenness
Answer: D
Large-format tile is particularly sensitive to substrate flatness. Excessive unevenness can
create lippage, poor coverage, and bonding problems.
5. During a layout inspection, the installer discovers that the final row of tile would be only
1/2 inch wide. What is generally the best approach?
A. Proceed because narrow cuts are always acceptable
B. Adjust the layout so cuts are balanced and visually appropriate
C. Eliminate the final row
D. Increase grout-joint width dramatically
Answer: B
A properly planned layout avoids undesirable sliver cuts and creates a balanced appearance
while maintaining appropriate joint dimensions.
6. Why are movement joints important in tiled installations?
A. They allow controlled movement and help reduce stress-related cracking
B. They eliminate the need for substrate preparation
C. They replace all grout joints
D. They make tile waterproof by themselves
Answer: A
Movement accommodation is necessary because assemblies can expand, contract, and shift.
Properly placed movement joints help prevent excessive stress from being transferred to tile
and grout.
7. A homeowner asks the contractor to install tile directly over a surface that is visibly
contaminated with oil. What should the contractor do?
A. Use thicker grout
B. Apply more tile sealer
C. Ignore the contamination
D. Correctly clean and prepare the surface before installation
,Answer: D
Oil and similar contaminants can interfere with bonding. Proper surface preparation must
precede installation.
8. Which tool is most directly useful for checking whether a tile installation is maintaining a
consistent plane?
A. Tape measure
B. Chalk line
C. Straightedge
D. Utility knife
Answer: C
A straightedge can reveal deviations in the tile plane and help identify lippage or substrate
irregularities.
9. When mixing a cement-based tile-setting material, why should the manufacturer's
specified water ratio be followed?
A. It determines only the final color
B. It helps achieve the intended working and performance characteristics
C. It eliminates curing requirements
D. It guarantees that substrate preparation is unnecessary
Answer: B
Incorrect water content can adversely affect workability, strength, bond performance, and
curing characteristics.
10. A tile installer adds substantial extra water to a setting material because it has become
difficult to spread. What is the principal concern?
A. The tile will become heavier
B. The grout joints will automatically widen
C. The material may no longer perform as designed
D. The tile will become waterproof
Answer: C
Adding water beyond the manufacturer's requirements can alter the material's designed
properties and compromise performance.
11. What is the primary purpose of a notched trowel when applying tile-setting material?
, A. To create consistent ridges that can provide appropriate coverage when the tile is embedded
B. To cut ceramic tile
C. To polish grout
D. To remove cured adhesive
Answer: A
The notched profile helps distribute setting material consistently and supports appropriate
contact between tile and substrate.
12. A tile installer discovers that a trowel is producing inconsistent ridges because several
teeth are worn. What should be done?
A. Add more water to the setting material
B. Continue because trowel condition has no effect
C. Replace or properly repair the unsuitable trowel
D. Increase grout-joint width
Answer: C
Consistent trowel ridges contribute to predictable coverage. A damaged or worn trowel can
produce inconsistent application.
13. During installation, a contractor notices insufficient setting-material coverage beneath a
tile. What is the most appropriate response?
A. Continue and fill the perimeter with grout
B. Improve the application technique and verify coverage requirements
C. Reduce substrate preparation
D. Seal the tile immediately
Answer: B
Adequate contact between tile and setting material is essential for bond and performance,
particularly in demanding installations.
14. Which condition can contribute to cracked tile after installation?
A. Properly planned movement accommodation
B. Correctly prepared substrate
C. Appropriate setting-material coverage
D. Excessive substrate movement or structural cracking
Answer: D
Questions And Answers 2026/2027 | Complete
Questions And Answers (Verified Answers) | Exam Prep
Comprehensive Exam Guide 2026&2027
1. Under Nevada's C-20 Tiling classification, which activity is generally within the scope of
the classification?
A. Installing structural concrete walls
B. Installing ceramic and other qualifying tile products using adhesives or suction
C. Installing structural steel framing
D. Installing complete plumbing systems
Answer: B
The C-20 classification covers the installation of ceramic, encaustic, vitreous, and other tile-
like products, subject to the classification's limitations.
2. A tile contractor is preparing a bathroom floor over a concrete slab. Before beginning
the installation, what should be evaluated first?
A. Surface condition and suitability for the planned tile system
B. Color of the customer's cabinets
C. Contractor vehicle capacity
D. Final cleaning schedule only
Answer: A
A suitable substrate is fundamental to a durable tile installation. Cracks, contamination,
moisture, flatness, and other substrate conditions should be evaluated before installation.
3. A contractor notices that a concrete substrate has significant dust and loose material
immediately before applying tile adhesive. What is the most appropriate action?
A. Increase adhesive thickness to compensate
B. Install tile and rely on grout to stabilize it
C. Clean and properly prepare the substrate before installation
D. Add additional water to the adhesive
Answer: C
Bonding materials require a properly prepared substrate. Dust and loose material can
interfere with adhesion and contribute to tile failure.
,4. Which condition presents the greatest immediate concern before setting large-format
tile?
A. Tile color variation
B. Customer-selected grout color
C. Packaging design
D. Significant substrate unevenness
Answer: D
Large-format tile is particularly sensitive to substrate flatness. Excessive unevenness can
create lippage, poor coverage, and bonding problems.
5. During a layout inspection, the installer discovers that the final row of tile would be only
1/2 inch wide. What is generally the best approach?
A. Proceed because narrow cuts are always acceptable
B. Adjust the layout so cuts are balanced and visually appropriate
C. Eliminate the final row
D. Increase grout-joint width dramatically
Answer: B
A properly planned layout avoids undesirable sliver cuts and creates a balanced appearance
while maintaining appropriate joint dimensions.
6. Why are movement joints important in tiled installations?
A. They allow controlled movement and help reduce stress-related cracking
B. They eliminate the need for substrate preparation
C. They replace all grout joints
D. They make tile waterproof by themselves
Answer: A
Movement accommodation is necessary because assemblies can expand, contract, and shift.
Properly placed movement joints help prevent excessive stress from being transferred to tile
and grout.
7. A homeowner asks the contractor to install tile directly over a surface that is visibly
contaminated with oil. What should the contractor do?
A. Use thicker grout
B. Apply more tile sealer
C. Ignore the contamination
D. Correctly clean and prepare the surface before installation
,Answer: D
Oil and similar contaminants can interfere with bonding. Proper surface preparation must
precede installation.
8. Which tool is most directly useful for checking whether a tile installation is maintaining a
consistent plane?
A. Tape measure
B. Chalk line
C. Straightedge
D. Utility knife
Answer: C
A straightedge can reveal deviations in the tile plane and help identify lippage or substrate
irregularities.
9. When mixing a cement-based tile-setting material, why should the manufacturer's
specified water ratio be followed?
A. It determines only the final color
B. It helps achieve the intended working and performance characteristics
C. It eliminates curing requirements
D. It guarantees that substrate preparation is unnecessary
Answer: B
Incorrect water content can adversely affect workability, strength, bond performance, and
curing characteristics.
10. A tile installer adds substantial extra water to a setting material because it has become
difficult to spread. What is the principal concern?
A. The tile will become heavier
B. The grout joints will automatically widen
C. The material may no longer perform as designed
D. The tile will become waterproof
Answer: C
Adding water beyond the manufacturer's requirements can alter the material's designed
properties and compromise performance.
11. What is the primary purpose of a notched trowel when applying tile-setting material?
, A. To create consistent ridges that can provide appropriate coverage when the tile is embedded
B. To cut ceramic tile
C. To polish grout
D. To remove cured adhesive
Answer: A
The notched profile helps distribute setting material consistently and supports appropriate
contact between tile and substrate.
12. A tile installer discovers that a trowel is producing inconsistent ridges because several
teeth are worn. What should be done?
A. Add more water to the setting material
B. Continue because trowel condition has no effect
C. Replace or properly repair the unsuitable trowel
D. Increase grout-joint width
Answer: C
Consistent trowel ridges contribute to predictable coverage. A damaged or worn trowel can
produce inconsistent application.
13. During installation, a contractor notices insufficient setting-material coverage beneath a
tile. What is the most appropriate response?
A. Continue and fill the perimeter with grout
B. Improve the application technique and verify coverage requirements
C. Reduce substrate preparation
D. Seal the tile immediately
Answer: B
Adequate contact between tile and setting material is essential for bond and performance,
particularly in demanding installations.
14. Which condition can contribute to cracked tile after installation?
A. Properly planned movement accommodation
B. Correctly prepared substrate
C. Appropriate setting-material coverage
D. Excessive substrate movement or structural cracking
Answer: D
