CFI Quality Control & Maintenance Practices 3 — Questions and Answers
Question 1: When inspecting a completed tile installation, what is the maximum allowable lippage between adjacent tiles per ANSI A108.02 standards?
- 1/32 inch
- 1/16 inch (Correct answer)
- 1/8 inch
- 3/16 inch
Correct answer: 1/16 inch
ANSI A108.02 allows a maximum lippage of 1/16 inch between adjacent tiles when grout joints are 1/16 inch or less.
Question 2: Which type of moisture test measures the relative humidity inside a concrete slab?
- Calcium chloride test
- Plastic sheet test
- In-situ relative humidity probe test (Correct answer)
- pH test
Correct answer: In-situ relative humidity probe test
In-situ relative humidity probe tests (per ASTM F2170) measure moisture levels within the concrete slab itself, which is more accurate than surface tests.
Question 3: A customer complains that their carpet is developing permanent indentations from furniture. What is the best preventive recommendation?
- Install thicker padding
- Use furniture cups or coasters under legs (Correct answer)
- Choose a higher pile carpet
- Apply carpet protector spray
Correct answer: Use furniture cups or coasters under legs
Furniture cups or coasters distribute the weight of furniture legs over a larger surface area, preventing permanent pile compression.
Question 4: What is the purpose of back-rolling adhesive when installing sheet vinyl flooring?
- To remove excess adhesive
- To ensure uniform adhesive thickness and eliminate voids (Correct answer)
- To speed up the drying process
- To prevent adhesive from bonding to the flooring face
Correct answer: To ensure uniform adhesive thickness and eliminate voids
Back-rolling with a weighted roller after laying the flooring ensures full contact between the adhesive and flooring, eliminating air pockets and voids.
Question 5: During a hardwood floor inspection, you find that boards have excessive end gaps. What environmental condition most likely caused this?
- High humidity after installation
- Low humidity or dry conditions after installation (Correct answer)
- Subfloor was too wet
- Improper fastener spacing
Correct answer: Low humidity or dry conditions after installation
Wood shrinks across the grain and lengthwise when humidity drops, causing boards to contract and create visible end gaps.
Question 6: What is the recommended overlap when using the calcium chloride MVER test on concrete with radiant heat?
- The radiant system must be off for 48 hours before testing
- The radiant system must be off for 72 hours before testing and on for 24 hours after (Correct answer)
- No special procedures are needed
- Test must be done with heat running at full capacity
Correct answer: The radiant system must be off for 72 hours before testing and on for 24 hours after
For radiant-heated slabs, ASTM F1869 requires the system be operating for at least 24 hours before testing to normalize conditions.
Question 7: Which of the following is a sign of inadequate adhesive transfer when installing ceramic tile?
- Grout lines that are too wide
- Tiles that sound hollow when tapped (Correct answer)
- Efflorescence on the tile surface
- Lippage between tiles
Correct answer: Tiles that sound hollow when tapped
A hollow sound when tiles are tapped indicates voids beneath the tile where adhesive did not achieve full coverage or bond.
CFI Quality Control & Maintenance Practices 3
When inspecting a completed tile installation, what is the maximum allowable lippage between adjacent tiles per ANSI A108.02 standards?