CFI Tile & Stone Installation 5 — Questions and Answers
Question 1: When installing large stone slabs with significant veining (like marble), what layout practice is recommended for the best aesthetic result?
- Random placement to avoid pattern fatigue
- Bookmatching or sequential numbering from the same slab lot (Correct answer)
- Alternating slabs from different lots for color variation
- Rotating each tile 90 degrees to distribute veins evenly
Correct answer: Bookmatching or sequential numbering from the same slab lot
Bookmatching or sequential layout from the same lot ensures continuous veining patterns and consistent appearance across the installation.
Question 2: What is the purpose of movement joints (expansion joints) in a tile installation?
- To allow grout to be replaced more easily
- To accommodate differential movement between the tile assembly and substrate (Correct answer)
- To improve drainage in wet areas
- To create decorative borders between tile fields
Correct answer: To accommodate differential movement between the tile assembly and substrate
Movement joints accommodate thermal expansion, contraction, and structural movement to prevent tile cracking and debonding.
Question 3: According to TCNA guidelines, how often should interior movement joints be placed in a tile installation?
- Every 4 to 6 feet in each direction
- Every 8 to 12 feet in each direction (Correct answer)
- Every 16 to 20 feet in each direction
- Only at changes in substrate material
Correct answer: Every 8 to 12 feet in each direction
TCNA EJ171 recommends interior movement joints every 8 to 12 feet in each direction in field tile areas.
Question 4: What tool is used to check that a tile floor layout line is perfectly square at the starting point?
- 4-foot level
- 3-4-5 triangle method or framing square (Correct answer)
- Chalk snap line only
- Laser level
Correct answer: 3-4-5 triangle method or framing square
The 3-4-5 triangle method or a framing square verifies that layout lines are at true 90-degree angles before tiling begins.
Question 5: When cutting porcelain tile with a wet saw, what causes the most common blade binding or chipping?
- Using too much water coolant
- Feeding the tile too quickly through the blade (Correct answer)
- Using a blade with too many diamond segments
- Starting the cut from the glazed side
Correct answer: Feeding the tile too quickly through the blade
Feeding tile too fast prevents the diamond blade from cutting cleanly, causing chipping, blade binding, and premature wear.
Question 6: What is the correct way to install a curbless (zero-threshold) shower to ensure proper drainage and waterproofing?
- Slope the entire bathroom floor toward the shower drain
- Use a linear drain with a pre-sloped foam system and continuous waterproof membrane (Correct answer)
- Install tile directly on the concrete slab without additional slope
- Use a standard shower pan liner folded over the shower perimeter
Correct answer: Use a linear drain with a pre-sloped foam system and continuous waterproof membrane
A linear drain with pre-sloped foam and continuous waterproofing ensures proper drainage and a barrier-free, fully waterproofed curbless shower.
Question 7: Which type of stone requires the most care regarding acidic cleaning products due to its susceptibility to etching?
- Granite
- Slate
- Quartzite
- Marble and limestone (calcite-based stones) (Correct answer)
Correct answer: Marble and limestone (calcite-based stones)
Marble and limestone are calcite-based and react chemically with acids, causing permanent surface etching and dullness.
CFI Tile & Stone Installation 5
When installing large stone slabs with significant veining (like marble), what layout practice is recommended for the best aesthetic result?