CFI Cheat Sheet 2026

The 30 highest-yield CFI facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What does the AC (Abrasion Class) rating system classify in laminate flooring? → Wear layer durability under foot traffic
2. What is 'efflorescence' and how does it commonly appear in tile and stone installations? → White powdery deposits on grout or stone surfaces caused by salt migration
3. What is a key advantage of laminate flooring? → Durability and cost-effectiveness
4. A 100 sq ft room needs VCT. Each tile is 12"×12". With 10% waste factor, how many tiles should be purchased? → 110 tiles
5. A customer wants to compare bids and asks you to itemize your estimate. Which approach best demonstrates professionalism? → Itemize materials, labor, subfloor prep, and disposal separately
6. A flooring installer uses a tapping block during plank installation to: → Protect the plank's locking edge while tapping planks together with a mallet
7. What relative humidity (RH) reading at 40% slab depth is generally the maximum threshold for installing most resilient flooring? → 80% RH
8. Which backing type on carpet allows moisture vapor transmission and is preferred for below-grade slab installations? → Action back (woven)
9. Which condition would cause a floating LVP floor to buckle after installation? → Leaving insufficient expansion gap at the room perimeter
10. What is the recommended maximum gap between the subfloor and the bottom of a transition track before additional shimming or leveling compound is required? → 3/16 inch
11. When cutting porcelain tile with a wet saw, what causes the most common blade binding or chipping? → Feeding the tile too quickly through the blade
12. Porcelain tile is distinguished from standard ceramic tile primarily by its: → Lower water absorption rate (≤0.5%)
13. What type of drill bit is recommended for pre-drilling pilot holes near the end of hardwood flooring planks to prevent splitting? → Brad-point bit or countersink bit
14. A customer reports that new carpet installation has visible 'shading' or 'pooling' — light and dark patches that change with viewing angle. What is the cause? → Normal pile reversal caused by foot traffic and vacuum direction
15. What type of core material is used in the vast majority of laminate flooring products on the market? → High-density fiberboard (HDF)
16. Prefinished hardwood flooring differs from site-finished hardwood in that it: → Has factory-applied finish requiring no on-site coating
17. When calculating square footage for a room with an L-shaped floor plan, what is the correct approach? → Divide the room into rectangles, calculate each area, then add them together
18. Which condition in a wood subfloor requires correction before installing hardwood flooring? → Subfloor deflection exceeding L/360 of the span
19. Which of the following hardwood species has the HIGHEST Janka hardness rating among commonly used US flooring species? → Brazilian Cherry (Jatoba)
20. What is the minimum compressive strength required for a self-leveling underlayment used beneath ceramic tile? → 3,000 psi
21. Which type of seam tape requires a seam iron for activation during carpet installation? → Hot-melt seam tape
22. What is the risk of improper surface leveling? → Uneven flooring and damage
23. When staggering hardwood flooring end joints, what is the minimum recommended offset between joints in adjacent rows? → 6 inches
24. Which of the following is NOT an acceptable subfloor for glue-down LVP installation? → Existing single-layer vinyl
25. What is the primary purpose of 'back-rolling' adhesive before installing glue-down hardwood? → To ensure uniform coverage and collapse air pockets in the adhesive bed
26. When installing carpet over a wood subfloor, tack strips should be positioned: → Approximately 2/3 the carpet thickness away from the wall
27. To find the center of a room for a centered layout, an installer measures 24 feet on one wall and 16 feet on the perpendicular wall. Where is the center point? → 12 ft along one wall and 8 ft along the other
28. A homeowner wants to use a steam mop on their sealed hardwood floors. What should you advise? → Steam mops should never be used on hardwood floors
29. When is a moisture barrier underlayment required under a floating laminate floor installed over concrete? → Whenever the concrete subfloor is at or below grade
30. When using a floor grinder to prepare a concrete subfloor, which PPE is most critical to prevent long-term health damage? → N95 respirator or higher