CFI Flooring Materials & Installation Techniques 3

Question 1

What is the primary purpose of a crack isolation membrane installed beneath ceramic tile?

Accepted Answer

To prevent cracks in the substrate from transferring to the tile

Answer

A crack isolation membrane, such as KERDI or similar products, allows slight substrate movement without transmitting the crack through to the tile surface.

Question 2

Engineered hardwood differs from solid hardwood primarily in that engineered hardwood:

Accepted Answer

Has a cross-ply core that improves dimensional stability

Answer

Engineered hardwood uses a cross-ply plywood or HDF core that resists expansion and contraction better than solid wood, making it more dimensionally stable.

Question 3

The 'wet-set' method for installing mosaic tile means:

Accepted Answer

Setting tile into a freshly floated mortar bed before it cures

Answer

In the wet-set method, tiles are pressed into an uncured mortar bed, allowing them to bond as the mortar hardens around the tile.

Question 4

What is the recommended expansion gap around the perimeter when installing a floating hardwood floor in a 20×20 ft room?

Accepted Answer

3/4 inch

Answer

A 3/4-inch perimeter expansion gap is standard for floating hardwood to allow for seasonal wood movement, hidden by baseboard or quarter round.

Question 5

Which subfloor panel product is specifically engineered to resist moisture and is preferred as underlayment for ceramic tile in wet areas?

Accepted Answer

Cement backer board (CBU)

Answer

Cement backer board (CBU) such as HardieBacker or Durock is moisture-resistant and provides a stable, non-organic substrate for tile in wet areas.

(CFI) Certified Flooring Installer Practice Test

(CFI) Certified Flooring Installer Practice Test

CFI Flooring Materials & Installation Techniques 3