C33 Identifying and Remedying Paint Failures and Defects 2

Question 1

A newly painted exterior wall exhibits small, round craters exposing the substrate. What is the most likely cause of this defect?

Accepted Answer

Contamination by silicone or oil on the surface before painting

Answer

Insufficient film thickness

Answer

Using too small a roller nap

Answer

Applying paint in direct sunlight

Question 2

What causes intercoat adhesion failure between primer and topcoat on a steel surface?

Accepted Answer

Applying topcoat before primer has fully cured or exceeding the recoat window

Answer

Using the same brand for both coats

Answer

Using a brush instead of a roller

Answer

Applying primer in two thin coats

Question 3

A C-33 contractor notices white, powdery deposits forming on a freshly painted masonry wall. What is this defect called?

Accepted Answer

Efflorescence

Answer

Chalking

Answer

Blooming

Answer

Saponification

Question 4

What is saponification in the context of exterior paint failure on new concrete?

Accepted Answer

Chemical reaction between alkali in concrete and oil-based paint, breaking down the binder

Answer

UV degradation of the paint film

Answer

Physical cracking due to substrate expansion

Answer

Mold growth under the paint film

Question 5

A customer complains about visible brush marks in the dried paint on interior trim. Which factor most contributes to this defect?

Accepted Answer

Paint drying too quickly before it can level, often due to low humidity or excessive brushing

Answer

Using a premium brush with flagged bristles

Answer

Applying too many coats

Answer

Using semi-gloss instead of flat paint

Question 6

An exterior painted surface shows irregular, map-like cracking patterns that expose the substrate. What type of paint failure is this?

Accepted Answer

Mud cracking

Answer

Alligatoring

Answer

Checking

Answer

Wrinkling