Installer Thermoplastic Exam Practice

NRCA ProCertification Roof System Installer Thermoplastic Exam Practice Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• Which of the following is a common thermoplastic roofing membrane

material?

• Modified Bitumen

B. EPDM

C. PVC

• Asphalt Shingle

Rationale: PVC (polyvinyl chloride) is a widely used thermoplastic

roofing membrane known for durability and chemical resistance.

• What is the primary advantage of a thermoplastic membrane over an

EPDM membrane? 1 / 4

• Lower initial cost
• Heat weldable seams
• Natural elasticity
• Requires no insulation

Rationale: Thermoplastic membranes such as PVC and TPO can be

heat welded, creating strong, watertight seams, which is a major advantage over EPDM that uses adhesives or tapes.

• TPO membranes are most commonly installed using which method?
• Fully adhered, mechanically attached, or ballasted
• Fully adhered, mechanically attached, or ballasted
• Torch-applied
• Loose-laid only

Rationale: TPO membranes offer flexible installation methods,

including fully adhered, mechanically attached, or ballasted systems.

• What is the typical thickness range of commercial thermoplastic

membranes?

• 10–30 mil
• 45–80 mil
• 100–150 mil
• 5–20 mil

Rationale: Thermoplastic membranes generally come in 45–80 mil

thicknesses for commercial applications, balancing durability and flexibility. 2 / 4

• When inspecting a thermoplastic roof system, which of the following is

critical?

• Color uniformity
• Seam integrity
• Insulation thickness
• Roof slope only

Rationale: Seam integrity is crucial for preventing leaks, especially

since thermoplastic membranes rely on heat-welded or chemically welded seams.

• Which roofing component provides a base for mechanically attached

TPO or PVC membranes?

• Felt paper
• Insulation boards
• EPDM membrane
• Gravel ballast

Rationale: Insulation boards provide a stable, flat substrate for

mechanically attached thermoplastic membranes.

• PVC membranes are highly resistant to which of the following?
• UV degradation
• Chemical exposure
• Physical puncture
• Algae growth

Rationale: PVC membranes are chemically resistant to oils, acids, and 3 / 4

other industrial chemicals, making them suitable for commercial and industrial roofs.

• What is the primary purpose of a cover board under a thermoplastic

membrane?

• Increase reflectivity
• Provide a smooth, durable surface for membrane installation
• Replace insulation
• Prevent snow accumulation

Rationale: Cover boards protect insulation, provide a smooth surface

for membrane attachment, and add fire resistance.

• Which tool is essential for heat welding thermoplastic membrane

seams?

• Trowel
• Hot-air welder
• Roofing hammer
• Screw gun

Rationale: Hot-air welders are used to melt thermoplastic

membranes at the seam, ensuring a strong, watertight bond.

• Which of the following is a common cause of thermoplastic

membrane failure?

• Excessive foot traffic
• Improper seam welding
• Lack of gravel
• / 4