What is the Difference Between PVC and CPVC?

Picking the right piping material can make all the difference in durability, safety, and long-term performance. A common question concerns the key differences between CPVC and PVC pipe. Understanding those differences will help ensure you’re using the best option for the job, whether for a home project or something on a larger scale.

If you’re unsure what distinguishes CPVC from PVC, you’re not alone. This guide will break down the differences in a straightforward manner.

What is CPVC Pipe?

CPVC (Chlorinated Polyvinyl Chloride) is a thermoplastic pipe material known for its high-temperature resistance and superior chemical durability. It is created by adding chlorine to standard PVC, enhancing its strength, heat tolerance, and ability to withstand aggressive chemicals.

What are the Benefits of CPVC Pipe?

• Higher temperature resistance: CPVC is rated for up to 200° Fahrenheit, compared with PVC’s 140°F limit.
• Stronger chemical resistance: CPVC is more resistant to acids, bases, and salts, making it ideal for industrial applications.
• Safe for hot water applications: Unlike PVC, CPVC pipe for hot water is commonly used in both residential and commercial settings.
• Durable, long-lasting: CPVC offers greater resistance to cracking and corrosion over time.

What are the Differences Between CPVC vs. PVC?

While both PVC and CPVC are used in various plumbing and industrial applications, their differences make them suited for specific uses, as outlined in the accompanying chart.

• If your system requires hot water, CPVC is the better choice.
• For cold water or drainage, PVC is often sufficient.
• Industrial settings with aggressive chemicals favor CPVC.

CPVC’s unique properties make it a preferred choice in various industries and residential applications.

1. Residential Plumbing

• Hot and cold potable water supply
• Replacement for copper pipes due to cost-effectiveness and corrosion resistance

2. Commercial and Industrial Applications

• Fire suppression systems (e.g., BlazeMaster® CPVC)
• Chemical processing and waste drainage
• High-temperature exhaust and boiler applications

3. HVAC Systems

Used in certain air handling and cooling systems due to heat resistance.

Best Practices for CPVC Installation

1. Use the Right Solvent Cement

CPVC requires a specific cement that ensures strong, leak-free joints. FlowGuard Gold® 1-Step Cement or Oatey® Orange Lava are commonly used to provide reliable, code-compliant bonding solutions for hot and cold water systems.

Using the wrong cement is a common mistake. Avoid it by reading our blog on selecting the best option for your job.

2. Prepare Pipe Properly

• Cut the pipe squarely: Make clean, straight cuts for a secure fit.
• Chamfer and deburr the edges: Smooth the edges to prevent cement blading during assembly.
• Use primer when required: Always apply primer on the pipe and fitting if the manufacturer’s instructions recommend it for a stronger bond.
• Use the right amount of cement: Apply enough cement to completely cover the pipe and fitting surfaces without overfilling. Too little cement can result in weak joints, while too much can puddle, potentially weakening the joint and leading to leaks. Ensure the cement is evenly spread, but avoid excess.

5. Ensure Adequate Support

CPVC pipes need proper bracing and support to prevent sagging, especially in high-temperature applications.

6. Provide Proper Ventilation

During installation, it's important to avoid sealing off the system too quickly, as you want the solvents to evaporate. The curing process relies on the solvents evaporating to form a strong bond.