Difference Between PVC and CPVC

 PVC (Polyvinyl Chloride) and CPVC (Chlorinated Polyvinyl Chloride) are both types of plastic pipes used for various plumbing and industrial applications. While they have some similarities, they also have significant differences:

Chemical Composition:

PVC: PVC is made from polyvinyl chloride resin. It does not contain chlorine atoms bonded to the polymer chain.

CPVC: CPVC is a modified form of PVC. It contains additional chlorine atoms in its molecular structure, making it more heat and chemical-resistant.

Temperature Resistance:

PVC: PVC is suitable for use with cold water and is not recommended for hot water applications. It can soften and become deformed when exposed to high temperatures, limiting its use in hot water supply lines.

CPVC: CPVC can withstand higher temperatures compared to PVC. It is suitable for both hot and cold water applications, making it a preferred choice for hot water supply lines.

Pressure Rating:

PVC: PVC pipes have a lower pressure rating compared to CPVC. They are typically used for low-pressure applications such as drainage, irrigation, and cold water supply.

CPVC: CPVC pipes are designed to handle higher pressure levels, which makes them suitable for both hot and cold water supply in residential and commercial buildings.

Chemical Resistance:

PVC: PVC is resistant to a wide range of chemicals and acids, but its temperature limitations make it less suitable for some chemical applications at elevated temperatures.

CPVC: CPVC has superior chemical resistance, even at higher temperatures, making it a better choice for applications where contact with corrosive or aggressive chemicals is a concern.

Installation:

PVC: PVC pipes are often joined using solvent cement, which creates a strong bond between the pipe and fittings. They are relatively easy to work with and are available in a wide range of sizes and fittings.

CPVC: CPVC pipes are also typically joined using solvent cement but require a specific CPVC-compatible cement due to their different chemical composition. While the installation process is similar to PVC, it's essential to use the correct cement for CPVC to ensure proper bonding.

Cost:

PVC: PVC pipes are generally less expensive than CPVC pipes. This cost difference can make PVC an attractive option for non-potable water and low-temperature applications.

CPVC: CPVC pipes are slightly more expensive than PVC due to their higher temperature and pressure capabilities, but they are still relatively cost-effective for their performance characteristics.

In summary, the choice between PVC and CPVC depends on the specific requirements of your plumbing or industrial project. PVC is suitable for cold water and low-pressure applications, while CPVC is preferred for hot water, high-pressure, and chemical-resistant applications. Always consult local building codes and regulations to ensure you use the appropriate material for your specific needs.