Building an efficient plumbing system requires the right materials and tools. Individuals often get confused when it comes to choosing one between CPVC pipes and GI pipes for their plumbing systems. The basic difference relies in their making; Chlorinated Polyvinyl Chloride is a thermoplastic material that is produced by chlorinating the PVC resins to offer a robust solution for both hot and cold water applications. GI pipes, on the other hand, are Galvanised Iron pipes made using iron for building pipeline purposes. CPVC pipes have an advantage over GI pipes (Galvanised Iron pipes) when it comes to hot and cold-water applications. In this blog, you will learn all about why choosing CPVC pipes like those from FlowGuard Plus would be your best bet.
Understanding the key differences between CPVC Pipes & GI Pipes
To understand how CPVC is better than GI, you must first understand the key differences between them.
- CPVC pipes are resistant to corrosion whereas GI pipes are prone to rust over time thus making CPVC a more durable choice in comparison to GI pipes.
- CPVC pipes are generally easy to install via cold welding. However, GI pipes demand more man hours and if not installed properly, they can cause breakage and leakage issues.
- The bacterial growth in GI pipes is comparatively higher than that in CPVC pipes.
- Unlike GI pipes, CPVC pipes are resistant to the formation of scales. This is why there is no buildup or any formation that can impede or cause loss of water pressure.
- CPVC pipes are exceptionally chemical-resistant and remain unaffected by chlorine present in the water supply.
- CPVC pipes are also a more cost-effective option in comparison to GI pipes.
How does CPVC outperform GI?
GI or galvanised iron pipes are becoming obsolete due to the use of CPVC pipes, which are non-corrosive, more heat-resistant, and flexible. Furthermore, despite being coated with a protective zinc layer, galvanised pipes are greatly susceptible to corrosion in cold climates and near salty waters because of the high electrical conductivity of salt. This gives CPVC pipes an upper hand in terms of applications across both residential and commercial sectors. Simply put, CPVC technology was designed particularly to meet the demands of industrial processes. CPVC pipes outperforms GI pipes in several ways. Unlike GI pipes, FlowGuard® Plus CPVC, in particular, is a material that can withstand prolonged exposure to high heat and pressure while also providing superior corrosion resistance.
Advantages of CPVC over GI
When it comes to comparison between CPVC vs GI pipes, there are a few advantages of CPVC over GI, you must look at:
- Corrosion: Metal piping systems excel at handling clean water with a neutral pH. However, if the pH exceeds 7 or the pipes get exposed to salt (through seawater), the metals begin to corrode. In contrast, CPVC pipes resist corrosion from acids, bases, and salts, allowing the aggressive ions to flow right past the CPVC while remaining unaffected by them.
- Scaling: Ions may settle onto the pipe walls if a metal is exposed to a fluid outside of its solubility range. Scaling is a greater concern in processes that involve magnesium, calcium, iron, aluminium, and silica. CPVC, on the other hand, has a lower affinity for scale formation than metals and thus poses fewer scaling concerns.
- Safety: CPVC when compared to GI has a very low thermal conductivity, which further limits the workers’ exposure to burn hazards. CPVC cannot withstand fire thanks to its Limiting Oxygen Index (LOI) of 60. Unless a flame is continuously applied to it, the CPVC pipe or CPVC fitting will not burn, and it will stop burning as soon as the ignition source is removed. CPVC is easier to handle. This contributes to less worker strain and injury during installation. It also eliminates the need for heavy machinery during the installation process.
- Installations Cost of CPVC vs GI: The galvanised iron pipe price is relatively higher than that of CPVC. Here are a few reasons why CPVC is a more cost-effective option:
- In the case of metals, specialised welding techniques, equipment, and highly skilled labourers are needed to limit the chance of corrosion, which increases the cost. CPVC solvent cement welding is a two-step process that is not as expensive as the metal’s.
- Fewer workers are needed to carry CPVC pipes as they are lighter in comparison to GI pipes.
- The maintenance costs of GI pipes are higher than those of CPVC.
Frequently Asked Questions on CPVC vs GI
- Is GI pipe suitable for hot water?
No. GI pipe is prone to corrosion, hence making it unsuitable for hot, softened water service. Whereas, CPVC pipe for hot water is the recommended option for your plumbing system.
- Is GI pipe rust-proof?
No. Acidic water is one of the major reasons for the rusting of the GI pipes.
- Are CPVC pipes more resistant to corrosion compared to GI pipes?
Yes. CPVC pipes, when compared to GI pipes, prove to be more corrosion-resistant.
- What is the expected lifespan of CPVC pipes compared to GI pipes?
CPVC pipe materials are designed to have a service life of about 50 years for both hot and cold water applications. GI pipe materials, on the other hand, can endure up to 50 years in rural areas with less pollution; however, in urban polluted regions, their lifespan decreases by 50%.
Binay Agrawal, a highly experienced and accomplished professional, currently holds the position of Business Head of the TempRite South Asia division at Lubrizol India.