The Truth about CPVC Piping

It has been discovered that within buildings all over the world that the CPVC pipework used for sprinkler systems is beginning to fail. Drain pipes, hydronic systems and potable water systems that use CPVC are also failing. CPVC pipes are plastic pipes with glued joints.

The main issue with CPVC piping is that it is not chemically resistant and therefore, starts to fail as it is exposed to various chemicals and materials.

CPVC piping is resistant to most water-soluble chemicals however, it is not resistant to the majority of water insoluble hydrocarbon-based chemicals. As a result of its lack of resistance, something as simple as hand lotion washed down a drain pipe would make it fail.

Spray Foam Insulation

CPVC pipes also fail due to exposure to chemicals on their exterior such as fire caulk and in particular, spray foam insulation. Spray Foam is a preferred insulation material because it has a high R-value. Most spray foam insulation (SPF) contains fire retardant chemicals called ‘esters’ and amine catalysts that are highly incompatible with CPVC pipes and fittings. After exposure to these chemicals, CPVC piping will turn brittle, crack and ultimately fail.

Many failures of CPVC have resulted from exposure to spray foam.

After a huge drop in sales in 2008, SPF manufacturers formed the SPF Alliance (SPFA) with an aim of proving that SPF and CPVC piping were compatible and did not cause failures. The stance of the SPFA on the subject matter is subjectively stated:

“…when (SPF’s) are not properly applied there is the potential for excess heat that can lead to ballooning of the pipe and a subsequent failure.”

However, for all its merits, SPFA is not an expertly trained CPVC forensic engineer, but rather a business collective conducting tests on its on product.

Objectively, the tests were not properly conducted, and the results were not published in any scientific journal. Instead, the SPFA published a white paper synopsis of their findings. Meanwhile, lawsuits regarding CPVC failings continue.

Hydronic heating and cooling system failures

Small leaks can cripple vast systems

CPVC is often specified as piping for hydronic heating and cooling systems as it works well for this application due to its resistance to high heat. However, if there is a leak in the heat exchanger it can cripple the entire system. A leaking heat exchanger allows for refrigerant to leak into, and contaminate, the water in the piping system.

Even a small leak is disastrous for CPVC piping as it will cause the pipes to turn brittle and fail. Once the water has been contaminated, the entire system must be replaced. Due to the significant risk of contamination, piping experts and plumbers do not recommend the use of CPVC piping in hydronic piping application.

Potable Water Service Pipes (Pipes delivering drinking water)

CPVC can fail only 10% into life expectancy.

CPVC pipes and fittings are advertised for use in hot chlorinated water service because of its high heat resistance. However, some plumbers installing CPVC pipes and fittings used in continuous hot chlorinated water service, have reported that the pipes and fittings degrade and become brittle after only a few years of use.

Chris Rainaldi of Rainaldi Home Services said of CPVC pipes that:

“over a period of time, it gets brittle and cracks and breaks and the glue joints continue to deteriorate through the pipe and go bad”.

Liam Cuddy from Emerald Plumbing said:

“It’s a product we know is failing. The manufacturer knows it’s failing”.

Even though CPVC pipes continue to be used by plumbers all over the world, their failings are starting to come to light.