Bad Practices – Giving the CIPP Industry a Bad Rep!

Picking the right installer is KEY!! Make sure your installer is doing the best practices.

I saw an article in one of the trade publications featuring a contractor and his business that included CIPP lateral lining. While going through the article I saw a picture of their wet out operation. They laid out their liner tube on an uneven sidewalk and were running back and forth over the tube loaded with mixed resin. YIKES!

While some shortcuts are acceptable, this type of wet out doesn’t meet the ASTM’s standards for CIPP. We’ve talked about vacuum impregnation through a calibration roller which wasn’t being followed here. The really sad part of this type of wet out is that instead of being a shortcut, this type of wet out takes more time as there’s no vacuum exhausting air pockets from the tube as the resin soaks in.

EXAMPLE: We’ve all seen self-installed tinting on car windows that feature a lot of air bubbles trapped between the window and the tint. We’ve also seen bubbles in our phone protective films that contain air bubbles between the film and the screen. While it won’t cause a problem with the car windows or the phones, the remaining air pockets in the tube where no resin exists or is resin lean will allow roots to grow through the tube and cause a future failure. Pulling a vacuum for wet out, a standard for plastics in general, along with a calibration roller complies with the ASTM standards for CIPP and is faster.

Another trade magazine showed an installation of CIPP liner in a plumbing stack. The contractor cut squares out for each tie in that comes into the stack in the approximate location of each tie in. They left a large gap to make sure they left the tie-in line open and not blocked when installing the liner. The problem I saw as the gap left in the stack could allow sewage coming down the branch line to seep between the liner and the host pipe depending on the level of cleaning and prep did before installation. Sewage leaking between the host pipe and the liner not only didn’t fix the leakage problem but jeopardized the rehabilitation project.

A while back a customer called in asking how to remove a 3” liner installed in a 4” cast iron pipe. Asking how the 3” CIPP liner got there he told me another contractor didn’t have the tools necessary to clean the 4” pipe so he lined it with a 3” liner figuring it would be okay. It wasn’t. We sold him the removal equipment to take out the old liner, but this could have been avoided.

My point in showing these examples of failed installations is not to throw rocks at the installers but to get people to follow the tried and proven as well as the common practices prescribed in the standards. We’ve already seen one of the examples I listed above get the CIPP process banned from being installed in cast iron pipe. The industry is fighting the ban but in the meantime, if the local agencies governing sewer systems and building codes in your area adopted the ban in their districts you won’t be using CIPP to line cast iron pipe. If you are a contractor and want to continue practicing the CIPP trade in your area, comply with the local codes that govern the practice. If not, the industry may just end up going away.

If you are unsure of codes in your area or what documents you should follow, contact us at or call +1-888-354-6464.

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