Before installing a piping system, you need to be aware that new piping materials can have defects. Defects can occur during manufacturing, and most manufacturers have strict procedures for inspecting and testing the pipe before it leaves the factory. Freight damage can occur during shipping and transit to the wholesale distributor. Cast iron pipe can crack or break when handled roughly. Plastic piping can be damaged if not stored properly or if exposed to direct sunlight for extended periods. Soft metal tubing can be bent or pushed out of round, making installation difficult. Rough handling of pipe at the job site can also result in damage. Open ends of pipe can collect debris during shipping and before or during installation. You need to inspect for and identify these types of damage before you install pipe and tubing.

Inspect Pipe for Defects

Despite quality assurances, piping can arrive at the job site with damage. It is important that you take the time to inspect each pipe or fitting carefully before you install it. Discovering a defect after the pipe has been installed and is under test is costly and time-consuming or, at best, irritating. Time is wasted by removing test pressure, draining the system, repairing the defect, reassembling, and finally, retesting.

Once the pipe has been cut and reamed, inspect the pipe ends for signs of deformity or damage. Any splitting, out-of-round shape, or excessive burring on either the inside or the outside of the pipe should be corrected or replaced before attempting to join the piping. Deburring is referenced in most pipe assembly instructions and cannot be over-emphasized. Once the pipe end has been formed, it is extremely difficult, if not impossible, to ream it without damaging it beyond further use. Besides causing possible leaks, failure to ream piping and tubing will result in cavitation, friction loss, noise, and erosion.

Detecting Defects

When a defect is found, you can either reject the product or cut out the defect (damaged section) and use the undamaged section of the pipe. You would expect to pay less for a damaged product. Accepting a damaged pipe means you have chosen to accept defective materials. Before doing this, you must consider pride in your workmanship and the reliability and safety of the product for as long as the system is in use. Equally important is that using defective piping might invalidate manufacturer warranties.

When the pipe has been received, visually inspect each pipe for the following:

• Is the pipe straight? Look along the length of the pipe. Is it is curved or bent? You will need to decide whether you can use the pipe. A bent drainage pipe will present issues when you try to lay the pipe at a specific even and continuous slope.
• Are the pipe ends damaged or out of round? If the end is damaged, it will have to be removed before you can make a good connection.
• Inspect the circumference of coiled copper tubing to see if it has been pinched or flattened.
• Inspect cast iron drainage pipe for cracked ends or pinholes in the casting. Tap the end of the pipe with something solid or on the ground. Listen closely for a rattling sound, which indicates a crack of some kind.
• Cast iron pipe can also have ridges and depressions caused by uneven casting that won’t be evident by “sounding.” Ideally you can detect these irregularities by feel before the pipe is installed by running a hand along the outside of the pipe. But most often, these irregularities are discovered through failed pressure testing caused by being out-of-round or otherwise defective and should be removed and replaced upon discovery.
• When receiving steel pipe with bevelled, grooved, or threaded ends, inspect the grooved and threaded end sealing surfaces for scratches, gouges, nicks, or other damage.
• If piping is coated for permanent corrosion protection and not just for not shipping, check to see if the coatings have been damaged. You may have to repair or cut out the damaged sections. Refer to the manufacturer’s specific instructions on repair of damaged products.
• Inspect the pipe bore for blockages or debris on receiving and immediately before installation. Tilting the pipe toward the vertical will allow any lose debris to fall out of the pipe. Debris in a pipe can cause no end of problems when the system is put into service.
• Plastic piping can be seriously damaged by extended exposure to the ultraviolet rays in sunlight, especially if the pipe does not have ultraviolet protection.
• Check PVC plastic for cracks, discoloration, gouges, and scratches.
• Check PE and PEX for discoloration, gouges, and scratches.

Determine Environmental Effects

Both environmental conditions and faulty, defective materials can contribute to piping installation problems. Here are some environmental factors to consider before installing piping.

• Will the constituents contained in the soil have a detrimental effect on the pipe? High salt content necessitates the installation of pipe materials with better resistance to corrosion.
• Is the ground boggy? If so, there might be too much settlement for a normal installation, and piping may have to be supported using hangers imbedded in the slab-on-grade or suspended from the edge of the footing. Also, cast iron pipe installed underground in these conditions could crack, so plastic pipe may be a more acceptable choice.
• Is the atmosphere around the piping likely to be corrosive? If so, plastic rather than metal piping may be better.
• If the finished installation will be subjected to a lot of moisture, the pipe and the hardware used to support it may need to have a higher corrosion-resistance rating than normal. Outdoor exposed piping is an example of this.
• Check to see if there is going to be excessively high or low temperatures surrounding the pipe. Wide swings in ambient temperatures can necessitate alternative pipe types.
• If piping is installed in areas where there is a lot of paint and coatings being applied close to the pipe, it may be a good idea to check the pipe’s compatibility with the coatings.
• If the installed piping is going to be in direct sunlight, the effects of expansion/contraction and of UV rays will be an issue. ABS pipe installed in direct sunlight will undergo a lot of expansion and warping, which can cause problems with grade in drainage systems. PEX tubing should never be exposed to direct sunlight for extended periods, either before or after installation, and pipe failure could result if not protected.
• Has the plastic pipe been stored in direct sunlight? If so, check with the manufacturer to ensure that the pipe can still be installed without threat of failure or of voiding warranties.

Inspect Pipe for Proper Markings

The various codes that pipe installations must conform to will typically specify pipe or tube according to the standard that it was manufactured to. For instance, the National Plumbing Code of Canada specifies both in the body of the Code (2.2.6.1 (1); 2-8 Division B) and in Table A-2.2.5., 2.2.6. and 2.2.7 “Summary of Pipe and Fitting Applications” (2-80 Division B) that cast iron soil pipe used in a drainage or a venting system must conform to the CSA B70:19 (R2024) – Cast iron soil pipe, fittings, and means of joining standard. Because there is enough space on the pipe itself, a reference to that standard is painted or indelibly marked onto the pipe, and inspectors will look for that marking for acceptance. If it’s not evident, they may not accept the installation. Cast iron pipe is fairly easily recognizable, so is rarely, if ever, mistaken for anything else.

Where copper tube is concerned, there are at least five different grades available on the market that could be installed, and the pipe/tube marking becomes more of an issue. The various codes may say that the markings have to be visible after installation so that an inspector can readily determine if the grade of copper used is correct for the application. Besides having the relevant standard applied in ink to the pipe or tube, the colour of the ink is also used to differentiate between the grades. Further to that, copper tube is embossed (etched), indicating the grade at specific points along its length, in case the inking isn’t identifiable.

Installers may be required to access codes and manufacturers’ literature to determine that the proposed pipe type is in fact correct for the application. In some instances, the type of pipe chosen may not be acceptable to the building specifications, even though it conforms to the plumbing code. Remember that building specifications can be and sometimes are more stringent than the codes involved. Always consult local codes, as well as building specifications and manufacturers’ literature, before installing any pipe or tube.

Self-Test D-1.5: Describe the Methods of Manufacture of Piping and Tubing

Complete Self-Test 1.5 and check your answers.

References

BC Industry Training Authority. (2019). Piping trades apprenticeship program: Use Tools and Equipment—Level 1 harmonized [Binder]. Crown Publications, Queen’s Printer for British Columbia. https://www.crownpub.bc.ca/Product/Details/7960000261_S

• Plumber: Competency D-1 Prepare Pipe
• Steamfitter: Competency D-4 Layout and Install Piping and Tubing
• Sprinkler Fitter: Competency D-1 Prepare Pipe and Tubing

CSA Group. (2019). CSA B70:19 (R2024): Cast iron soil pipe, fittings, and means of joining. https://www.csagroup.org/store/product/CSA%20B70%3A19/

National Research Council Canada. (2025). National plumbing code of Canada: 2025. Government of Canada. https://nrc-publications.canada.ca/eng/view/object/?id=c97ac796-01fc-4383-9c68-b271db2802cf

Media Attributions

All figures are sourced from Industry Training Authority (2019) and/or Camosun College (2019) and are used under the Creative Commons Attribution 4.0 (CC BY 4.0) licence unless otherwise noted. Images copyrighted by the BC Industry Training Authority are licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 (CC BY-NC-SA 4.0) licence.