Every month, we seek to bring our readers insight from the worlds of home construction, home repair, and home maintenance straight from local Northwest Washington contractors in a segment we call “3 Questions.” Yep, you guessed it: we ask three questions, and the contractors answer them.

This month, we talk about sewer line issues with Bohannan T. McKenzie, owner at Anacortes Plumbing in Anacortes.

Q1: In older homes with original sewer lines, do you recommend video scoping to determine useful remaining life and replacement cost?

Let’s talk about the waste system of your home: in homes older than the mid-1970s to the early 1980s, the internal waste systems were most often assembled using either cast iron and galvanized piping or copper piping. During this era, both types were the best options available. In fact, in this current day, many commercial applications still use the cast iron piping. Since that time, however, we have discovered better ways to vent the plumbing systems. We’ve also uncovered issues with the types of fittings used in that era. Both systems have some characteristics that you should consider. With cast iron systems, the galvanized branches corrode from the inside, causing a “caking” effect on the walls of the pipe. This “caking” reduces the inside diameter, causing the pipe to be too small for waste to pass through as designed. The cast iron fittings are also prone to failure, causing leaks and root intrusion (if near or in the soil). Copper systems do not handle the caustic environment of waste, especially with the use of modern cleaning agents. This type of system is often degraded to the point that the lower-third of the horizontal piping is either paper-thin or completely rotted out. In both cases, I recommend camera-scoping the interior as well as an external visual inspection of the piping. 

Modern homes, built from the mid-1980s onward, were usually plumbed in ABS or PVC. With these systems, there have been a few cases of bad materials, but they are uncommon. Most issues with plumbing systems of this era are due to faulty install, or improper usage.

Q2: With older sewer lines, is annual maintenance necessary? 

Plumbing inspections may not need to be annual, but the frequency of inspection should increase as the piping degrades. As a professional, I would recommend you schedule an appointment with your plumber, who should inspect the piping and tell you of its condition. The piping may need replacement, but pipes throughout the home will be in varying points of the aging process. Your plumber should be able to tell you how often you need an inspection, as well as how you might plan for a future re-pipe of your home.

Q3: I’m noticing low-functional flow with some plumbing fixtures. Is there an easy way to figure out if this is the fixture itself or something more ominous with the main sewer line?

If you’re already noticing slow drainage, the best solution would be to call your plumber today. You may only need a drain cleaning, but a trusted professional will be able to show you precisely what is required.

BONUS Q: If the sewer line needs to be replaced, what are we looking at in terms of approximate cost?

I’m sure you are wondering how much a re-pipe would cost. Understand that this is mainly dependent on the design of your home, as well as how extensive the re-pipe will need to be—but it is certainly not cheap. Expect the replacement to be in the mid- to high-thousands, per bathroom. Also, expect that if the piping requiring replacement is under slab or upstairs, you will need other trades involved. Some plumbers, such as Anacortes Plumbing, can arrange this for you if you would prefer. 

About Anacortes Plumbing

Anacortes is a family-owned business and has been through the years—although it has changed families a few times. The McKenzie family has been involved with Anacortes Plumbing since 2007. The business has a sincere desire to take care of its neighbors and community. More information at https://www.anacortes.plumbing/A big “thanks” to Bohannan for his responses!