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Why a Sewer Inspection is Essential for Home Buyers

A Sewer Scope can be the best prevention money you can spend. It will add a few dollars to your home inspection, but it's hard to put a price tag on peace of mind.

Even though you can't see it underground, the sewer line is a critical part of a home's plumbing system and when it isn't working right, watch out!

Have you ever experienced a major plumbing clog? Not being able to flush the toilet and/or and having sewage back-up in tub/shower is not fun to say the least, having experienced it ourselves a time or two in our 1960's brick ranch!

Even worse is when a major blockage causes sewage to flood the home -- this is horrendous and expensive! This actually happened to a friend of ours about 5 years ago in their 2005 3-story townhouse. After the event, they had to replace everything in the bottom level, flooring and drywall included. (And no, we did not inspect it before purchase as they live in another state!)

Out of sight can mean out of mind, so its important to remember that homeowners are financially responsible for the repair and/or replacement of their home's sewer line from the foundation out to the street where it connects with city lines or a septic tank.

Haven't we always inspected the sewer line as part of the home inspection? Well, yes and no.

A standard part of the home inspection is testing the drain and sewer lines by flushing the toilets, running the showers and sinks to determine if the plumbing system is working as it should. Home inspectors are looking for indications of clogs in the plumbing system. However, the home inspector is limited by the amount of time he's at the house and by what he can't see.

  • Drain lines can hold quite a bit of water before they will start to back up. A couple of flushes is sometimes not enough to identify a back-up in the making -- this is especially true for a vacant house in which the plumbing isn't in use on a daily basis.

  • Additionally, a change in the sewer line volume can have an impact. When a family of two moves out and a family of four moves in, that means more showers, more toilet flushes, etc. This type of added volume can be the tipping point that causes a damaged or constricted sewer line to finally back up.

  • Given that the sewer line is buried underground, we haven't been able to physically see its condition except for where it connects to the drain lines in the crawlspace (and not at all for a home on a slab).

Now with our new video-camera Sewer Scope, we can see identify a variety of repairs which may be needed due to:

  • Clogging -- Grease, hair, bath salts or food particles going down the sink or wipes down the toilet can accumulate or get lodged in the pipes causing water to back up. In a brand new home, construction debris can clog the sewer line as well.

  • Tree Roots -- Tree roots gravitate towards pipes because of moisture and can penetrate in the smallest crack, causing damage to the line and clogging.

  • Ground-Settling -- A shift in the soil due to digging, excavation, nearby construction or seismic activity can result in pipes bending and breaking. Also, improperly supported trenches can cause the sewer lines to sink or create low spots, often called “bellies." Fortunately, bellies are easy to identify via a sewer scope.

  • Ground-Shifting -- Sewer lines can detach over time. Ground shifting can happen for many reasons, such as seismic events or nearby excavations.

  • Old Pipes -- Older homes which still have an original sewer line made of cast iron, Orangeburg, clay tile and/or thin-walled PVC are now ready for repairs or replacement due to age and deterioration over time.

  • Poor Installation -- In new construction, the most common installation issues are improper joints and poorly fitted connections. Also, you want to be sure there isn't any construction debris in the sewer line before you move in. A sewer inspection can easily identify repair needs so you can alert the builder.

Plus, if we detect an issue, we’ll be able to pinpoint the location in the yard where repairs are needed!

Sewer pipes have evolved over the years, becoming more reliable. However, there are still potential pitfalls to watch out for.

  • Clay Tile -- Before 1970, many sewer lines were made with clay tile pipe. These pipes were set in the drain trench end to end from the house to the sewer main. Small gaps created at each pipe union created opportunities for root intrusion. This made it necessary to snake or clean these drains to remove these roots every 6 months to a year.

  • Orangeburg Pipe -- Many homes built between 1945 and 1972 used Orangeburg pipe for their sewer lines. Orangeburg is a fiber conduit made with wood fiber and tar pitch. Named for the primary manufacturer (Orangeburg Manufacturing Company located in Orangeburg New York), Orangeburg was an affordable alternative to metal for sewer lines. The problem with Orangeburg was its general lack of strength. The product had a life expectancy of about 50 years, but in many cases would fail in as few as 10 years. Additionally, due to the fibrous nature of Orangeburg, snaking could tear the line causing greater damage and the pressure of hydro-jetting could destroy the line. As a result, Orangeburg has no longer been used for sewer drain applications since the introduction of PVC.

  • Thin-Walled PVC Pipe -- In the 1980’s, sewer lines were being manufactured with PVC (PolyVinyl Chloride) pipe. This was a better alternative to Clay tile and Orangeburg because it was seamless, rigid and affordable. The only problem with early PVC sewer line installations was that the early PVC was thin and brittle. This product could fail under pressure causing the same issues associated with Clay Tile and Orangeburg. Today, this type of PVC is referred to as “Thin-Walled PVC”. Although it was an improvement over previous materials, its dependability was not reliable.

  • Thick-Walled Schedule 40 PVC -- In the 1980's, the material 'Thick-walled Schedule 40 PVC' started being used for sewer lines and is still being used today. This type of PVC is more resistant to pressure, breakage and breakdown.

Have the sewer line inspected no matter how old the house is.

Regardless of a home's age, it makes sense to inspect the sewer line before you buy your home. No matter how new or how well-maintained a home is, there is only one way to find out the condition of the sewer line. While every house can benefit from a sewer scope, we definitely recommend having this assessment done if you are . . .

  • Buying a brand new or newer house -- to confirm proper installation of the sewer line and that it's clear of construction debris

  • Buying a vacant house or a tenant-occupied -- to identify any clogs which may be present that the home seller may not be aware of or, if the current occupants have not reported plumbing issues to the home seller for repair

  • Buying a house built since 1990 -- to identify repair needs on older sewer lines such as deterioration, clogs, shifting/cracking/sagging and/or tree roots

  • Buying an older house built before 1990 -- to identify the presence and condition of old cast iron/clay tile/Orangeburg/thin-walled PVC sewer lines and determine if they are ready to be replaced

  • Buying any house with mature landscaping and/or large trees in the front yard -- to identify tree roots which can lead to repeated clogging

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