The Root of the Problem

See how a new technology can improve the condition of your home's plumbing.

To grow and survive, tree roots seek two things—water and fertilizer. They can, of course, get these from rain and from normal soil, but unfortunately, household drain lines are also an excellent source of water and waste products that trees can use as nutrients.

Roots are even drawn to unbroken pipes, says Dan King, owner of six Mr. Rooter Plumbing franchises in Nevada, Washington, and Oregon. The combination of warm temperatures inside a sewer drainpipe and cool soil temperatures outside cause moisture to form on the outside of the pipe. The moisture rises through capillaries in the soil and the fine thin roots of trees and bushes track the rising moisture down to its source—the pipe. The roots will grow alongside and around the pipe to lap up the moisture, but they won't cause a drainage problem unless there's a break in the pipe.

"There is a misconception that roots are the problem, but really the pipe is the problem," says King. "The roots cannot get in the pipe if there is not a crack or bad joint." Modern drain lines are made from pliable plastic (either PVC Schedule 40 or ABS Schedule 40). Unless it has been installed improperly, the solvent-based fusion welding technique used to join together lengths of plastic piping makes it extremely hard for roots to gain entrance to the drain line.

Older drain lines, however, were made from a variety of materials that were more susceptible to the sorts of cracks, breaks, and deformation that might give roots an opening. And once roots do gain an opening, that's when trouble really starts. "If there is a crack or bad joint, the roots will go through the crack inside the drain line and then start to use the high-nutrient food source inside the line to grow," says King. He has seen situations where very fine root tendrils have entered the pipe and blossomed into root balls that cause major blockages.

What are the signs of root intrusion? Sometimes you won't know until there's a sudden major backup, with the lowest fixture in the house being flooded first. That means if your family primarily uses an upstairs bathroom, you might not know you have a root intrusion problem until you come downstairs and find a big mess in the bathroom.

But King says homeowners can keep an eye out for certain warning signs. If you fill a sink with water and let it drain, you should eventually see a vortex where the water exits the sink in a swirling, cyclonic action. When you can no longer see that vortex, it might be a good time to have Mr. Rooter come out and take a look. Hopefully the problem is just due to a buildup of hair, grease, or detergent, but you don't want to take chances where root intrusion might be involved.

Don't panic, but don't ignore potential problems, either. Root intrusions are widespread. "We see problems created by roots all the time," says King, who estimates that he performs a couple of root intrusion fixes per day. SOLVING THE PROBLEM If you do have a root intrusion, you might think the easiest thing would be to simply cut away the roots, but King strongly recommends against this course of action. "Cabling a line and cutting the roots is like pruning a tree," explains King. "We prune trees to promote their growth. Similarly, when we ‘prune' the roots, we only end up accelerating their growth." In any case, once the roots have gained access to the pipe, they begin to break up the pipe even more as they grow. If you just address the roots without worrying about the underlying pipe condition, King says, the pipe can deteriorate to the point that it is totally destroyed.

So how does Mr. Rooter approach a root intrusion problem? First, King uses a cable machine with a spearhead on the end to poke a hole in the blockage and let any stopped-up water drain out. He then sends a sewer video camera down the line to locate the damaged section of pipe. This camera allows Mr. Rooter to determine whether the problem is in fact roots and not some other type of blockage. Whatever the case, Mr. Rooter will show the homeowner the problem on the video camera's monitor and agree on a permanent fix—either a spot repair on a portion of the line or a complete line replacement. Particularly if there are several breaks in the line, a full line replacement will generally be much more cost-effective. Furthermore, the new PVC or ABS plastic drain lines mentioned above are much less prone to cracking or joint problems, and thus much less susceptible to root invasion. Not only can a line replacement make sense from a financial perspective, it also provides peace of mind, thanks to the warranties that Mr. Rooter offers on new drain lines.

Technology to the Rescue

It may surprise you to learn just how far roots will travel to access the moisture produced by your drain line. King says he has seen cases where root invasions are traced back to bushes two houses over and several hundred yards away. But while you can't prevent roots from finding your drain line, it's still a good idea to know where your drain line runs when you are landscaping your property and particularly when you are planting trees. You don't want to plant a tree on top of a drain line, because the weight of the tree could actually push down on the pipe below, causing a "belly" where waste could accumulate.

How can you determine where your drain line runs in order to steer clear when planning your landscaping? You probably don't have a map of where the sewer line runs through your yard, but Mr. Rooter can help with that too. Many of the sewer cameras that Mr. Rooter uses have a locator beacon within the camera head. The camera is inserted 10 feet into a sewer line, the camera is located using a metal detector-type device, a little flag is placed in the lawn at the appropriate point, the camera is moved another 10 feet down the line, another flag is placed, and so forth—all the way to the property line.

If you're purchasing a new home, having Mr. Rooter perform a video inspection of the drain lines as part of the overall home inspection process could be a smart decision. Older homes without the newer plastic drain lines could be at particular risk of root intrusion, but even newer developments can have problems if the PVC or ABS piping suffers from faulty construction.

King notes that several Mr. Rooter franchises throughout the country now have the ability to replace a line with little or no excavation. If the pipe in question is in overall good shape, but has bad joints, Mr. Rooter can insert an epoxy-based fabric liner that essentially creates a new pipe inside the old one. Even if roots have seriously damaged a pipe, a technology called pipe bursting can pull a new pipe into place without extensive excavation. It's good to know that if you have nice landscaping in place, a very deep drain line, or even concrete running over the line, Mr. Rooter's technology can save you time and trouble.

Where the Damage Starts

How do roots enter pipes in the first place? Various types of pipe were used in household plumbing in the past, each with its own vulnerability to roots:

Orangeburg: Rolled tar paper made into a smooth lightweight pipe. Orangeburg is unfortunately so soft that if roots get alongside it, they can actually collapse the pipe.
Concrete: Tough but inflexible. Root intrusion typically occurs where sections of pipe fit together. Cracks and separation can occur when ground settles.
Clay: Just as inflexible as concrete, but not as tough. Like a clay shingle roof, when it cracks, it breaks, giving roots plenty of intrusion possibilities.
Cast Iron: Soil acidity and chemical detergents can cause corrosion over a period of 20 to 25 years, giving roots access.
PVC/ABS: This is the primary product used nowadays in household piping. In some markets across the country, PVC has only become the plumbing standard within the past 10 to 15 years. Made from flexible and durable heavy-walled plastic, PVC holds up well against root intrusion when installed properly. Roots can usually only find their way in if two sections of pipe were not joined or secured properly, allowing separation to occur over time.