Home ImprovementRemodelingCleaningGardeningLandscapingInterior DesignHome AppliancesPest ControlDecks & PatiosSwimming Pools & Hot TubsGaragesBasements

How to Prevent Clogged Pipes and Drains in Older Houses

Updated on June 10, 2017
VirginiaLynne profile image

VirginiaLynne is a homeowner who likes to share her creative ideas for home renovation and home maintenance tips.

Why Clogs Happen in Old Homes

Having owned three older homes in three different states (California, Florida, and Texas), I've encountered my share of clogged drains. If you have an older home and your drains run fine, you are very lucky. If you suffer repeated clogs and calls for the plumber, this article is for you.

Every old home is different because of the materials used in the pipes, the angle of the pipes to the main line, the structure of the house, the soil and the trees in the yard. All of these elements can work to cause you problems with clogs. Some plumbers will work with you to help you uncover the problems with your home, but lots of them do make a living out of handling your clogged drain problems and may not have the interest or knowledge to help you prevent clogs at your house. Since plumbing calls are often eighty dollars or more just to unclog a drain, it pays to be pro-active in solving your own drain problems.

Our older shower is trouble prone.
Our older shower is trouble prone. | Source

How often do you have drain problems?

See results

5 Ways to Fix Sink Clog


I usually try these in this order:

  1. Snake out the sink with a tool.
  2. Use a plunger to try to force the clog down.
  3. Clean out the drain trap underneath the sink (if it has one).
  4. Pour in enzymes and let stand recommended amount of time, then pour in boiling hot water. I only use this method if I don't need the sink drained right away.
  5. Use a chemical cleaner like Draino.

Two Kinds of Blockages

I am not a plumber, but in my experience in owning 5 older houses over the last 35 years, there are generally two types of clogs at my house: sink clogs and main line clogs.

A sink clog is one which affects just one sink or shower. It is due to having lint, hair, soap, and other debris in the drain. Generally, a sink clog can be seen developing. The sink will start to drain more slowly and finally, will just stop draining altogether.

The main line clog is more serious and can happen more suddenly. Sometimes it shows up when just one sink or shower won't drain. Often, however, there are multiple sinks involved, usually on the same side of the house. Basically, what has happened in this situation is that a clog has happened not just in one sink, but somewhere down the pipes under the house or between the house and the street.

Preventing Clogs

The best way I know of to prevent clogs from happening is to use and enzyme treatment in all my sinks and showers once a month. I've tried several different types of enzymes and they seem to work about the same, but I generally use Earth Enzymes because it is easy to get on Amazon. You can also get a good main line enzyme from Roebic which is good to use about 4 times a year to make sure you have clear main lines as well.

Using Enzymes

Monthly Drain Treatment

  1. Warm Drain: Run water until it is hot. The enzymes work better in a warm environment.
  2. Prepare Enzymes: Mix up the enzyme treatment with water (if you've purchased the dry enzymes).
  3. Pour Enzymes in Drain: Pour the enzyme mix in the sink right before bed. Let it sit overnight so the enzymes can work. One benefit of using enzymes is that they can go into the toilet too. Just put the enzymes in and flush.
  4. Run Hot Water: If your drains are running slowly, you might want to do a flush the following morning with hot boiling water, or, at least, run the shower until it is as hot as possible. The hot water flush takes the gunk down the drain better. If you have a lot of build-ups, especially the first time you use the enzymes or if you have a clog, you may need to do 2-4 days of treatments to start.
  5. Use Once a Month: The important part is to use enzymes regularly, once a week at first and then every month at least. Every time I forget to use these or run out and don't get more, I end up with clogged drains.

4 Times a Year Main Line Enzyme Treatment

Other than remembering to do this, it is easy to do a main line enzyme treatment. You just measure out 1 cup and flush down the toilet for 4 days in a row (right before bed). The best one I've found (supported by the reviews at Amazon) is Roebic Main Line Cleaner. Use this once each season (4 times a year) to keep the enzymes active in your main drain. This has really worked great on our house. I've done it for two years now and not had a single time of having to call a plumber.

Why Enzymes Work

Enzyme treatments are a powdered form of bacteria that likes to eat soap, scum and other gunk that gets in your drain. When you pour the enzyme down the drain, you allow those bacteria to grow down there and feed off all the stuff you don't want to be clogging your drain. The treatment works continuously because the bacteria feed and grow. However, some things we put down the drain can kill them, which is why it is important to add new enzyme each month.

Bleach kills all bacteria and so do many harsh chemicals, including any sort of chemical you put down to unclog the drain. So if you use any antibacterial chemicals down your drain, you do need to replace the enzyme treatment. Generally, I've found that if I do remember to do this once a month, I never have drain problems.

Cause of Main Line Clogs

Build Up of Sludge: Just like your sinks get grunge in them, the main line can be filled with not only the soap and hair and other gunk, but also everything that comes down your toilet, including wads of toilet paper. Use the main line enzymes to help keep your pipes as clean as possible.

Tree Roots: Another cause of Main line clogs are tree roots getting into your pipes. However, they can also be caused by debris from remodeling projects, especially if you are re-doing your sinks and showers. One of our worst problems came after our tile was redone in our bathrooms. Too much of the grout/bits of tile and other things got washed down the drain and created a big mess and a lot of expense to clean out. In the end, the biggest culprit was a piece of black felt backing which got caught and started backing everything else up.

Plumbing Design: Another cause of mainline clogs is just the fact that the original piping gets old or wasn't designed well. There may be angles that catch stuff in them and periodically clog your drains. Moreover, you may end up having some unusual problems in the construction of your older house drainage system. We did and it took some detective work to figure it out. When our house was being constructed, there were septic tanks in our area; however, in the middle of the construction, the city finished sewer lines. Somehow, in the midst of this, our house ended up having two different main pipes which drain out to the main sewer line. This unusual situation caused a problem when the plumbers cleaned out our pipes all the way to the main line but that didn't help the drains in our house. We needed to install another clean out for the other drain

If you suspect some unusual piping, you can call your city and they may have someone who can research records and find out the original plans for your house. The other best resource is an older master plumber, who may not know exactly what is wrong with your house but may have encountered enough unusual situations in his career to be able to help you with your problem.

What You Should Do

While enzymes can help maintain and clear out slow main lines, they can't clear up a clog. In general, main line clogs are not something a homeowner can fix. If you have water backing up in more than one drain, you probably have a main line clog and you'd better call a plumber. In general, we have found that the smaller local plumbers are much better at helping us with our older houses than the big name companies. They tend to employ more experienced plumbers and quite frequently they are much lower in price. If you can't get recommendations from neighbors or friends, you might call and find out which plumbing company has experience with older homes.

Preventing Main Line Clogs

Laundry Sink: Use enzymes and lint catcher in washing machine sink drain.
Laundry Sink: Use enzymes and lint catcher in washing machine sink drain. | Source
  1. Remove Trees: If your problem is roots from trees, you may need to remove some of the trees near your home that are causing the problem. After reading about tree roots and pipes, we found out that one of the worst trees for pipes is Palm Trees. We realized that we had three palm trees planted right outside one of our bathrooms, the same bathroom which had experienced repeated problems with main line clogs. Although we regretted losing the trees, we decided that we couldn't afford these continual problems, nor the damage these trees were doing to our pipes. We removed them and have had no more problems with that shower.
  2. Root Treatment: If you do not want to remove the trees, you can also try putting a root killer down your toilets twice a year, in the fall and spring when roots are forming. These products kill the roots that are in the pipes but do not affect the tree.
  3. Limit What you Put Down Your Kitchen Drain: Even though your garbage disposal says it can eat anything, that doesn't mean you really should be putting anything and everything down your sink. The last clog I had was actually caused by rice! I knew that putting fibrous things down my drain was bad and so I always put onions, potato peels and thinks like celery in the trash. I also never put any grease down my sink, but I'd never realized that even grains like rice can swell and then clog things up if they stick on something else in the pipes. So now I am trying to put very little down my drain other than the few leftovers in my sink. It just isn't worth it! Have a small trash can near your sink and you can quickly put leftovers inside.
  4. Don't Put Hair Down the Bathroom Sink: Hair doesn't disintegrate quickly, even with enzymes, and it can quickly make a terrible tangled mess of your drain. Don't take the hair off your brush and put it down your sink or toilet. Put it in the trash, along with dental floss any and another clog catcher. For even extra protection, use a plastic hair catcher on your shower drain and install a drain trap in your bathroom sink. I've designed some DIY mesh drain shower catchers that work great.
  5. Use Enzymes Regularly: Perhaps the most effective thing you can do is to use and enzyme treatment on a regular basis. By putting these enzymes down your pipes regularly, you allow them to eat away at all the gunk that accumulates. That will keep your pipes freezer all the time. If you have trouble remembering those sorts of regular maintenance jobs like I do, then pick a particular time of the month, like the first Saturday, and put that on your calendar. Because the enzymes need time to grow in the pipes, you need to put them in at night and then not use those sinks and showers until the next morning. Do all the drains in the house at once for best effect.
  6. Install a lint catcher on the drain from your washing machine: See my hub on how to install a sink and mesh lint catcher in your laundry room.

Older homes have lots of character, but sometimes they also require more work. Just like any other possession, our pipes work better when we take care of them. Which reminds me, I'm out of enzymes and I need to order some more now!


    0 of 8192 characters used
    Post Comment

    • VirginiaLynne profile image

      Virginia Kearney 6 days ago from United States

      Hi Marcy--I am not a plumber, so I can't say about Drano hurting your pipes. However, I definitely think the enzymes would be a better choice for regular use and probably would work on the problem better because they would be continuously digesting and getting rid of the gunk. I would start with a three day program with hot water each day , then do it monthly after that. If I were you, I'd put the enzymes in all the dains at least once a month or at least when you start the treatment to make sure you are cleaning everything out. Good luck!

    • Marcy Schramm profile image

      Marcy Schramm 6 days ago

      We have a 45 year old split entry house. There has been no problem with the sinks or toilets clogging.

      The problem is with the two drains in the unfinished basement. One under the laundry tub and one about 6 feet away. (Yes, I put something over the wash machine hose that comes into the laundry tub. )

      The problem is a sewer smell. We can smell it as soon as we walk in the front door. I don’t think the drains have clogged up, because nothing has backed up. I had been putting drano in once a month, letting it set, and then running hot water in the drain. The pipes go about 150 feet to the street.

      I’ve heard drano can ruin the pipes. So would it be better to put some kind of enzymes in the drain once a month ????

      Thank you.

    • VirginiaLynne profile image

      Virginia Kearney 4 weeks ago from United States

      Hi Corrine, I've not used hot water in my toilets and I'm not sure if that would cause a problem, but since real porcelain is fired to a high temperature, I don't think boiling water should crack it. However, I have never tried it. I will remember your high pouring water idea and try it. Enzymes can sometimes work all by themselves if the drain is slow, not stopped, and you have time to wait. What I do on a slow moving drain is to treat with enzymes overnight. Then pour boiling water on it in the morning and run the water for 5 minutes or so (unless that clogs up the drain). Even if there is no further clog, I generally treat again for 2 more nights just to make sure it is all clear. When I lived in Northern California, I used ZEP. I don't know if it is still available there. Generally, I buy it online because for me it is cheaper.

    • profile image

      Corrine 4 weeks ago

      Won’t hot water into a clogged toilet cause the porcelain to crack?

      I often take a very huge kettle of luke warm water and pour from as high as I can straight into the clogged toilet and it usually clears the clog.

      Are you saying that regular use of enzymes will help keep them clean but not useful when clogged?

      We’re in Northern California, what are the best brands to use here?

      Thank you!

    • VirginiaLynne profile image

      Virginia Kearney 2 months ago from United States

      Hi Helpless--The bacteria is the same thing as the enzymes that I mention in my article. In fact, I should go back and edit to explain that. Basically, these "enzymes" are actually dried bacteria which eat soap and scum and other things that go down your drain. I think most drains probably have them in there already, but when you add extra down your drain it works better and faster. You need to add them monthly because things you put down your drain can kill them, especially bleach (we call it "killing germs" but it kills all microorganisms, including the "good" ones we need. In fact, I try not to use bleach very often and, when I do, add enzyme/bacteria treatment right afterwards. None of the enzyme products I've purchased list what bacteria they use on them. I have used several varieties and they all seem to work. I do not know if the ones intended to be used in regular drains are the same as the ones used in septic tanks, but I know that the ones I've listed in my Amazon links work really well.

    • profile image

      Helpless in Montreal 2 months ago

      Hello Virgina, I have a main drain problem where I have to pass a snake twice a year. In my basement drain sometimes the water from the floor drain comes up. I was listening to a radio station where they mentioned bacteria that can help with ceptic tanks...was wondering if it can help with my problem. What kind of good bacteria is this?

    • VirginiaLynne profile image

      Virginia Kearney 2 months ago from United States

      Hi Mrs. Mishra, the enzyme treatment will break down the food and other things the rats might be eating, which might help to get rid of them. However, the enzymes are non-toxic to humans and other mammals, so they won't kill the rats you are dealing with.

    • torrilynn profile image

      torrilynn 3 years ago

      prevention of clogged pipes and drains is easier and less expensive than the treatment of clogged pipes and drains. nice hub.

    • profile image

      Earthworm 5 years ago

      Hi Virginia and Dancing! Thanks for the positive comments..Earthworm is doing very well for people across the country.....you can both email us and we will send you some product at no charge to spread the Earthworm love.....Virginia, we very much appreciate your business and kind comments....

      mention that you saw me here...on hubpages...and please like us on FB..

    • VirginiaLynne profile image

      Virginia Kearney 5 years ago from United States

      Thanks Dancing Water--I will have to look up the Earthworm enzyme treatment. Great idea.

    • Dancing Water profile image

      Dancing Water 5 years ago

      Thank you for a hub that is most likely relevant for all of us. I use Earthworm enzyme treatment, which doesn't harm the environment. The enzyme idea is an excellent one. Thanks again!

    • VirginiaLynne profile image

      Virginia Kearney 5 years ago from United States

      Furniturez--you are right that Drano can sometimes work well, but it it doesn't then you are stuck with a sink full of something toxic you can't put your hands into. I usually try to see if there is any hair or guck stuck in the sink by using a snake or this wire I have that extracts stuff (has velcro on the end). Often that gets the drain going a bit, then drano or enzyme treatments work. If I do use drano, I follow it up with enzymes for 3 days in a row and then once a month afterwards to keep it clear.

    • furniturez profile image

      furniturez 5 years ago from Washington

      Sink clogs can be quite nasty... for the smaller ones use Drano, that's always worked for me. Thanks for sharing!

    • VirginiaLynne profile image

      Virginia Kearney 5 years ago from United States

      Jaye--we are great tree lovers but also decided that they needed to go to save our plumbing! One alternative that I learned about is to put copper sulfate down your toilets twice a year. You can get it at Home Depot in plumbing section. It kills the roots in the pipes.

    • JayeWisdom profile image

      Jaye Denman 5 years ago from Deep South, USA

      Can I identify with the tree roots in the main line problem! A short time after I bought this mid-century ranch style house in 2000, the calls to the plumber began. Soon he was on speed dial! Finally, he suggested checking the entire line system using a camera. The line was full of tree roots. Don't ask me what I said about the idiot who planted a magnolia tree right in front of the house within two feet of the main water line!

      Naturally, the tree had to be taken down, and (naturally, since I live in Mississippi, where the Magnolia tree is the "state tree", some of my neighbors thought it was HORRIBLE for me to do so, but none of them offered to pay my plumbing bills).

    • VirginiaLynne profile image

      Virginia Kearney 5 years ago from United States

      Glad you have found out the problem seanorjohn. Plumbing problems are so difficult to deal with.

    • seanorjohn profile image

      seanorjohn 5 years ago

      Wish I had read this informative hub a few years back. I have onl recently discovered that there is a design fault on my mains drains. The system installed in 1910 is called the Windsor trap and is the main cause of water backing up and why we have had to call out a plumber twice a year. Voted up and useful.

    • VirginiaLynne profile image

      Virginia Kearney 5 years ago from United States

      tipstoretireearly--love your name, by the way. Glad enyzmes are working for you so far. I think the hardest thing to do is to remember to do it monthly. I just did mine last week and was thinking that I ought to put it on the calendar.

    • tipstoretireearly profile image

      tipstoretireearly 5 years ago from New York

      Very useful hub! I recently started using enzyme treatments for my older house. So far so good.

    • profile image

      aboutpipes 6 years ago from 4913 Chastain Avenue, Unit 30 Charlotte, NC 28217

      With regular care, a clogged sink drain can be avoided. However, should this situation arise, try clearing the drain with ordinary baking soda and vinegar. Use a plunger afterward to add air to the drain to clear it. This usually is the first line of defense for clogged drains. If this doesn't clear the drain, you may need one of the chemical drain cleaners available in most hardware stores. Today, drain snakes are also available for household use. These can work to clear drain up to 25 feet along pipe lengths.

    • VirginiaLynne profile image

      Virginia Kearney 6 years ago from United States

      Preacherdon--yes, the enzyme treatments are about the only thing you can put down a toilet. Since doing this hub, I've been looking at different enzyme treatment products. None of them list what exactly is the bacteria they include--trade secrets I guess. So I'm not sure if any is better than another. What is nice about the Drano product is that you don't have to mix it. You just pour in in. Also, I think it is much more widely available and so you can pick it up with another trip to Walmart or whatever. However, I think it is probably more expensive than the granulated kind. I use both. Sometimes I just want to get something done quickly!

    • preacherdon profile image

      preacherdon 6 years ago from Arkansas

      Thanks for the tips. I didn't think about the rice. I'll have to keep that in mind. Is Drano Max Build-up Remover an enzyme and can it be used in the toilet as well? Voted up and useful.

    • Simone Smith profile image

      Simone Haruko Smith 6 years ago from San Francisco

      Great advice! Enzyme treatment, as an option, absolutely fascinates me. I'm also glad to hear about some preventative measures I can take, since I'm not a big fan of dealing with things once problems get out of hand!

    • ershruti304 profile image

      ershruti304 6 years ago from Shimla

      Nice hub and touched the real aspect of day to day activities.

    • Phil Plasma profile image

      Phil Plasma 6 years ago from Montreal, Quebec

      Your tip about the monthly enzyme treatment is one I had never heard. Thanks for sharing! Voted up and useful.