The drain pipe is often neglected besides being one of the most important components of a home's plumbing system.
Troubleshooting the lack of running water in the house is fairly easy. Figuring out how to fix blocked drain pipe is a much harder job.
It is during these situations that many people become aware of how wastewater leaves the house.
We will cover everything you need to know about this essential plumbing system and offer useful tips to help you out of your predicament.
What Is A Drain Pipe?
When you use water to flush the toilet, wash dishes, shower, or other domestic applications, the dirty water has to leave the house somehow.
A drain pipe is part of the Drain-Waste-Vent (DWV) piping network of a house. Specifically, the drain pipe is tasked with carrying wastewater out of the house and into your septic tank or the municipal sewer system.
The main drain pipe is located under the lowest floor of your house. This might be under the foundation slab for houses that don't have a basement; or under the house for homes with a raised foundation.
Standard drain pipes are 4 inches in diameter and can be made from different materials, as we will see later in this article. Drain pipes are also sometimes called waste pipes.
Common Types Of Drain Pipes
Polyvinyl (PVC) Drain Pipes
PVC drain pipes are modern and are the most commonly used type of pipes in drainage systems. PVC is easy to work with, cheap, and hardy, and can last up to 100 years if installed properly.
The most commonly used type of PVC for residential purposes is schedule 40. Other types include schedule 80 and chlorinated polyvinyl chloride (CPVC).
The main downside of PVC is it can be hard to bend and shape to follow the desired path.
Corrugated Polyethylene Drain Pipes
Corrugated polyethylene is yet another type of plastic drain pipe.
This option is resistant to abrasion and corrosion and lasts for a long time. Also known as 'black piping,' these pipes were the first alternative to the more expensive traditional metal drain pipes.
Corrugated plastic pipes are more flexible than PVC, making them perfect for difficult terrains and unique applications. However, this option doesn't last as long as PVC.
Concrete Drain Pipes
Concrete drain pipes were the most popular choice before PVC and corrugated plastic pipes hit the market. These pipes are widely available, cheaper than metal, and durable.
Galvanized Steel Drain Pipes
Galvanized steel drain pipes are old technology and typically found in homes built in the 1950s or before.
Galvanized steel pipes have roughly half the lifespan of PVC. Most older homes replaced their old metal pipes with PVC. Galvanized steel is rarely used in today's drain pipes.
Cast Iron Drain Pipes
Cast-iron drain pipes are also old and were commonly used in the 1960s before PVC was widely available.
Cast iron is a far stronger material than galvanized steel for this purpose, but it is prone to rust.
Cast iron drains are still in use today and can last up to 100 years.
What Are Dain Pipes Used For In Your Home?
Drain pipes carry wastewater from different parts of the houses to the main drain, and then finally to the septic tank or municipal sewer line.
Drain pipes do not rely on pressure the same way that your water supply lines do. Instead, drain pipes use gravity to carry the wastewater out of your house.
For this reason, drain pipes are either installed vertically or at a downward pitch or angle.
Common Reasons Why Drains Block
Hair – This is perhaps the most common reason for blocked drains. Hair clumps together and can mix with grease and other sticky elements to form blockages in your drain.
Food Waste – Throwing solid food down the kitchen sink is never a good idea. Greasy foods are especially bad for your drainage system. They clamp together and attach to other debris to cause blockages. Tea and coffee grounds are equally bad since they do not break down and cause permanent blockages.
Poor Drainage Installation – Most municipalities require that only a certified plumber can install residential drain pipes. A shoddy DIY job can lead to pipe fractures and incorrect water flow.
Settling Soil – This cause is common for newer homes. Settling soil can cause the pipes to shift, reducing or eliminating the pitch needed for the water to flow. This also happens a lot in DIY installation.
Baby Wipes – Wipes, in general, aren't meant for flushing down a toilet. This includes so-called flushable wipes that are notorious for blocking drain pipes.
Tree Roots – Tree roots grow towards the water, and a leaking drain pipe is an attractive target. Large tree roots can damage the pipe or obstruct the proper flow of wastewater. This is one of the hardest problems to address.
Symptoms Of A Blocked Drain Pipe
Four main issues that will alert you to a blocked drain pipe.
- Strange drain noises – An early warning sign of a blocked drain is gurgling or strange noises from your toilet, pipes, plug holes, or drains. This is usually an indication of air trapped inside pipes. The air moves back up the system because of the obstruction, causing the strange noises.
- Unusual toilet water levels – You may notice that the water in the toilet bowl after flushing is below its usual level. This sometimes happens when airflow through your drainage system's vent line is obstructed, usually by a blockage.
- Water is draining slowly – this is an obvious indication of a problem with your drainage. You may notice water in your toilet, sink, or shower draining slowly or not at all.
- Foul Odor – When your drain is clogged with organic matter, such as bits of food, the matter will begin to decompose. This is the source of the foul smell. Running water accelerates the bacteria, making the smell even worse over time.
Drain Pipe Blockage: Inspection, Clearing & Prevention Methods
Now that you have a good background of how a drainage system works, it's time to get to the practical stuff.
5 Tips On Inspecting Your Drain Pipe
- Buy or rent a drain pipe camera.
- Renting is a better option since you won't be using this equipment often.
- Locate the drain access and make sure you have the tools you need to get it open.
- Use a good camera that shows the obstruction clearly. Some obstructions can be jetted off or broken down with water pressure, while others have to be removed.
- Consider wearing a respirator before opening the manhole cover for main drain blockages. Your drain pipe will have a foul smell.
5 Tips On Alleviating Or Cleaning Drain Pipe Blockage
- Make a home-made drain cleaner with equal parts of vinegar and baking soda. Create the mixture next to your drain so you can pour it in as soon as it starts fizzing.
- Take the drain apart using a wrench. Make sure you have an empty bucket under the sink to catch the dirty water. Use a torch to look inside the piping for any obstructions.
- Pour boiling water into the offending drain. Pour the water slowly, waiting a few seconds every so often. This method is effective for dissolving grease blockages.
- Straighten out a wire coat hanger and create a hook in one end. Remove the drain cover and twist the wire in. Pull it out a few times to see if you caught hair and other debris. Finish off by pouring hot water into the drain.
- Use a plunger. This will work for most minor blockages. Alternatively, mix dish detergent and hot water and pour it down the drain before plunging. The mixture is great for dissolving grease blockages.
5 Tips On Preventing Drain Pipe Blockage
- Consider putting mesh screens over your drains to trap solid wastes such as hair strands
- Avoid flushing anything other than toilet paper down your drain. Better yet, consider switching to bio-degradable toilet paper.
- Avoid disposing of solid foods in your kitchen sink.
- If your area has hard water, consider installing a water softener. Hard water causes a mineral buildup in your drains.
- Install grills on your outside drains to keep out leaves and other debris.
When Should I Call The Plumber?
Ideally, you should call your plumber as soon as you notice signs that your drain is blocked. Unless you can remove the blockage, it will simply move down the drain and block the main drain.
There is also a good chance that the problem is in your main drain.
Also, the best chance you have at properly diagnosing a blockage is to use a drain camera. It is cheaper to hire a plumber who already has the camera rather than buying or renting the equipment.
Finally, if you are experiencing a blockage in all your drains, then it is definitely time to call a plumber.
Frequently Asked Questions
How Long Do Residential Drain Pipes Last?
Under ideal conditions, PVC and ABS drain pipes can last up to 100 years. Cast iron pipes have a lifespan of 75-100 years, while concrete lasts 50-100 years.
Are All Drains In A House Connected?
Yes. All drain pipes are connected. Remember, drain pipes are part of the larger drain-waste-vent system. Drain pipes also connect to ventilation pipes.
Where Is The Main Drain Located In A House?
The main drain is located under the foundation slab, under the basement, or under the house, depending on the type of home. Most main clean-out fittings are located outside. If you can find a manhole cover, that is your main cleanout and where to unblock the main drain from.
A plunger should solve most minor blockages. Please call a plumber if none of the tips suggested here work.
Diagnosing a drain blockage is a tough job and is the first and most critical step of clearing a blockage.
Getting professional help early can help to prevent more expensive drain repairs down the line.