How to Keep Pipes From Freezing In a Crawl Space
April 9, 2024
Home plumbing systems are some of the most confusing and intimidating for DIYers to work on, partly because there are many different types of plumbing pipes. Whether diagnosing an issue in your home, implementing a solution, or running plumbing to a new room or fixture, you must understand the different kinds of pipes and their applications.
This guide discusses the seven types of plumbing pipes you might find in or need for your home. We'll break down each Cost, discuss the pros and cons of the different styles, and include additional information about pipe measurement and selection to help your project go as smoothly as possible.
You might find seven main types of plumbing pipes throughout your home. Identifying pipes before you begin any DIY projects and knowing which pipes are suitable for different applications are crucial. The table below includes a quick look at the seven kinds of piping you might run into, the most common application of each, and the average Cost per linear foot.
Type of Plumbing Pipe | Best Used For | Average Cost (estimate per linear foot) | Read More |
Rigid Copper Pipe | Hot and cold water supply lines | $2.50 – $10 | Jump to section |
PEX Pipe | Hot and cold water supply lines | $0.50 – $2 | Jump to section |
PVC Pipe | Cold supply lines (CPVC pipe only) and drain lines | $0.50 – $2 | Jump to section |
ABS Pipe | Drain and vent lines | $0.50 – $5 | Jump to section |
Flexi Pipe | Short connections to fixtures | $5 – $20 (unit cost) | Jump to section |
Galvanized Steel and Cast Iron | Hot and cold water supply lines (outdated), drain lines and main waste lines, and vent lines (outdated) | $2 – $25 | Jump to section |
Black Pipe | Natural gas supply lines | $0.50 – $3 | Jump to section |
Best for Copper pipe is best for water supply lines, and that's typically the only application you'll see them used for in your home. These pipes can deliver water from your water main to all of your plumbing fixtures and appliances, like your water heater and water softener.
Average Cost: Copper pipe can range from around $2.50 to $10 per linear foot, depending on the pipe walls' thickness and the pipe's diameter. You'll most commonly see Type L ½-inch copper pipe behind your walls and running to your quick disconnects (speedy valves) behind your fixtures. This size pipe usually averages around $3 per linear foot.
Copper pipe is made primarily of copper, as the name suggests, so it has a shiny copper color. It's technically a copper alloy that also contains silver and phosphorus. It has long sections for running lines behind walls and several joints for 90-degree angles, T connections, and more.
There are three types of copper pipe: L, M, and K. The different letters refer to different wall thicknesses. Type L is the most common for residential supply lines.
The video below provides a quick look at how complicated connecting copper pipes can be:
SharkBite fittings are a common DIY solution for copper pipes, as they allow for quick connections without special tools or the need for sweating or soldering the pipes. These fittings are highly unreliable and will likely lead to severe leaks over time. We strongly recommend against using these fittings for any plumbing application.
Best for PEX (cross-linked polyethylene) pipe is a somewhat recent innovation in plumbing that is best for supply lines for hot and cold water in homes.
Average Cost: PEX piping averages around $1 per linear foot and ranges from $0.50 to $2, depending on the pipe diameter. The low cost makes it an appealing alternative to copper supply lines.
PEX pipe is flexible, making it easy to work with. The flexibility is thanks to the material it's made of. PEX is a cross-linked polyethylene pipe material called high-density polyethylene (HDP). It's color-coded for ease of installation — blue for cold water applications and red for hot water applications.
The pipe comes in sizes ranging from ½ inch to 1 inch. Domestic water applications typically use ½-inch or ¾-inch PEX pipe.
Best for PVC (polyvinyl chloride) pipe is best for drain lines, while CPVC (chlorinated polyvinyl chloride) pipe can be used for cold water supply lines. In most cases, PVC pipe is used to carry greywater (domestic wastewater from showers and sinks) and blackwater (domestic wastewater from toilets) to your septic system or main sewer line. PVC pipe is also highly resistant to UV light and hot and cold temperatures, so it's a common option for irrigation systems and pipes exposed to direct sunlight.
Average Cost: The average cost is around $1 per linear foot for one ½-inch piping — the most common option for fixture drain lines.
PVC pipe is usually white and has thick walls. PVC is a hard plastic, so it's relatively lightweight and semi-flexible. Unlike copper, connections for PVC pipe are easy to make using a two-part PVC glue. Home supply stores like Home Depot carry long sections of PVC pipe and a wide range of connections for all applications, including P-traps, S-traps, T-joints, Y-joints, and more.
The best for ABS (acrylonitrile butadiene styrene) pipe is for drain and vent lines in residential plumbing systems. It's typically found under sinks and other fixtures and carries greywater or blackwater toward your main sewer line or septic system. Some electricians use ABS pipe as an insulative conduit for electrical lines, so be aware of that if you're assessing an ABS pipe behind a wall.
Average Cost: The average cost of ABS piping is around $0.80 per linear foot, but the total can range from $0.50 to about $5, depending on the thickness of the pipe wall and the diameter. Most domestic waste lines made of ABS pipe are 1 ½ inches in diameter.
ABS pipes are black and rigid, so they look like darker PVC pipes. They are semi-flexible, but connections are required to run piping through your home. Much like PVC pipes, ABS pipes are joined using a cement glue specifically made for ABS material, so working with this option is much easier than copper piping. Long, straight runs and various connections are usually in stock at home improvement stores.
Best for Flexi pipe, also called supply hose, is best for making short-range connections between speedy valves — often connected to copper pipes behind your walls — and fixtures, namely toilets and sink faucets. This piping is prohibitively expensive to use over long stretches. Still, the flexibility makes it ideal for connecting plumbing fixtures to roughed-in plumbing, especially for retrofits or use in tight spaces where rigid water lines aren't realistic.
Average Cost: A flexi pipe supply hose costs around $10, but depending on the length you need, you could pay anywhere from $5 up to $20.
A Flexi pipe supply hose contains a flexible PVC hose usually enclosed within a braided steel protective layer. The connections on either end depend on the purpose of the line. In the picture above, the upper connection is made to connect to a toilet for water supply to the tank. The lower connection gets screwed onto your speedy valve. A line with two connections that look like the lower one in the picture would be for connecting a sink to a speedy valve.
Best for Galvanized steel or cast iron pipe is best for main waste lines. These pipes used to be used for supply lines, but copper has almost entirely replaced them. You'll most commonly find these used for large waste lines running to your sewer system, septic system, cesspool, or supply lines in older homes.
Average Cost: Galvanized and cast iron pipe are quite expensive, ranging from $2 to $25 per linear foot, with an average of about $18. One reason for the high Cost is the pipe size, typically 4 or 6 inches in diameter for main waste line applications.
Cast iron and galvanized steel pipes are usually the largest in your home, ranging from 4 to 6 inches in diameter. They're made of hard metal and typically black, but they could appear rust-colored if older. Generally, you'll only find these running from toilets to your main waste line and used as the main waste line, which exits your home through your foundation and runs to either a public sewage system or a private waste disposal system.
Best for: Black pipe is best for transporting natural gas into your home. It's typical to see this type of pipe running to your gas stove, gas boiler, or other appliance that uses natural gas as a fuel source.
Average Cost: Black pipe costs between $0.50 and $3 per linear foot, with an average of around $2.50. The most common size for residential applications is ½-inch-diameter black pipe.
Black pipe is, as you might guess, black. It's completely rigid, as it's made from black steel. It typically has threads on either end to connect to fittings or connections, all available in most home improvement stores. Even though this piping is used for natural gas, it's considered a plumbing pipe and requires a plumber's license to work within most municipalities.
Regardless of the kind of plumbing pipe you're working with, you should always make sure you measure the pipe carefully to ensure you get a proper fit. Most plumbing applications also do best with a specific pipe diameter, so pipe sizes are important even if you're plumbing a new area in your home. We'll detail the steps to measure your pipes below.
First, you want to measure the pipe's total diameter, including the pipe walls' thickness. Ideally, you'll use calipers for an accurate reading. Place the calipers over the pipe and take a measurement using the outside forks. Alternatively, you can use a tape measure. Just make sure you take a reading across the middle of the pipe to get the true diameter.
Next, you’ll need to measure the inside diameter. You can do this using the inside forks of your caliper or a tape measure. If you use the latter, just be sure you measure across the center and only measure from the inside wall to the inside wall.
Your last step will be to calculate the thickness of the pipe wall. You can subtract the inside diameter from the outside diameter and then divide by two to get the material thickness.
Finally, you can use your measurements to choose your pipe. You can either measure the new pipe or just buy one that matches the outside diameter and material thickness.
If you're dealing with a plumbing issue in your home, you might be intimidated by the sheer number of pipe options available at your local home improvement store. Hopefully, our information has helped guide you toward the right choice for your project. We'll also include some things to consider below to ensure you get the right pipe for your situation.
Certain plumbing pipe options are best for specific applications, so this can be the easiest way to decide what kinds of pipe are possible for your project. For example, if you're running supply lines behind your walls for hot and cold water, you only have two options: PEX and copper. Choose the type that matches your project based on our guidance above.
If you’re running water supply lines, you need to consider your water quality. Acidic water — usually from private wells — can corrode certain materials, including copper, so that PEX might be a better option.
If you have piping options based on your application and water quality needs, your budget might be an important thing to consider. For example, if PEX and copper are options for your project, PEX will be about a sixth as expensive. Keep in mind long-term costs as well, as copper lines will last longer than PEX.
The building code in your municipality might dictate what kinds of pipe you can and cannot use. For example, PEX isn’t up to code in some areas, meaning copper or galvanized steel would be your only reasonable options for hot and cold water supply.
If you’re installing pipes inside your home, most options will be just fine. If pipes will be subject to drastic temperature changes, UV (ultraviolet) light, or other environmental factors, then choosing the right pipe for your installation area can help narrow down your options.
Finally, some pipe options are far more challenging to work with as a DIYer. For example, copper pipe is harder to cut and make connections with than PEX and PVC. If you plan on doing your project yourself, you might want to consider your experience when deciding on the type of pipe that’s best.
Ultimately, the type of pipe you use for your plumbing repair or replacement project should be driven by the application. Depending on where you live and the use case for the pipe, you might have a few different options. You can use the information above as a guide to help you choose the right kind of plumbing pipe or assess which pipes you're looking at in your home if you're unsure.
The answer to this question depends on the application. Overall, galvanized steel and cast iron pipes have the longest lifespan, averaging around 100 years. However, these options aren’t ideal for water supply lines due to cost and potential leaching, so copper lines that last around 40 years are considered the most durable for hot and cold water supply lines.
PEX is superior to PVC in some cases. Specifically, it’s a flexible pipe that’s also super lightweight, making it easier to work with than PVC. The connections can also be made without glue, so ease of use is better with PEX. PEX can also safely carry hot and cold domestic water, while PVC will leach chemicals into hot water and can warp and crack over time if exposed to severe heat.
With that being said, PVC has a longer lifespan — up to around 70 years as opposed to 40 for PEX — and PVC is more affordable per linear foot.
Ultimately, neither is exclusively better, but specific plumbing applications may call for one over the other.
Copper plumbing pipes can corrode over time and slowly leach metals into your drinking water, especially if you have well water, which tends to be acidic. Copper is also one of the most expensive pipe options per linear foot. Most importantly for DIYers, cutting and connecting copper pipe can be challenging, and it requires special tools and skills that many homeowners don’t possess.
The most common type of pipe for plumbing depends on the application. As far as water supply lines go, copper pipe has long been the preferred option. For small drain lines, PVC and ABS are both popular, with PVC appearing more often in homes. For main sewer lines, galvanized steel or cast iron pipes are the most common. Black pipe is the only type you’ll typically see for transporting natural gas.
How to Keep Pipes From Freezing In a Crawl Space
April 9, 2024
What You Need to Know About Frozen Pipes
November 13, 2023
4 Signs That Your Home Has Plumbing Leaks
April 5, 2024
Home Buyers: Avoid These Flood-Prone Pipes
April 15, 2024
ASK DANNY: Are Plastic Water Pipes Safe?
April 11, 2024
How to Check a Water Meter to Find Plumbing Leaks
April 9, 2024
The Homeowner’s Guide to Repiping
April 10, 2024