PVC vs Corrugated Pipe: Choosing the best Conveyance for your project
When it comes to choosing a pipe type for a drainage project, contractors tend to defer to what they are comfortable with. “We only use corrugated” or “we only use PVC” is a mantra we at Central hear over and over again. Being tied to a type of pipe is more a function of repetition than it is a function of analyzing what is the best choice for a project. Cost is often the deciding factor on what type of pipe to use, but having the information to make an informed decision will go a long way to making a determination on what pipe is the best to use for a particular project. Central’s new Category Director for Drainage, Eric Cummings, walks you through the pros and cons of PVC vs Corrugated Pipe so you can get ahead.
Pros and Cons of Flexible Corrugated Pipe
The number one deciding factor in choosing to use corrugated is cost. Rolls of corrugated pipe vs sticks of rigid pipe are way less expensive. While for some this is the end all be all in terms of selection, we have to consider all factors when choosing the right pipe. Here are the additional pros for choosing to use flexible corrugated pipe.
- Ability to run curves or any shape you would like
- No need for fittings to make turns
- Ability to transport larger quantities in a work truck
Some disadvantages are as follows
- Much lower flow rates
- Since the pipe is flexible, water can sit in low spots after rain events
- Have to be more precise to dig a flat and properly pitched trench before installing
- Durability (who hasn’t dug up a corrugated pipe filled with soil and roots?)
- Need to create more pitch in the trench to create positive downhill flow.
Flow Rates of Flexible vs Smooth Interior Pipes
The first thing to consider is that a flexible pipe will need more pitch than a smooth wall interior pipe. Minimum slopes required are below:
Smooth Interior pipe is especially advantageous when you are working on a site without a lot of pitch. Using smooth wall pipe will save you over a foot of digging over a 100-foot run. Less digging means less labor which is something we all like to see.
The other big advantage of smooth interior wall pipe is very evident when looking at discharge rates. Discharge rate is also explained as the gallons per minute (GPM) a particular pipe is able to move. Referencing the below charts, we will focus on the 4 inch pipe as an example. When installing a 4-inch smooth interior pipe at a 2% slope, we are able to move 157 gallons of water per minute. When compared to corrugated, we are only able to mover 98 gallons of water per minute. For reference, a 4 inch smooth wall pipe at a 1% slope will move more water than a 4 inch corrugated at a 2% slope. See discharge rate tables below for more information on these and other pipe sizes below. The first is for smooth interior wall and the second is for corrugated.
Choosing the right pipe for a project is not always a matter of cost. The right pipe choice can save labor in terms of installation and create a system that performs better, moves more water more efficiently and creates a more durable system you will be able to count on for years to come.
At Central, we carry a wide variety of pipe sizes and types. From coils of flexible corrugated, pvc sdr35, N12 smooth Interior to PVC triple wall, we will be able to provide the pipe you need to insure proper performance. As your drainage partner, we will help you in the making the right decision for your project and then provide the material in competitively priced in stock fashion. We understand there is a lot to consider when choosing the right pipe. With knowledgeable account managers and branch personnel, we can make this decision an informed one and you will rest assured you choose the right pipe from your drainage project. Central has the pipe you need along with all the accessories required to complete your project. Please reach out to your local branch or rep to talk over how we can help!
About Eric Cummings
Eric has 25 years of experience in the landscape industry, and he has spent the last 5 years as a District Sales Manager for NDS. While at NDS, he built a detailed knowledge of both residential and commercial drainage installation. Before joining NDS, Eric was a supervisor for Stoney Bank Nurseries in Glen Mills, PA overseeing both high-end landscape design jobs in the field as well as the forcing schedule for the Philadelphia Flower
Show. At Cider Mill Landscapes, Eric designed and installed planting, hardscape and drainage projects in Delaware, Chester and Montgomery counties. Eric has a B.A. degree from West Chester University in Philadelphia