I recently tackled installing some french drains and exterior landscape drains to help direct the many pints of water that sometimes fall from the sky here in San Diego. One section of french drain was by a retaining wall, and another by a spot on our home that catches a lot of runoff. One question I grappled with was whether to use corrugated vs solid pipe. The black corrugated pipe seemed like a cheaper and easier option, but something told me I shouldn’t dismiss using schedule 40 solid, 4″ pvc pipe. I did a lot of research before diving into my project, and hopefully the insights I gained will help you with your landscape drainage or french drain project.
When we originally installed a retaining wall in our backyard, a french drain and some surface drain pipes were put in on the main length of the wall. However, I had a sneaking suspicion that a short length of the wall without drains was going to be a problem. After some unusually heavy rains in our normally bone-dry climate, I decided to dig up that portion of the wall to check moisture levels. Unfortunately, my suspicions were confirmed. After digging down what felt like 20 feet, I found a soupy mess that appeared to be about 99% water, 1% dirt. It was clear I needed to add another leg of french drain here.
“While I was at it” (coined the most expensive phrase in home improvement by our top-notch writer Phil), I decided to add a french drain by our house and several additional surface drains – all tying in to a 4″ pvc pipe exiting our retaining wall, where the deluge of water goes on to flood our neighbor’s house. Just kidding neighbor! Actually, it exits on our property into a rock and soil basin in our yard which percolates into the soil. By the way, if this article is getting you excited more more scintillating drainage content, check out the excellent article Phil wrote on how to install a channel drain.
In short, I had two sections of french drains that needed perforated corrugated pipe or perforated pvc pipe and another 50 to 70 feet of non-perforated pipe to carry the water away. My options for the pipe led me to the two main contenders: corrugated or 4″ solid pvc. Which one is best to use depends on your circumstances, budget and ambition.
Here’s a quick video overview, followed by our more detailed written analysis where I was singing a bit different tune than in the video:
Let’s take a look a few pros and cons of corrugated vs pvc pipe.
Corrugated vs PVC Drain Pipe – Pros and Cons
- MUCH easier to work with
- Bends for easy turns and easy connections
- Turns don’t need to be at 22.5, 45 or 90 degree angles
- No gluing to make connections
- Less connections on longer pipe runs
- Rapid installation
- Easy to transport (you can coil it)
- Light weight
Corrugated Pipe Cons
- Less efficient drainage
- Height variations can cause “bellies” where water and debris accumulate
- More likely to clog
- Harder to clear when clogged (snaking would likely damage the pipe
- Weaker, can be crushed
- Less durable
Solid PVC Pros
- Highly efficient draining
- Low points (bellies) in the pipe runs are less likely
- Less likely to clog
- Easier to clear when clogged
- Stronger, resists crushing
- More durable and long-lasting
- Connections more resistant to root intrusion
Solid PVC Cons
- Significantly harder to work with
- Bends are more challenging
- More connections on longer runs
- Connections in tight spaces can be challenging and require planning
- More time-consuming to work with
- Smelly, messy glue for connections
- Harder to transport and maneuver on site
More Details on Some of the Pros and Cons
Let’s talk in more detail about some of the major pros and cons.
Easy and Weak vs More Challenging and Strong
Perhaps the biggest difference between these two types of landscape drainage pipes is how easy or difficult they are to work with. If you have long, straight runs, with a little planning corrugated pipe goes down very fast. Once your trench work is complete, you can lay a 100′ coil of corrugated pipe in no time. With solid pvc, even a straight run will require 4 to 9 connections depending on whether you’re working with 10′ or 20′ sections of pvc pipe. Frankly, it’s a pain.
Have a project with lots of angles, bends, twists and turns? Strongly consider corrugated pipe – it is vastly easier to navigate around bends and corners. Corrugated is also far more forgiving in terms of installing in tight quarters or in runs that have numerous connections. For most typical residential installs, particularly for DIY landscape drainage, corrugated pipe will save you some time and aggravation.
Let the Debris Flow – PVC vs Corrugated in Terms of Drainage
Despite getting relatively little precipitation and our surface drains not being fully installed, I was surprised to find that a bunch of sediment had actually clogged the end of our existing pvc drain pipe. While testing the existing surface drain pipes, I found water was not exiting where it was supposed to (this was in part because a “temporary” drain grate was installed below grade and likely inundated the drain with muck). Even so, a little hand-clearing near the 4″ smooth pvc pipe exit cleared the drainage line.
Catching debris is something corrugated pipe is known for, particularly if there is a belly in the pipe. Those can happen if the slope on your trench is uneven. Why is it corrugated then, you might ask. Without the corrugations, the pipe would be as flimsy as a large drinking straw, with the same limited flexibility. The corrugation adds strength and flexibility. When you think of free-flowing water, a bunch of perpendicular ridges isn’t the first and most efficient thing that comes to mind. There is a reason all plumbing you might find in a home or business is smooth-walled, whether it’s ABS, cast iron or PVC. So, for preventing clogs and keeping your drain water flowing long term, pvc is the winner over corrugated pipe.
Typical Costs of Corrugated vs PVC Drain Pipe
A 100′ roll of 4″ corrugated pipe (solid or perforated) will, at the time of this article, set you back roughly $50 to $75.
Most corrugated pipe fittings such as couplings, tees, wye, etc. are in the $2 to $10 range.
All in all, corrugated drain pipe is super affordable.
100′ of 4″ schedule 40 pvc pipe (solid of perforated) will run about $100 to $200 depending on where you source it.
Most solid pipe fittings such as couplings, tees, wye, etc. are in the $3 to $10 range.
While 4″ pipe fittings are comparable between corrugated and solid pvc, you’ll typically pay way less than half (potentially as little as 25% the cost) for corrugated vs pvc pipe. If you are on a budget, corrugated is the clear winner in the cost department.
Durability of Corrugated vs PVC Pipe
A simple handling of the two pipes will instantly tell you which is more durable and crush-resistant: pvc. With that said, most landscape drain pipe doesn’t have a ton of weight on top of it. PVC is definitely stronger and more durable, but how much that will actually benefit you is up for debate.
What’s Better for Most Users, Corrugated or PVC?
If I had to do my project all over again, I would probably seriously consider corrugated pipe. It’s far less costly and vastly faster to install. It is also much more user friendly, whether you are a DIY’er or a pro. If you have a relative small job and you’re tying into existing PVC like I was, PVC might still make sense. But if I had friends ask me what they should use in their yard (particular for a DIY install), in almost all cases I’d likely recommend corrugated pipe for its ease of installation, lower cost and easier handling.