PVC is usually the first choice of many plumbers for most plumbing activities. They are strong, durable, and lightweight. At the same time, they resist weathering, chemical corrosion, rotting, and environmental stress. The two common PVC types used include Foam core and Solid PVC pipes.
But how do foam core and solid PVC pipe compare? Both PVC products can be used over ground and underground, with few adjustments for the foam core PVC. The two differ in size, cost, weight, thickness, and load capabilities. The solid PVC pipe is better in all of the mentioned qualities, except for cost.
The article covers more information on foam core and solid PVC pipes, explaining what they are, their differences, and their similarities. Read on to learn which one you should get for your next project.
Understanding Foam Core and Solid PVC Pipe
Solid PVC Pipe
A solid Polyvinyl Chloride pipe is a plastic pipe with varying diameters and wall thicknesses. This pipe is made by heating and melting the raw material and extruding it to match the desired shape. After cooling, the results are a solid PVC pipe which is then cut to desired lengths.
PVC pipes have been available for over eight decades for most plumbing work. The pipes are used for the supply of water in buildings and irrigation. They are also used in drain, waste, and vent systems, commonly called DWV systems.
Foam Core PVC Pipe:
A Foam core PVC pipe, also called schedule 40 PVC cellular core pipe. This is a PVC product that includes a foam layer between thin outer and inner parts of the pipe walls. These two parts work as skin, protecting the foam in between, which is also non-porous.
The foam core PVC has been around since 1979, the year it was developed by Alphacan, a pipe company in France. This pipe is used in most projects that solid PVC is used in but is limited to low-pressure projects. Both PVC products meet the ASTM standards, which most schedule 40 pipes must meet for various qualities, like material and extrusion quality.
Foam Core Vs. Solid PVC Pipe Differences
Foam core and solid PVC pipes have differences in many ways. The core differences are as follows.
Structural
One of the differences between foam core and solid PVC pipes is how they are manufactured. Solid PVC pipe is all solid around its walls, while the foam core pipe contains the foam layer between thin outer and inner walls.
Run your finger along the edge of the foam core PVC pipe to feel the varying textures between the core and the walls.
Strength
Solid and foam core PVC pipes vary in strength, with the solid core PVC being sturdier than the foam core pipe. The foam layer between the pipe reduces its strength and can handle lower pressure than the solid option.
A Solid schedule 40 PVC can handle the pressure between 130 and 810 PSI, depending on the nominal pipe size.
Cost
Foam PVC pipes are significantly cheaper than solid ones, which is one of the reasons manufacturers engineered them. They are an affordable solution for contractors and people building houses on a budget.
A 4-inch X 10-ft Charlotte pipe schedule 40 solid PVC price is $43.47 on home depot. The same size and length Charlotte pipe foam-core PVC costs $31.00, almost 30% less than a solid PVC pipe.
Weight
The foam core pipe weighs less than the solid pipe, mainly because of the lighter materials in the interior core of the pipe. On the other hand, the solid option is all firm, which increases its weight.
A 4-inch X 10-ft Charlotte pipe schedule 40 solid PVC weighs 20.12 lbs., while the same size and length foam core weighs 14.6 lbs.
Load Capability
While both types can be used in most plumbing operations, solid PVC is often the favorite because it’s stronger. The latter has better load capabilities, especially on small-diameter pipes, six inches and lower.
However, the foamed layer in the foam core PVC pipe absorbs pressure from the surroundings, making it stress-free. This prevents damage to the pipes, a common problem with some solid PVC pipes used underground.
Damage Risk
The stronger solid PVC pipe is also less susceptible to damage during installation and maintenance. On the contrary, the thin skins on the outer and inner parts of the foam core pipe can easily snap and get damaged during installation. Damages on this PVC product can result in leakages in the pipes shortly after installation.
In facilities where mechanical pipe cleaning is regular, the foam core pipe risks getting damaged after some time. The mechanical devices used include the snakehead and plumbing auger bits that can wear down the thin inside wall of the pipe. The foam core is then exposed, and the pipe begins to leak.
Thickness
Foam core PVC pipes are manufactured as schedule 40, which has a thickness of 0.154 inches on the two-inch nominal pipe. Solid PVC pipes can be manufactured in schedule 80, which has thicker walls with over 0.218 on the 2-inch nominal pipe. The extra thickness allows it to be used in industrial piping systems.
Foam Core Vs. Solid PVC Pipe Similarities
While foam core and solid PVC pipes have many differences, they also share similarities. Among them are;
Temperature Capabilities
Since foam core and solid PVC pipe use the same compound during manufacturing, their temperature capabilities are the same. They operate at temperatures under 140° F (60° C), which is also their maximum operating temperature.
Installation Process
Both PVC products use the same process during installation, from preparation, like cutting and joining, and take almost the same time to cure. They both require the same support when installed over the ground. However, few constructors say that installing foam core PVC pipe is easier.
The foam core pipe can also be installed underground, like the solid PVC pipe. However, professionals advise using a wider trench than the pipe. Also, cushion the pipe from pressure by adding sand around it.
Related Questions
Following are the frequently asked questions related to the foam core and solid PVC pipes.
Use the foam core if you’re on a tight budget and need PVC pipe for a regular building DWV system. However, check with the building inspection department in your area because some discourage their use. However, if budget is not your concern, use the stronger and more durable solid PVC pipe.
The foam core PVC pipe has better noise reduction properties than the solid PVC pipe. The foam between the pipe absorbs sound from within, like when water flows down, reducing noise. However, some people claim not to notice the noise reduction and say it works the same as solid PVC pipe.
Pipework in an industrial or manufacturing facility requires a pipe that can handle high pressure, which the foam core PVC pipe can’t. The thin PVC layers covering the foam core can also be worn out fast by chemicals, damaging it.
Bottom Line
While foam core and solid PVC pipes are used in most residential plumbing and irrigation, they have several differences and similarities. The solid PVC pipe edges in almost everything, with only a few demerits, like their cost. The two PVC products share almost similar installation processes and temperature capabilities.
When choosing between the two pipes, you can base your decision on cost and pick foam core PVC pipe. However, if cost is not your concern, use a solid PVC pipe for more lifespan and better pressure capabilities.