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Quick Answer
It is possible to attach PVC to ABS piping using the right materials and techniques. While PVC and ABS are not directly compatible for gluing, there are adapter fittings made specifically to join the two together. The key is using the correct cement and primer made for connecting ABS to PVC. With the right supplies and proper preparation, PVC and ABS pipes can be securely connected.
Background on PVC and ABS Pipes
PVC (polyvinyl chloride) and ABS (acrylonitrile butadiene styrene) are both widely used for residential drainage and sewer systems. They are inexpensive, easy to install, and durable. However, there are some key differences between the two:
| PVC | ABS |
|---|---|
| Made from polyvinyl chloride plastic | Made from acrylonitrile butadiene styrene plastic |
| White or off-white in color | Black in color |
| Rigid and can be brittle | More flexible and impact resistant |
| Better chemical resistance | Better at low temperatures |
The key difference between the two types of plastic piping is the material composition. This means PVC and ABS cannot be solvent welded together directly with cement. The glue or cement used for PVC is not compatible with ABS and vice versa.
However, even though the base plastic is different, PVC and ABS pipes can still be joined using the right adapter fittings and cements.
Can PVC and ABS Pipes Be Connected?
Yes, it is possible to connect PVC and ABS drainage pipes using specialty adapter fittings. These fittings are made to transition between the different plastics and are joined using a two-step process with primer and cement made specifically for PVC to ABS connections.
There are a few options for PVC-ABS adapter fittings:
– Mission couplings – These are straight connector fittings with a PVC end and an ABS end, allowing the two different pipes to be joined in a straight line.
– Mission bands – These flexible rubber couplings have stainless steel bands on the outside. They slide over the pipes and tighten down to create a sealed joint.
– Fernco couplings – Made from heavy-duty rubber, these flexible and protective sleeves slide over each pipe to connect them. The ribs and steel bands provide a tight seal.
– Harvel PVC-ABS transition couplings – This style has a PVC end, ABS end, and center sleeve that slides over the pipes. Stainless steel clamps tighten to seal the connection.
The mission and Harvel style couplings rely on solvent cement bonding just like standard PVC or ABS connections. The mission bands and Fernco styles use mechanical seals so no cement is required.
Using Mission Couplings
Mission style PVC to ABS transition couplings are a common and reliable way to connect the two different plastic pipes. Here are the steps involved:
1. Sand and clean the ends of the PVC and ABS pipes. This roughs and primes the surface.
2. Apply PVC-ABS transition primer to the ends of both pipes. This helps the cement adhere and bond.
3. Apply PVC-ABS transition cement to the inside of the mission coupling and the ends of the pipes.
4. Quickly insert the PVC and ABS pipe ends fully into the mission coupling while twisting to spread the cement.
5. Hold in place for 30 seconds to allow the initial bond to form.
6. Wipe away any excess cement and allow the joint to fully cure for at least 24 hours before pressure testing.
The mission coupling should create a permanent, watertight connection between the PVC and ABS pipes once fully cured. Be sure to only use cement and primer designed for joining PVC and ABS together, as regular PVC or ABS cement will not work.
Pros and Cons of Connecting PVC to ABS
Joining PVC to ABS piping comes with both advantages and disadvantages to consider:
Pros:
- Allows combining PVC and ABS within a drainage system
- Adapter fittings create a solid connection between the materials
- No need to replace existing pipes when renovating or expanding
- Transition couplings are inexpensive
Cons:
- More joints in the system that could potentially leak
- Transition joints may be more prone to root intrusion over time
- Needs proper primer and cement to make connections
- Additional labor for installation vs using all one material
In most cases, the ability to connect PVC and ABS outweighs the downsides. Having an integrated system avoids needing to replace all ABS or PVC pipes when alterations are required. Just be diligent with proper gluing techniques for reliable joints.
Tips for Connecting PVC to ABS
When joining PVC to ABS drainage pipes, follow these tips for success:
- Only use plastic transition fittings and rubber couplings specifically designed for PVC to ABS connections.
- Thoroughly clean and sand pipe ends to improve adhesion.
- Apply primer and use a Dauber style applicator for controlled cement application.
- Allow joints to cure fully for at least 24 hours before pressure testing.
- Stagger PVC-ABS joints offsets within the system.
- Support pipes with hangers near transition fittings to avoid shear stress.
- Test for leaks using air or water before covering connections.
Proper planning of the drainage layout and following the manufacturer’s instructions for installing transition couplings will result in secure, leak-free joints between PVC and ABS pipe systems.
PVC to ABS Transition Fittings
There are a few standard options when it comes to adapter fittings designed to join PVC and ABS pipes. Here are some of the top products:
Charlotte Pipe PVC-ABS Transition Couplings
Charlotte Pipe is a leading brand for plastic piping systems. Their PVC-ABS couplings provide a straight connection between the two pipe materials using solvent cement. Charlotte Pipe couplings come in a full range of standard drainage sizes.
Mission Rubber Flexible Coupler
Mission offers heavy-duty rubber PVC-ABS joining sleeves with stainless steel clamps in sizes from 1.5” to 6”. The flexible rubber construction allows these couplers to join pipes that aren’t perfectly aligned.
Fernco Proflex PVC-ABS Coupler
The Fernco Proflex series is designed to easily join PVC, ABS, or cast iron through a flexible rubber sleeve with stainless steel clamp bands. Available in sizes from 1.5” to 10”.
Harvel Clearflow PVC-ABS Coupling
Harvel makes a Clearflow line of plastic PVC-ABS sewer and drain adapters. The straight coupling has a center sleeve and stainless steel worm gear clamps for a tight fit. Sizes range from 1.5” to 6”.
These are just a few of the quality options for officially rated and code approved PVC-ABS transition fittings. Use the right product for your project and always follow the manufacturer’s instructions.
Conclusion
Joining PVC and ABS pipes is certainly possible with the use of proper adapter fittings. Mission style straight couplings work well for inline connections while Fernco and Mission rubber sleeves allow for some misalignment. Be sure to only use cement and primer made specifically for bonding PVC and ABS together. With the right supplies and proper technique, PVC and ABS plastic plumbing pipes can be combined to create an integrated drainage system.