There are many ways to connect PVC pipes, but it is important to find out which method works best for you. Depending on the method you choose, you can create a temporary connection or literally tie the PVC pipe.
Appropriate connection methods differ depending on your project and what you have on hand. In this article, we look at the basics of making a durable connection, how fittings improve your connection, and the different ways to join PVC pipes.
Useful tools for connecting PVC pipes
When connecting PVC pipes, make sure you have basic pipe-treating tools on hand. This includes:
- A pipe cutter (or a saw suitable for cutting pipes)
- Sandpaper or a utility knife (for treating post-cut burrs)
- A marker (to mark the joints)
- rags (for cleaning up drips or spills)
- Additional pipe
- Your login method of choice
Make sure you have a basic understanding of the connections you need to make and what they need to withstand.
Tips and safety for connecting PVC pipes
It’s a good idea to have extra pipes and fittings on hand in case you make a mistake when cutting the pipe or making the connections. This is especially important with more permanent methods such as solvents.
Clean the PVC before making the connection, even with push-in or threaded connections. A PVC cleaner works well for dirt, dust and grime, and 80-grit sandpaper can rid the pipe of burrs that cause clogging and interfere with tight connections.
If you use solvents, be sure to protect your skin and work area. Ventilate the area as much as possible and wear protective equipment such as a fan, safety glasses and gloves.
Basic elements of PVC fittings
PVC fittings are used to connect pieces of pipe together. There are several types that allow you to do things like:
- Attach two pipes to create a longer pipe
- Change the direction of your PVC
- Make fast connections
PVC fittings are coming standard sizes that fit perfectly around your PVC and you need to choose the right diameter for an efficient connection. While PVC fittings can hold your pipe in place, the pipe joint is not water safe.
Quality furniture vs. ordinary PVC fittings
Like PVC pipes, fittings come in furniture and standard varieties.
Furniture PVC is more resistant to sun damage and degradation, so it is less likely to change when exposed to UV radiation. It is also more impact resistant and there are no markings on the outside of the fittings.
If you are connecting PVC that will be exposed or sit outside, choose furniture quality fittings.
Types of PVC fittings
Are many varieties of fittings which offer different types of connections and allow you to achieve different angles with your PVC.
Some of the more common ones include:
- Adapters: also known as reducing couplings; change the end type of the PVC pipe to fit different sizes and types of PVC
- Bushings: usually threaded; mainly used for connecting PVC pipes with different connectors by reduction
- Caps and plugs: stop flow in a pipe (caps at the end of the pipe and plugs inside other fittings); Plugs usually have either a head or a male threaded end
- Couplings: connect two pipes together in a straight line; some reduce to connect small and large pipes
- Crosses: form a «plus»; useful in creating the framework
- Elbows: they come in different angles; allow you to route pipe around objects; side elbows have three ends to create corners
- Flanges: allow you to connect the PVC to items other than PVC (ie the base of a toilet); it resembles a disc and creates a seal between the object and the PVC
- Nipples: fitting with two male threaded ends used to connect two female threaded ends
- Unions: not as permanent as couplings; features a ring for easy deconstruction; often used in temporary constructions
- T-shirts: «T» shaped with two ends in a straight line and a third on the side; allow you to split a line in two with a perpendicular connection (or connect two into one)
Most PVC connections use a fitting of some sort. Your fitting and the intended use of your project affect the method you use to connect the PVC pipe.
Methods of connecting PVC pipes
The most common and effective methods of connecting PVC pipes include:
The first 4 work with standard fittings, but you need special mounting styles for the last 3 methods. Since some methods do not create a tight seal, this is important choose the right method for your project.
1. Dry mounting
Dry fitting is the easiest way to connect PVC pipe, but you shouldn’t rely on it as a permanent solution. To do this, simply push the PVC pipe into the fitting.
While PVC pipe sits snugly in appropriately sized fittings, a dry fit will retract over time, especially when under pressure.
We recommend that you fit the PVC before more permanent connection methods and label your connections. This is often your last chance to make quick and easy fixes.
2. Fasteners
Another method of temporary connection involves the use of fasteners such as screws. This is not nearly as strong as other methods and damages the integrity of your PVC, but the fasteners allow you to connect the PVC with little fuss.
To do this, fit the material as tightly as possible. Use a suitable drill bit to make a pilot in the PVC and fitting, then insert a self-tapping screw into this pilot hole.
The screw will hold everything together, but this connection method has a greater risk of loosening over time.
3. Silicone and glue
Common adhesives such as silicone and glue hold up well for low-impact projects, but can retreat over time. You cannot use silicone or glue to hold connections that carry water or steam.
If you plan to use silicone or glue to connect the PVC pipe, first use a PVC cleaner on the inside of the fitting and the outside of the pipe. You may also want to sand the bonding surfaces to improve the connection.
Apply the glue on a surface, then fit the PVC pipe into the fitting. Hold it in place long enough to let the adhesive set for the recommended time (preferably longer).
It is possible that the silicone or glue will recede over time, but the combination with the fixing method can help. For more permanent connections and less fuss, consider using a specialty solvent to connect your PVC.
4. PVC Solvents/ PVC Cement
Most connections require a PVC solvent (such as PVC glue or PVC cement) that melts the surface of the pipe and fitting to join the pieces together permanently. If you plan to connect PVC for plumbing, this is what you need.
Be sure to remove any burrs before using a PVC solvent. These can cause clogging in the drain pipes and can interfere with the outside connection and you can’t just try again if the burrs cause the connection to fail.
Brush the surface with a PVC primer before going in with the solvent. The primer cleans your pvc, softens the surface and serves as a visual indicator of its use (for inspection purposes).
Apply the solvent, then insert the PVC pipe into the fitting. Gently twist the pipe, then hold it inside the fitting for at least 15 seconds to prevent it from backing out.
Allow at least 20 minutes for the solvent to harden before further handling.
5. Flexible couplings
Flexible couplings, such as those of Fernco, allow you to connect PVC pipes without permanently welding the pieces together. They are not approved for all applications, but flexible couplings create effective seals and strong grips.
Flexible couplings use strong steel band clamps to hold the rubber tightly around the PVC pipe.
To make the connection, insert the PVC pipe into the flexible coupling and seat it firmly. Tighten the clamp to create a seal and prevent the pipe from backing out.
6. Push-On fittings for PVC
Push-on fittings are of a special type of connector which prevents the need for glue or welding. Instead, they have a ring with spurs inside that enhance the bond.
This is a permanent connection type. Once you’ve inserted the PVC inside the fitting, you’ll need a hacksaw to separate the pieces.
Press fittings are an excellent choice for quick fixes in certain systems. They have an O-ring to create a tight seal and you can use them in most concealed applications.
This usually comes down to what you feel comfortable using to connect the PVC for your project.
7. Threaded PVC pipes
PVC threaded pipe and fittings are another option for those who don’t want to deal with solvents or permanent connections.
Threaded connections have lower pressure ratings and a higher reputation for failure. Proper splicing of threaded PVC is essential for strong connections.
Clean the PVC pipe and fitting with a strong PVC cleaner, then apply a specially designed PVC thread sealant. Once applied, insert the pipe into the fight and backtrack until it’s gone.
You can use a wrench to extend the connection, but be sure not to over tighten. This can cause cracks that lead to leaks.
Conclusion
Make sure you use a connection method that suits your project and experience. When possible, focus on more permanent methods to create strong connections.
Remember to:
- Install your dry pipe before making any permanent decisions
- Remove burrs and clean the PVC
- Follow the instructions specific to the materials you are using
Comment below with any questions, tips, or tricks you have about connecting PVC pipes!
