How to Glue PVC Pipes Together So They’re Watertight

When it comes to plumbing, tight connections between pipes are crucial. Without the right bond, you could have leaks, flooding, and water damage in a home. Thankfully, joining PVC plastic pipes is simple and fast as long as you’re accurate and use the right glue, tools, and techniques. This guide will walk you through how to glue PVC pipes and help you avoid common mistakes.

Why You Should Use Glue to Connect PVC Pipe for Plumbing

While PVC pipes can fit together without glue, gluing them is the key to a permanent leak-free seal. PVC solvent cures quickly and creates a strong hold between pipes and fittings that can only be broken by sawing the pipes.

Is There a Specific Type of Glue to Use?

The glue used to connect PVC piping and fittings is highly specific. It doesn't work like ordinary adhesive, and is better thought of as a chemical solvent. It works by melting the surface of the PVC, then quickly hardening to fuse attached pieces with an airtight, seamless, leakproof bond. The results are similar to welded metal.

It's important to pick the proper solvent for PVC pipe. Carefully read product labels and avoid universal solvent cements. Some popular brands that make PVC solvent include Oatey, Weld-On, and Gorilla, though you'll find others at your local hardware store or home improvement center.

For a reliable seal, you'll need to use a primer with your PVC solvent. Purple primer is usually required by building codes. The bright color allows inspectors to see that all fittings have been primed.

Tools Needed to Glue PVC Pipe

In addition to the solvent cement and purple primer, you'll need a few tools to glue PVC pipe.

Solvent cements are dangerous, so avoid eye or skin contact. Wear safety goggles with side shields and protective gloves as you work. An organic vapor respirator can protect you from breathing in harmful solvent vapors. You can also lay a tarp or towel to protect your workspace and use rags to wipe up accidental drips.

The tools you'll need include a fine tooth handsaw or ripsaw to cut lengths of PVC pipe to fit, an 80-grit sandpaper to deburr the cuts you make to each pipe, and a felt-tip marker to mark cuts and connections.

Gluing PVC Pipe Together: A Step-by-Step Process

Follow these simple steps to glue a PVC pipe to a compatible fitting.

1. Measure and Cut the Pipe(s)

Gluing PVC pipe together starts with knowing how to cut PVC pipe. You'll want to ensure that each length of pipe sits fully in its fittings. For accurate sizing, measure the distance between shoulders on the fittings at each end of your pipe. Transfer that measurement to the pipe with a felt-tip marker.

With your pipe on a level surface, use your hacksaw to make a straight, square cut. Square pipe ends fit snugly into fittings with plenty of contact area for solvent cement to work properly. They also make for an even interior surface that water can flow through smoothly.

Once your pipes are cut, use 80-grit sandpaper to scrape the inside and outside of each cut smooth. This removes burrs that would otherwise snag debris such as hair and cause clogs.

2. Test How the Pipe(s) Fit Together (Without Glue)

Plumbing needs to fit together perfectly to ensure a leak-free seal, so take time to dry-fit all connections before gluing anything together. Lay out all pieces to make sure that they fit together nicely and are cut to the correct length.

PVC glue dries fast, and you'll only have a few seconds to put the pipes together when it's applied. Before you take apart your dry-fit assembly, make reference marks and number each connection so you can quickly put everything back in place when it's time.

3. Prime the Ends of the Pipes

Primer softens and cleans the plastic so that the glue can work properly. You'll need to use purple primer so that it's visible for inspectors. Shake the can of primer for about 30 seconds to mix the solution. Open it and wipe any excess primer on the lid so it doesn't drip.

Take your first fitting and spread primer over the outside of the pipe's end. Spread enough so the primer will overlap the fitting collar the pipe is going into. Spread the same amount of primer on the inside of the pipe fitting collar. Give the pipe and fitting about 10 seconds to cure before applying any glue.

4. Apply Glue Over the Primer

Next, you'll apply glue in the same way you applied the primer. Apply an even amount over each surface. Once your glue is applied, you'll only have a few seconds for the next step before it starts to dry and cure.

5. Push the Pipes Together and Let the Cement Set

Immediately insert your pipe into the matching fitting and rotate them a quarter turn to line up your reference marks. Twisting the fitting slightly helps spread the cement evenly for a solid joint connection. Press and hold the pipe and fitting together for about 15 seconds so the glue doesn't push the pipe out of the fitting.

Consult your glue's manufacturer instructions for information about how long you need to wait before handling the connected PVC. Repeat these steps to attach any remaining pipe connections for your project.

Do You Need to Prime PVC Pipe Before Gluing?

Primer is essential when gluing PVC pipe because it creates a chemical reaction that softens the plastic and allows for better adhesion. Because gluing PVC pipe creates a chemical change—unlike other gluing projects that adhere two surfaces together—primer ensures the job is done right with a tight seal.

Can You Connect PVC Pipe Without Glue?

If you want to avoid the mess of cement and primer, there are ways to connect PVC pipe without using glue. However, if you want to transport water, any other liquid, or gas, your options are limited. Cement is typically required to carry fluids, though it means the only way to disassemble your pipes is by sawing them apart.

One alternative to glue is the use of PVC push-on fittings, which are fitted with rubber O-rings. These provide a strong enough connection to transport water safely.

If you don't need to transport a liquid or gas, you can simply push your PVC parts together. Compatible parts will fit snugly and won't come apart without outside pressure. This is useful if you need a connection that you can easily take apart.

Is Gluing PVC Pipe Together a DIY Project? 

Gluing PVC pipe together is a straightforward process. If you have your assembly planned out with everything cut to size and clearly marked, all it takes is quick and accurate handiwork to get everything adhered properly.

That said, if you’re attempting to glue pipes to avoid the cost of pipe replacement, consider the potential cost of water damage if those DIY repairs go wrong.

When to Hire a Plumbing Professional

While gluing PVC pipe together can be simple, plumbing projects are complex. Mistakes in any work that affects the flow of water through your home can be dangerous. If your home’s plumbing needs major repairs, it’s always best to call a plumbing repair service near you. Plumbers carry liability insurance and their work may be covered by your homeowner’s insurance.