Joining copper pipes is a crucial skill for any do-it-yourselfer or professional working with plumbing systems. Traditionally, copper pipes are joined together by soldering. But did you know there are several methods to glue copper pipes to create strong, leak-free bonds without ever firing up a torch?
Why Glue Copper Pipes?
Sweating copper fittings is the tried-and-true method that most plumbers rely on. But soldering requires an open flame, flux, and other specialized tools. It can also be challenging in tight spaces or areas where an open flame is risky.
Gluing offers several advantages when joining copper:
- No open flames – Glues cure safely without dangerous torches.
- Faster connections – Adhesives set up quicker than soldering.
- Tighter spaces – Easier to glue pipes in cramped areas.
- Limited tools – Basic supplies like glue and emery cloth are all you need.
- Permanent bonds – Strong epoxy adhesives last as long as soldering.
For these reasons, gluing is the preferred method for DIYers making simple repairs. But even professionals use adhesives for certain applications, like connecting pipes in attics or crawl spaces. The key is selecting the right glue and using proper procedures to create leak-free joints.
Can You Use Super Glue on Copper Pipes?
One option is using cyanoacrylate adhesives, better known as “super glues”, to bond copper plumbing. Loctite and Krazy Glue are popular brands of cyanoacrylate glue. But how well do these one-part glues work on metal pipes?
Super glues can bond copper effectively for small repairs if used properly. Their fast-curing formula chemically fuses to copper surfaces in seconds. However, cyanoacrylates have some disadvantages compared to two-part epoxy adhesives:
- Lower heat resistance – Super glues can fail at temperatures above 200°F.
- Not as strong – Epoxies form stronger, more rigid bonds long-term.
- For small repairs – Super glues lack gap-filling abilities for larger joints.
Cyanoacrylates work best for gluing small copper fittings like couplings and caps in low-temperature applications. They can quickly patch pinhole leaks or seal small damaged sections. Just ensure surfaces are clean before applying a thin layer of super glue and holding parts tightly together.
Super glues like Krazy Glue can quickly form bonds between copper surfaces. But epoxy adhesives are better for high-strength, permanent joints.
Using Epoxy to Glue Copper Piping
For maximum strength and heat resistance, two-part epoxy adhesives are the best choice for permanently joining copper plumbing. Epoxies create rigid, long-lasting bonds stronger than soldering.
Here are some top epoxy products for gluing copper pipe:
- J-B Weld – Steel-reinforced epoxy with 500°F temperature resistance.
- Gorilla Epoxy – Versatile glue ideal for indoor and outdoor plumbing.
- Loctite Epoxy – Plastic-bonded formula cures slowly to prevent drips.
- PC Products PC-7 – Low-odor epoxy designed for potable water systems.
Follow these basic steps to properly epoxy glue copper pipes:
- Sand and clean bonding surfaces – Remove any coatings or oils from pipe ends using emery cloth or sandpaper. Wipe clean with isopropyl alcohol.
- Mix epoxy – Combine equal parts resin and hardener according to manufacturer instructions. Stir thoroughly until uniform color.
- Apply epoxy – Spread a thin, even layer of epoxy on both bonding surfaces.
- Join and rotate pipe – Mate the prepared pipe ends, then slowly rotate pipe to distribute epoxy evenly.
- Support and allow curing – Use clamps or tape to hold pipes together firmly. Allow adhesive to fully cure based on instructions, often 24 hours.
Epoxy adhesives like J-B Weld are excellent for permanently joining copper plumbing. Just ensure surfaces are prepped and parts are aligned before glue cures.
Pro tip: For added strength, rough up bonding surfaces with 60-80 grit sandpaper before applying epoxy. The scratches give the glue something extra to grip.
Can You Use PVC Glue on Copper Pipes?
Do not use PVC cement to attempt gluing copper pipe. This solvent cement is only formulated to bond PVC plastic pipes and fittings. PVC cement is not compatible with copper surfaces.
PVC glue contains tetrahydrofuran (THF), a solvent that melts and fuses PVC materials only. It will not create any bond with metal pipes. Solvents can also damage or weaken copper.
Leave PVC glues for plastic plumbing only. Use cyanoacrylates or epoxies specially designed for gluing metals like copper. Matching the adhesive to your pipe material is essential.
Solderless Copper Pipe Connections
Another method for joining copper plumbing without soldering is using solderless bonding solutions. These liquids create permanent seals by chemically fusing to copper oxide surfaces.
Popular solderless copper bonding products include:
- RectorSeal Copper Bond – Applies like paint for easy sealing.
- Gripple AquaBloc – Flexible seal for frequent pipe movement.
- Elkhart X-TruBond – Gel formula ideal for overhead applications.
To use these products:
- Clean and sand pipe surfaces to expose fresh copper.
- Apply bonding agent according to directions.
- Mate parts within open time of product. Apply steady pressure.
- Allow full cure time before introducing water pressure.
Solderless agents provide quick, low-mess seals for copper repairs. But epoxy adhesives tend to have greater shear strength after curing. Consider both options when soldering is not possible.
Can You Use Push-Fittings on Copper?
Push-fit or press-fit copper fittings provide a solderless alternative for connecting pipes. These mechanical fittings use O-rings or grip rings to seal and hold pipes in place.
Common push-fit fitting systems for copper plumbing include:
- SharkBite – Push-to-connect fittings ideal for DIY repairs.
- ProPress – Press-style copper fittings using proprietary crimping tools.
- PEX – Can adapt to copper male adapters for hybrid systems.
Benefits of push-fit copper connections:
- Super-fast installations.
- No glues, soldering, or curing.
- Flexible for repairs and additions to existing piping.
- Allows disassembly and repositioning.
Just insert cleaned, deburred copper pipes fully into fittings and they lock securely in place. Push-fittings are reliable for most low-pressure residential and commercial plumbing applications.!
Push-fit or press-fit copper connections offer a fast, flame-free alternative to soldering. They can adapt to existing copper piping for easy repairs.
Gluing Copper Pipes vs. Soldering
How does gluing copper compare to soldering in terms of strength, longevity, and ease of use? Here’s a quick breakdown:
| Method | Bond Strength | Heat Resistance | Ease of Use | Ideal Applications |
| Soldering | Very strong | High, 500°F+ | Moderate learning curve | Most copper plumbing |
| Epoxy | Very strong | Up to 500°F | Easy for DIYers | Repairs, tight spaces |
| Super Glue | Moderate | Up to 200°F | Very easy | Small repairs only |
| Push-Fittings | Moderate | High | Extremely easy | Repairs, retrofits |
For most applications, a properly soldered joint remains the preferred method by plumbers. But gluing and push-fittings excel in situations where soldering is difficult or unsafe. Combined with their ease of use, this flexibility makes adhesive copper connections a handy technique for DIYers and pros alike.
Gluing Copper Pipe: Step-By-Step
Follow these best practices when gluing copper pipes for a safe, reliable bond:
1. Gather Supplies
- Copper pipe & fittings
- Emery cloth
- Acetone or alcohol
- Rags
- Adhesive (epoxy or cyanoacrylate)
- Applicator brushes
- Clamps or tape
2. Prep Pipe Ends
- Cut pipe squarely with tubing cutter
- Deburr ends with a file or knife
- Sand 1-2” of surface with emery cloth
- Wipe clean with acetone/alcohol
3. Apply Adhesive
- Mix and apply epoxy as directed
- Or apply thin layer of cyanoacrylate
4. Join and Hold Pipes
- Insert pipe fully into fittings
- Slowly rotate pipe to distribute glue evenly
- Use tape or clamps to hold joints tightly
5. Allow Proper Cure Time
- Don’t disturb joint while adhesive sets
- Full bond strength takes 24 hours for epoxy![Step-by-step guide to gluing copper pipes together using epoxy][]
Follow key steps like surface prep, applying adhesive, and proper curing when gluing copper plumbing for reliable results.
Tips for Gluing Copper Pipes
Gluing copper plumbing may take some practice to master. Keep these tips in mind for success:
- Match pipe sizes – Adhesive joints require tight fits. Never try to glue mismatched pipe sizes.
- Use proper solvents – Clean only with compatible solvents like alcohol or acetone to avoid corrosion.
- Avoid drips – Carefully apply adhesive in thin, even layers to prevent messy drips.
- Align properly – Insert pipes fully and align at proper angles before adhesive sets.
- Brace joints – Use tape, clamps, or fittings to hold pipes in position while glue cures.
- Allow full cure – Do not pressure test joints or introduce water before adhesive has fully hardened.
- Conduct leak tests – Check for leaks using air or water testing once glue has completely cured.
Proper preparation and following the adhesive manufacturer’s directions are crucial to create strong, leak-free bonds gluing copper plumbing. But the results are well worth the extra effort compared to soldering.
Frequently Asked Questions
Is gluing copper pipe permanent?
Copper pipes joined with epoxy adhesives will last permanently if bonded correctly. Epoxy-glued joints can be as strong as soldering when surfaces are prepped and parts are properly aligned during cure time.
What is the strongest glue for copper?
Two-part epoxy adhesives provide the strongest bond for gluing copper plumbing. Look for epoxies formulated for metal that cure rigidly. This provides maximum strength to resist high pressures and temperatures over decades of use.
Can you JB Weld copper pipes?
Yes, JB Weld is an excellent epoxy for bonding copper pipes. The steel-reinforced formula makes it extra strong for high-pressure systems. As with any adhesive, proper surface prep and application is key for reliable copper pipe repairs.
Is soldering copper pipes better than glue?
For most applications, soldering remains a preferred method by professionals. But gluing with epoxy or using push-fittings can actually produce bonds just as strong as soldering. This makes gluing a great option for DIYers or situations where soldering is difficult.
Is glue better than soldering copper?
Gluing has advantages over soldering copper in certain situations:
- No open flames required
- Faster connections with quick-set adhesives
- Easier repairs in tight spaces
- Requires fewer specialized tools
So while soldering may be better for extensive plumbing, gluing excels for simpler copper repairs and projects.
Conclusion
While soldering is still the go-to technique for sweating copper fittings, gluing copper pipe offers many advantages. Epoxy adhesives produce super-strong bonds that can last a lifetime. Cyanoacrylates like super glue provide quick repairs for small leaks and damage. And push-fittings allow flame-free assembly with no curing required.