What can I use to plug PVC pipe?

When it comes to fixing or patching PVC pipes, you have several options for plugging or sealing small holes or cracks. Some effective ways to plug PVC pipe include using PVC cement, epoxy putty, silicone sealant, threaded PVC caps, rubber stoppers, and freeze plugs.

PVC Cement

One of the most common and effective ways to plug a PVC pipe is by using PVC cement. This is the same cement used for joining and assembling PVC pipe connections. PVC cement works by dissolving the surfaces of the PVC and welding them together to create a watertight seal.

To use PVC cement to plug a hole or crack in a pipe:

Make sure the area you want to plug is clean and dry
Apply a liberal coat of PVC cement to the inside of the hole and the pipe surface around it
Quickly press a piece of scrap PVC pipe into the hole, twisting it to spread the cement

Hold for 30 seconds until set

The PVC cement will fuse the scrap pipe in place to plug the hole. If the hole is very small, you can simply use a PVC cement dauber applicator to fill it with cement and smooth over the surface.

Advantages of PVC Cement

Creates a permanent, waterproof seal

Used for assembling all PVC joints already
Inexpensive and readily available

Disadvantages of PVC Cement

Can only be used on PVC pipes

Permanent – cannot be easily removed or undone
Will not work on wet or actively leaking pipes

Epoxy Putty

Another option for plugging small holes in PVC pipe is using epoxy putty. This is a two-part putty that is mixed together to create a permanent seal.

To use epoxy putty:

Clean and dry the area to be repaired thoroughly
Mix equal parts of the putty resin and hardener together until uniform color

Roll the putty into a “snake” and wrap it around the pipe, pressing it into the hole
Continue smoothing and shaping the putty until the hole is fully sealed
Allow at least 30 minutes to fully cure before disturbing

Epoxy putty makes a complete seal and will bond to PVC, metal, plastic, concrete, fiberglass and more. It can be sanded or painted over after curing.

Advantages of Epoxy Putty

Will seal both dry and wet/leaking pipes
Can be molded or shaped as needed

Bonds to many materials including PVC
Permanent seal once cured

Disadvantages of Epoxy Putty

Has limited workable time once mixed

Surface needs to be cleaned and dried first
Takes 30+ minutes to fully cure

Silicone Sealant

Silicone sealant or silicone caulk can also be used as a quick way to plug holes and cracks in PVC pipe. Silicone will remain flexible after curing and can seal both dry and wet surfaces.

To use silicone on PVC pipe:

Clean area thoroughly and remove any water or moisture
Apply silicone sealant or caulk generously over the hole, smoothing with a finger or tool

Allow to cure for several hours until no longer tacky

For best results, you may need to allow silicone to cure for 24 hours before disturbing the sealed pipe.

Advantages of Silicone

Seals both dry and wet surfaces

Stays flexible after curing
Quick and easy application
Can seal a wide variety of materials

Disadvantages of Silicone

Does not bond as strongly to PVC compared to other options
May not maintain a seal on high pressure systems
Can dry out and crack over time

Threaded PVC Caps

For larger holes or a clean open end of cut PVC pipe, a PVC cap can be used. PVC caps screw on and make a tight seal on threaded PVC pipes.

To use a threaded PVC cap:

Ensure pipe end is threaded and clean

Select a cap of the corresponding PVC size and thread type
Apply PVC cement or pipe sealant to the threads
Screw cap on tightly until a complete seal is made

Threaded PVC caps provide a quick mechanical seal and are easy to remove later if needed. They are available for all common PVC pipe thread sizes.

Advantages of Threaded PVC Caps

Mechanical seal – no curing time
Can be easily removed

Available in all PVC thread sizes

Disadvantages of Threaded PVC Caps

Only works on threaded PVC pipe
May not make as tight a seal as cements or epoxies

Can vibrate loose over time

Rubber Stoppers

Rubber stoppers provide a quick way to plug holes and gaps in PVC pipe systems. They simply press or wedge into an opening to create a tight friction fit seal.

To use a rubber stopper:

Select a stopper slightly larger than the hole
Make sure the area is clean and dry
Press the stopper in firmly until it seals the opening

Rubber stoppers come in a variety of common PVC sizes and can be cut or trimmed as needed. They work well for capping pipe ends or sealing damage during temporary repairs.

Advantages of Rubber Stoppers

Quick and easy to install
Tight friction seal

Low cost
Available in many sizes

Disadvantages of Rubber Stoppers

Seal may not last on high pressure systems

Can fall out or dislodge over time
May not make a watertight seal on leaks

Freeze Plugs

In a pinch, you can also use a freeze plug to temporarily seal a leaking PVC pipe. This involves plugging the hole with an object of similar size, packing ice around it, then sealing the area with tape.

To implement a freeze plug:

Clean area thoroughly and dry as much as possible
Pack plumber’s putty, epoxy putty or similar around pipe hole

Fill surrounding area with ice cubes or shaved/crushed ice
Wrap the entire area thoroughly with waterproof tape

As the ice melts, water pressure will force it into the putty or epoxy, sealing the leak. This provides a temporary plug until a more permanent repair can be made.

Advantages of a Freeze Plug

Can quickly stop an active leak
Uses simple, available materials
Doesn’t require permanent sealing products

Disadvantages of a Freeze Plug

Very temporary solution – ice will melt
May need to repack ice frequently
Doesn’t work as well on large holes

Choosing the Best Plug Method

Choosing the right way to plug or seal PVC pipes will depend on several factors:

Pipe size and details – is it threaded, belled end, schedule 40 etc.
Type of hole or opening – crack, clean hole, capped end etc.

Whether the pipe is actively leaking water
Desired permanence of the repair
Time and tools available

In most cases, PVC cement, epoxy putties or silicone provide reliable, permanent repairs for damaged PVC pipe. For quick, temporary fixes, rubber stoppers or freeze plugs may be suitable.

Threaded PVC caps can seal cut or open-ended pipe quickly. However, they don’t provide as tight a seal as bonded options on side holes or cracks.

Combining methods, like using rubber stoppers with silicone or epoxy around them, can improve the seal in some cases.

Safety Tips When Working With PVC Pipe

When making repairs to PVC plumbing pipes, keep these safety guidelines in mind:

Turn off water supply and drain pipes before starting work
Wear protective equipment like gloves and eye protection

Use proper ventilation when working with solvent glues and cements
Make sure there are no sources of ignition for flammable cements
Follow all manufacturer safety instructions

Exercise caution when cutting or sanding plastic pipes
Dispose of PVC cement and other products properly

When to Call a Professional

In some cases, it’s best to call in a plumbing professional to repair or seal PVC piping:

For large holes or splits in pipe
If the damaged pipe is in a wall or otherwise inaccessible
If you need to cut out and replace a section of pipe

For leaks or breaks in main water lines
If you’re uncertain about the best repair method
For additional help if your DIY fix doesn’t hold

A qualified plumber has the expertise to fully assess any PVC pipe damage and make lasting repairs you can rely on.

Conclusion

Sealing holes and leaks in PVC pipe doesn’t have to be a major production. With the right supplies and techniques, small cracks and damage can often be patched up quickly and easily. Just remember to always exercise proper safety precautions when working with plumbing systems.

The most common and effective ways to plug PVC pipe involve solvent welding products like PVC cement or epoxies. But in a pinch, stoppers, caps and even freeze plugs can temporarily stop leaks. Matching the best sealing method to the type and location of damage is key for successful repairs.

For severe leaks or complex repairs requiring significant pipe replacement, don’t hesitate to call in a professional plumber. They have the expertise to diagnose issues and implement lasting solutions. But for minor holes and cracks, a bit of PVC cement or epoxy putty can usually do the trick.