You generally don't use plumber's tape (Teflon tape) on the main sink drain's threaded connections that use rubber gaskets or plumber's putty, as the gaskets and putty create the seal, but you do use it on threaded pipe joints (like connecting trap to pipe) if there are no gaskets or you need extra sealing for those specific water-carrying threads. Always check instructions, as tape can cause leaks if used incorrectly on gasketed areas or if you use too much, which can crack fittings.
Plumber's putty: a soft, malleable sealant used to form a watertight gasket between flat, non-porous surfaces (eg, drain flange to sink/tub surface). It fills small gaps and is removable.
Plumber's tape has many uses. It can make projects more manageable and help ensure pipes are sealed properly and watertight. It is a thin yet powerful tape that ensures pipe joints are easy to manipulate without compromising a strong connection. When choosing any tape, it is essential to understand how it works.
All fittings with a taper, flare or O-ring should never use teflon tape or sealant. Teflon or sealant will actually make a compression or O-ring fitting leak. The only type to use a sealant on is pipe thread to pipe thread. Pipe thread to O-ring swivel pipe do not use sealant.
The better substitute for plumber's tape (thread seal tape) is “pipe dope,” also known as pipe thread sealant or pipe joint compound. Thread paste is specifically designed to seal the threads of a pipe and is known to be better for maintaining a permanent steal than Teflon plumber's tape.
Step 4: How many times the thread seal tape will go around the pipe depends on the thickness of the tape, but for the standard variety, about five or six wraps should be enough for the job.
Silicone Plumbers Tape
Just like with pipe thread tape, you can use it on all metal, rubber or plastic pipes. If you've noticed a leak in your pipe, you can apply this tape to the affected area. Because the tape is very strong, it should seal the leak immediately. However, this is not a long-term solution.
Sealing is an essential part of sink drain installation and maintenance because it keeps everything watertight. However, even the strongest sealant doesn't last forever. Over time, leaks and drips can become a problem.
How To Install A Kitchen Sink Drain Pipe
Drain leak
One common reason we see water leaking from a sink drain is due to old, worn-out plumber's putty that fails to provide a long-lasting, watertight seal. This is particularly true if the sink has been in use for many years. Over time this putty starts to thin, dry out or even crack, causing leaks.
Without an air gap, there's a slight risk of wastewater backflow into the RO system if your sink drain gets clogged. Regular maintenance of your drain can mitigate this risk.
Improper Application of Teflon Tape Wrong direction: If the tape is wrapped counter to the thread direction, it unravels when tightened. Too little tape: Less than 2–3 wraps may not seal properly. Too much tape: Overwrapping can prevent proper thread engagement or even crack fittings.
Putty is for sink drains. Pipe dope is for metal fittings, typically gas applications. Stick with teflon tape for everything else. PVC, CPVC, ABS or any plastic type fittings should only require pipe dope.
Commonly used for sealing threaded connections in pipes, valves, and fittings, plumber's tape is effective for water, gas, and air lines. It prevents leaks and guarantees a secure seal.
What NOT to put down your drain or flush down the toilet:
The 135 rule of plumbing refers to the placement of drain line cleanouts, which are used to clear any clogs and keep the drains functional. According to the 135 degree rule of plumbing, a cleanout must be present every 100 feet of drainage line and for each cumulative change in pipe direction that exceeds 135 degrees.
It is important not to overwrap your pipe — too much thickness can prevent a tight seal — so stick with three full rotations to start. Step 6: Rip or cut the tape when you are done and use your fingertips to smooth the edges of the tape firmly to the pipe.