Teflon tape, also known as PTFE tape, is an important tool used by plumbers, electricians, HVAC technicians, and DIYers for sealing threaded pipe connections. It helps prevent leaks by filling the small gaps between the male and female threads. Teflon tape comes in a variety of colors, but white and yellow are the most common.
While white and yellow Teflon tape may look different, they are actually the same product. The color does not affect the tape’s ability to seal and lubricate threaded connections. The main difference between white and yellow Teflon tape is visibility – yellow makes it easier to see the tape on the threads during application.
In this article, we will take a deeper look at white and yellow Teflon tape and discuss:
- What is Teflon tape?
- The properties and uses of Teflon tape
- Differences between white and yellow Teflon tape
- When to use white vs. yellow Teflon tape
- Proper application of Teflon tape
Let’s start by understanding exactly what Teflon tape is and why it is so useful for plumbers and DIYers.
What is Teflon Tape?
Teflon tape, also referred to as PTFE tape, is a thin, non-adhesive tape made of polytetrafluoroethylene (PTFE). PTFE is a synthetic fluoropolymer that has an extremely low coefficient of friction, making it an excellent lubricant.
Here are some key properties and characteristics of Teflon tape:
- Non-stick surface allows the tape to be wrapped smoothly around threads
- Stable at high and low temperatures
- Chemically inert – resistant to nearly all industrial chemicals and solvents
- Minimal compressibility allows it to fill gaps between threads
- Tape stretches and conforms as threads are joined
These unique properties make Teflon tape the ideal product for sealing the threads on pipes, fittings, valves and other connections. It fills in the microscopic valleys and grooves between the threads, preventing leaks.
Uses of Teflon Tape
Here are some of the main uses of Teflon tape:
- Sealing pipe threads – Used on threaded pipes, nipples and fittings in plumbing, HVAC and gas systems. Prevents leaks from threaded joints.
- Sealing hydraulic fittings – Used on threaded hydraulic fittings found in hydraulic machinery and equipment.
- Lubricating threads – Reduces friction between threads, making them easier to tighten and unscrew later.
- Sealing hoses and nozzles – Used on hose barb fittings and threaded nozzles to prevent leaks.
- Spark plug threads – Used to lubricate and seal spark plug threads for easier installation and removal.
- Electrical connections – Used to seal threads on some electrical connections like conduit fittings and chases nipples.
Teflon tape is safe to use on metal, plastic and fiberglass threads. It should not be used on oxygen lines or in chlorine or other harsh chemical services that may degrade the tape.
Differences Between White and Yellow Teflon Tape
Now that we’ve covered the basics of Teflon tape, let’s compare white and yellow Teflon tape and see if there are any actual differences between the two colors.
Chemical Composition
The main component of both white and yellow Teflon tape is PTFE resin. This gives the tape its non-stick, lubricating properties. Both tapes contain similar PTFE resin and there is no chemical difference between white and yellow Teflon tape.
Temperature Resistance
PTFE maintains its properties across a wide temperature range from -450°F to 500°F (-268°C to 260°C). It resists cracking at cold temperatures and melting at high temperatures. Both white and yellow Teflon tape have equal temperature resistance.
Sealing Ability
The non-stick PTFE surface allows both colors of Teflon tape to slide smoothly across the threads and conform to the shape of the threads. The tapes have equal compression and gap filling abilities to seal threaded joints.
Strength
White and yellow Teflon tapes typically have similar tensile strengths in the range of 2800-3500 PSI. The color does not affect the mechanical strength of the tape.
Thickness
Standard Teflon tape has a thickness of 0.003-0.005 inches. Both white and yellow Teflon tapes are available in standard and multi-layer thicker versions. There is no difference in available thicknesses between the colors.
Approvals
Teflon tape meets a number of approvals for use in contact with drinking water and in pipe threads carrying fuel gases, liquefied petroleum gas, natural gas and refrigerants. Both white and yellow tapes comply with approvals like NSF/ANSI 61 and UL 969A standards.
Cost
White and yellow Teflon tapes are similarly priced at hardware stores and supply shops. Price varies more based on thickness rather than color. So there is no real price advantage to picking one color over the other.
| Property | White Teflon Tape | Yellow Teflon Tape |
|---|---|---|
| Chemical Composition | PTFE Resin | PTFE Resin |
| Temperature Resistance | -450°F to 500°F | -450°F to 500°F |
| Sealing Ability | Excellent | Excellent |
| Strength | 2800-3500 PSI | 2800-3500 PSI |
| Thickness | 0.003-0.005 in | 0.003-0.005 in |
| Approvals | NSF/ANSI, UL | NSF/ANSI, UL |
| Cost | Low | Low |
When to Use White vs. Yellow Teflon Tape
Since there is no actual difference in properties between white and yellow Teflon tape, both can be used interchangeably in most applications. However, some reasons you may choose one color over the other include:
- Visibility – Yellow Teflon tape is easier to see on threads, letting you confirm full coverage. This helps for pipes and fittings in dim areas.
- Aesthetics – White Teflon tape may be preferred for visible threads to blend in better. For example, on chrome plated fittings and hardware.
- Specific sealant requirements – Some manufacturers or codes may specify white or yellow Teflon tape for certain applications.
- Personal preference – Some plumbers and technicians simply prefer the look or handling of one color over the other.
Additionally, yellow Teflon tape is sometimes used:
- As a visual identifier on gas service lines
- To differentiate between hot and cold water pipes
- To color code different systems or media types
But these are just conventions, not requirements, and either color Teflon tape can technically be used on any threaded application as long as the tape is compatible with the specific material and media.
Proper Application of Teflon Tape
To get an effective seal with Teflon tape, it’s important to apply it properly. Here are some tips:
- Make sure threads are clean – Remove any old tape, residue or burrs
- Wrap tape clockwise as you face the open end of the fitting
- Pull tape tight as you wrap it to keep even tension
- Overlap wraps by 1/2 the tape width for full coverage
- Wrap tape 2-3 times for standard fittings to cover threads
- Cut off excess tape and press end firmly into threads
- Leave first thread uncovered to avoid tape shifting as fitting is assembled
And remember, while Teflon tape helps fill gaps, you still need to properly tighten threaded joints to finish sealing them. Teflon tape compresses 50-80% when tightened, so don’t overdo it on the number of wraps which can cause too much bulk.
Conclusion
In summary, white and yellow Teflon tape are essentially identical products in terms of their chemical, mechanical and sealing properties. The main difference is visibility – yellow Teflon tape is easier to see on threads during application. Both tapes can be used interchangeably in most situations with no difference in performance.
The key is using high quality tape and applying it properly to get a leak-free seal. Following the product specifications and application tips outlined in this article will help you successfully use Teflon tape on threaded connections in plumbing, gas, hydraulic, electrical and other systems.