What is Class 1? Class 1 represents a material which shall have a flame spread rating of not over 25 without evidence of continued progressive combustion and a smoke-developed rating of not over 50.

What does class 1 duct mean?

To be identified as an official Class 1 duct, the duct and connector materials must have a flame spread rating of no greater than 25 with no evidence of continued progressive combustion, and a smoke developed rating of no more than 50.

What are the 4 types of duct systems?

Namely, flexible ductwork, rigid ductwork, and semi-rigid ductwork. We’ve compiled information on each of these duct systems. These ducts are typically tube-shaped and made of a wire coil covered with a bendable, durable plastic, and surrounded by insulation.

What is class one duct tape used for?

UL 181B-FX Listed film tape for use on Class 1 Flex Duct for connecting, joining, sealing and patching flexible air ductwork. DC 181 features an acrylic adhesive system, high performance in temperatures ranging from -10 F to 210 F, and is clearly printed with the UL Listing to ensure every job is code compliant.

What is a Class 0 duct?

Class 0 has a rating of zero (0) flame spread and smoke-developed index. … Class 0 indicates flame spread and smoke-developed indexes of zero; Class 1 indicates a flame spread index not greater than 25 and a smoke-developed index of not greater than 50, when tested to ASTM E 84.

What is class 0 flexible duct?

In order to achieve “Class 0”, the duct must have a Flame Spread Value equal to 0 and a Smoke Developed Index equal to 0 when tested to the Surface Burning Characteristics test (UL723, ASTM E-84).

What UL 181?

UL 181 is a requirement applying to materials in the fabrication of air duct and air connector systems. The differences between an air duct and air connector lie in the testing they undergo by UL and as a result, the allowed uses by code.

What is FlexFix tape used for?

Description. FlexFix™ UL181B-FX Film Tape is a tough, contractor grade closure system for Class 1 flexible air ducts and connectors, sealing reflective and bubble insulation and suitable for metal to metal connections in HVAC and refrigeration applications.

Is Nashua duct tape flammable?

Additional Product Information. The tape measures 1.89 inches by 9.8 yards. Its adhesion to steel is 90 ounces per inch, and its tensile strength is 11 pounds per inch. It is UL 723 classified and meets flammability requirements for use on Class 1 ducts.

What is shurtape DC 181 used for?

DC 181 is designed to prevent air loss when connecting, joining, sealing and patching flexible air ductwork: Excellent conformability to uneven surfaces. Easy to unwind. Hand-tearable.

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What kind of duct is best?

Though there are different types of ductwork available in the market today, Sheet metal is most recommended as this type of air duct is non-porous in nature and thus does not allow mold or bacteria to breed in the air ducts. Sheet metal ductwork also helps you prevent potential health risks of fiberglass air ducts.

What kind of ductwork is needed for central air?

Galvanized steel and aluminum are the most common materials for sheet metal ducts. Aluminum in particular is relatively light and easy to install. They are also the least likely to harbor dangerous molds or growths because they have non-porous surfaces.

Which ducting is the best?

Semi-rigid ducting is viewed as the best type of ventilation ducting available and offers installers and those using semi-rigid ducting in their ventilation system a number of benefits.

What is UL listed tape?

UL Listed foil tapes are used to seal air duct and air connectors and have been stringently tested for flame resistance, mold growth and humidity, static load, impact, pressure, collapse, tension and more.

Which type of duct undergoes more rigorous testing?

Which type of duct undergoes more rigorous testing before it is labeled? Flexible duct.

What is a plenum and where would I find one?

In building construction Plenum is a separate space provided for air circulation for heating, ventilation, and air-conditioning. It is commonly found in the space between the structural ceiling and a drop-down ceiling or under a raised floor.

What does UL mean in HVAC?

When it comes to making a purchase, finding a reliable product is sometimes difficult to recognize. Luckily, UL (Underwriters Laboratories) approved products make that decision simpler, ensuring required standards are met such as safety, sustainability, performance, and quality.

How long does flexible ductwork last?

What is the functional lifespan of a flexible duct system? A search of industry articles, blogs, and chat rooms indicates it lasts from 10 to 25 years. Most flexible duct manufacturers warranty their products for about 10 years.

Does Flex duct meet code?

An International Association of Plumbing and Mechanical Officials committee has approved a change to the group’s Uniform Mechanical Code, limiting the use of flexible ductwork to 5 feet or shorter runs. … Flex duct goes easily into areas where metal ductwork is difficult to install, its makers say.

What is a flexible air connector?

FLEXIBLE AIR CONNECTOR. A conduit for transferring air between an air duct or plenum and an air terminal unit or between an air duct or plenum and an air inlet or air outlet. Such conduit is limited in its use, length and location. 603.6.1 Flexible air ducts.

What kind of tape do you use for dryer vents?

Tape for Dryer Vents Any time you’re sealing the connections between heating, cooling or dryer ducts and vents, you need a heat-resistant tape, like aluminum foil tape, which is made for this purpose. Foil tape doesn’t dry out, so once the dryer duct and vent are installed, the system will remain secure.

Is all foil tape heat resistant?

Extreme cold and heat temperature versatility. Our foil tape works in temperatures ranging from 248°F to -22°F and can be applied in temperatures ranging from 14°F to 104°F. Most tapes do not perform well in cold temperatures. … Conversely, excessive heat can melt the adhesive on some tapes, rendering it useless.

What tape is heat resistant?

Fiberglass tapes, basalt tapes, and aluminum foil tapes are commonly used in high temperature gasketing, sealing, lagging, thermal insulation, and encapsulation applications around furnaces, ovens, and hot pipes.

Is Flex Seal tape UV resistant?

Powerful adhesive with a thick, flexible rubberized backing that conforms to virtually any shape and surface, even underwater. Gets stronger with time and pressure. UV resistant, VOC- free, withstands extreme temperature and weather conditions.

Is duct tape waterproof?

Duct tape is water resistant, not waterproof. It will work in a pinch until a more permanent solution can be applied, but over time the adhesion will peel away when completely submerged in water.

Is Flexfix tape heat resistant?

All temperature performance. Film backing is tough yet hand tearable for ease of use. Meets UL181B-FX requirements.

Who makes shurtape?

Shurtape is owned by the Shuford family. The Shufords have been involved in business in Hickory since 1880, when Abel Alexander Shuford built the first yarn factory in what would become Shuford Mills.

Is round or square duct better?

Round air ducts are best suited for high-pressure HVAC systems. Their design creates less friction, allowing air to flow easier throughout the building. Rectangular ducts aren’t as efficient with their airflow, which means they can create more harm than good in a high-pressure system.

Why flex duct is bad?

Flexible ductwork not only resists airflow, but is also more susceptible to a poor installation. Any number of factors can go wrong, including a poorly sealed joint, excessive length that lacks support and crumpled sections. Also, the material itself is less durable than sheet metal.

Is fiberglass ductwork bad?

When ducts are damaged or deteriorating, they can introduced particles of fiberglass into the air you breath. According to the American Lung Association– Inhaling fiberglass can reduce lung function and cause skin eye and throat irritation, in humans and animals.

What is the most durable material in ductwork?

Made of galvanized steel or aluminum, rigid sheet metal is the most common type of ductwork. The thick, solid wall makes the duct very durable.