Does Flex duct reduce airflow?

If you’ve ever seen kinked or sagging flex duct and wondered whether that was a problem, you were onto something! Since flex duct, by definition, is flexible, it often flexes in ways we don’t want it to. The result is poor airflow and ineffective HVAC systems.

What is the main problem with flex duct?

Too often, flex ducts are not installed properly, and they end up kinked, bunched up, undersized, or sagging. These issues can cause increased resistance in the duct system, resulting in too little airflow reaching a building’s heating and cooling equipment.

What is the best location for HVAC ducts?

Air Ducts Near the Ceiling Are Most Effective
One of the most important things to be aware of when deciding on vent placement in your new home is that typically, air ducts placed near or within the ceiling are the most effective option in terms of energy efficiency.

Is rigid or flexible duct better?

Flex ducts are better for existing trunk-and-branch heating and cooling systems. This is because they’re more versatile and flexible. Metal ducts are more rigid due to the nature of steel, making them ideal to build an entire HVAC system.

What is the disadvantage of flex duct?

The downside of flex ducting is that it is considered temporary with an acknowledged lifespan of only about 15 years. Another major disadvantage is that they are a little too flexible, so they are often incorrectly installed. And with greater friction than metal ducts, proper sizing is critical.

How long will flex duct last?

10 to 25 years

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.

Is Flexible ducting any good?

Flexible ductwork is made of a thin, pliable material. Not only does this make it less durable than metal, but it also means that flexible ducts are more likely to become damaged in the short term. It’s difficult to install the material without damaging it, as rips and tears can happen very easily.

Does Flex duct sweat?

Flex ducts themselves do not sweat, however if the connection points are not sealed correctly and duct leakage is occurring then you can get sweating at those points. The good news is with a flex duct system we can either hand seal the connection points or perform an Aeroseal to stop the water.

How often should flex duct be supported?

every once 4 feet

Supports should be installed at least every once 4 feet. The maximum allowable sag in flexible duct is one-half inch per foot. (Source: Calcs Plus.) Place supports at each connection between flex duct and rigid metal duct.

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 type of ductwork 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.

How do I know what size flex duct I need?

One simply needs a ruler or measuring tape along with the end of the hose or outlet. Keep in mind that you have to begin the measurements from the interior wall of the circle. The distance to the opposing point of the circle is the measure of the flex duct sizing for the inner diameter.

Is flex duct waterproof?

FlexClad™ is the flexible, weatherproof, economical, and easy-to-install jacketing system for pipe and duct applications. Since 1961, MFM Building Products has been a manufacturer of innovative, waterproofing membranes for the HVAC/Insulation and construction industries.

Can you use flex duct basement?

Flex ducts are very easy to bend around roof rafter components in the attic, floor joists in the basement, as well as other difficult areas in the framing of a house.

How long has flex duct been around?

150 years

Reply: history of flexible air ducts reflected in U.S. patents. Certainly flexible ducting has been around for more than 150 years and may have originated with flexible elbows for metal flue vent connector.

How often should flex ductwork be replaced?

If your ductwork is over 15 years old, you probably should replace it. Ductwork has a maximum lifespan of 20-25 years. By 15 years, however, it begins to deteriorate, significantly reducing your HVAC system’s efficiency, so replacement is the prudent option.”

How do you clean a flexible duct?

The two most popular ways to clean a duct system are with a vacuum or a brush. The vacuum method involves blowing air into one end of the ducts and sucking air from the other. The brush cleaning method involves inserting a brush into the duct and attempting to collect or loosen the dust.

Can I replace metal duct with flexible?

Metal duct can still be found in many older homes, but flexible duct is more prevalent in newer homes. Both work well. Still, should you decide to change from metal to flexible duct, don’t waste money on an HVAC contractor. It’s a time-consuming job, but definitely one you can do yourself.

Is round or square duct better?

With less surface area, no corners, and better airflow, round metal duct work eliminates the chances of dirt and bacteria accumulating in the duct.

Is fiberglass ductwork safe?

Fiberglass, at a minimum, is an acute physical irritant to the skin, eyes, and upper respiratory tract. While no long-term health effects should occur from touching fiberglass.