Which is better flex duct or metal?

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.

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.

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.

How long can you run flex duct?

5 feet

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 manufacturers oppose the limitation.

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.

Should you replace old ductwork?

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 much friction do you lose in flex duct?

Air friction loss of 90° bends depends on the bend radius, and it is shown graphically as equivalent length of straight duct in terms of duct diameters versus the ratio of centerline bend radius to duct diameter. Flexible Duct – Straight Run Friction Loss per 100 ft.

How do I increase the airflow in my HVAC system?

5 Ways to Improve AC Airflow for Better Efficiency

  1. Unblock AC Vents. Your AC system flows in a circular pattern. …
  2. Clean AC Vents. AC vents tend to accumulate dust and debris floating in your house. …
  3. Check Your Filters. …
  4. Find and Fix Leaks. …
  5. Schedule Regular HVAC Maintenance.


How do you increase airflow in ducts?

Increasing airflow in ductwork can be done by cleaning the air filters and ductwork. By adding inline duct booster fans and/or air dampers significantly can improve airflow in weak areas.

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.

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.

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.

How much does it cost to re wrap ductwork?



of ductwork insulation is typically $1,000–$2,700. Costs vary depending on the insulation material you choose. HVAC duct insulation costs $1.15–$5.50 per sq.
Highlights.

National Average Cost Minimum Cost Maximum Cost
$2,500 $750 $6,000

Why is there no flex duct?

Quote from the video:
Quote from Youtube video: Похожие запросы

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 metal ductwork insulated?



Metal ducts for residential HVAC systems are typically insulated on the exterior using a “duct wrap,” such as fiberglass blanket insulation with a foil-faced vapor barrier. Duct wrap comes in four-foot-wide rolls 50 to 100 feet long and in R-values that range from R-4 through R-8.

When should you choose to use sheet metal duct work?

The main reason to choose sheet metal ductwork is that it is proven to be effective. If you have a new home or an existing home that needs a good set of ducts, sheet metal ductwork is long-lasting and durable. When installed correctly and properly maintained, you may not need any repairs for a long period of time.

How often should you replace your ductwork?

about 10-15 years

Ducts are designed to last for about 10-15 years on average. They are made from a combination of materials such as fiberglass and plastic. At some point, these ducts will get damaged. The sooner you see signs of damage and do something about it, the better.

Can old ductwork make you sick?

Develop Respiratory Infections, Disease
If your family is getting sick more than normal, experiencing coughing, sneezing, sore throats, runny noses, nasal congestion, headaches, and low-grade fevers, they may have upper respiratory infections as a result of dirty air ducts.

Does cleaning air ducts really make a difference?

Duct cleaning has never been shown to actually prevent health problems. Neither do studies conclusively demonstrate that particle (e.g., dust) levels in homes increase because of dirty air ducts or go down after cleaning.

Is replacing ductwork messy?

The Mess Is Minimal
Unless your home has a flat roof (which means the ducts are very difficult to access), we can usually install new ducts without ripping out walls or ceilings.

Should fiberglass ducts be replaced?

The problem with old fiberboard duct is that the fiberglass particles come loose and circulate through the house. These particles are inhaled by people in the home (or office), which is hazardous to everyone’s health. When this occurs, the ductwork should either be replaced or reinsulated with safer material.

Why is my house so dusty?

Both low humidity and high humidity play a role in why your house is so dusty. When the air is dry, your air can be extra dusty. But when it’s too high, it can feed mites and promote mold growth. If your air is dry, run a humidifier so that you can reach a comfortable level.