What is duct design?

Asked By: Jeferson Kalai | Last Updated: 16th January, 2020
Category: home and garden indoor environmental quality
4.3/5 (231 Views . 13 Votes)
Ducts are conduits or passages used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air. A duct system is also called ductwork. Planning (laying out), sizing, optimizing, detailing, and finding the pressure losses through a duct system is called duct design.

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Herein, what is duct system?

THE DUCT SYSTEM, used in air heating and air cooling your home, is a collection of tubes that distributes the heated or cooled air to the various rooms. This system can make a big difference in both the cost and the effectiveness of heating and cooling the home.

Furthermore, how do air ducts work? As earlier stated, air ducts are tubes connecting a HVAC system with different air vents installed in a house. They system forces the heated or cooled air through the air ducts and then through the air vents in order to heat or cool the house.

Thereof, what are the types of ducts?

There are three common classifications of ducts - conditioned air ducts, recirculating-air ducts, and fresh-air ducts.

How are ducts made?

Galvanized steel and aluminum are the most common metals used to create ducts. Many metal duct manufacturers add fibreglass liners to insulate the duct and reduce air leaks. A wire coil in the plastic helps the duct retain its desired shape. Plastic ducts sometimes attach to more rigid metal or fibreglass duct systems.

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Can I install my own HVAC system?

Install Your Own HVAC Unit or Use a Pro? In most all DIY cases that have to do with installing a new HVAC system, your free labor cannot compete with their unit prices. Of course the decision is yours, but in this case the amount you can save is minimal when all factors are taken into consideration.

What is HVAC sheet metal?

Fabricated sheet metal is commonly used in the ductwork of HVAC systems. Traditional ductwork is installed in commercial and industrial buildings for the heating and cooling systems. This would eliminate the need for all those extra pipes and fittings that only succeed in using more energy to run the HVAC system.

How do you build a return air duct?

How to Install a Return Air Duct
  1. Locate where you want your return air ducts.
  2. Go into the basement and locate the holes.
  3. Install the square return air duct perpendicular to the joists.
  4. Cut a hole in the bottom of the return duct next to where the furnace is.
  5. Install your HVAC filter into your filter rack.

What is the function of duct?

Ducts are conduits or passages used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air. The needed airflows include, for example, supply air, return air, and exhaust air.

What size duct should I use?


10 inches per 100 feet of lineal duct. This "Equal-Friction" method of duct sizing should be adequate for normal residential furnace heating and air conditioning applications. Larger volumes or higher static pressures should be dealt with on an individual job basis.

How do I know if my air ducts need to be cleaned?

5 Signs You Should Have Your Ducts Cleaned
  1. You Haven't Changed the Air Filter in Months.
  2. The Registers and Vent Covers Have Visible Dust.
  3. You Detect Mold in or Around Your HVAC System.
  4. Airflow Isn't Consistent From Room to Room.
  5. You Can Hear Noises in the Ductwork.

What is the best material for ductwork?

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.

What is the difference between air duct and vent?

Return vents are also covers for the openings in your walls but the difference is that they are connected to your return ducts. The AC vent sucks the air from the rooms into the return vents through the ductwork and back to your heating and cooling system.

Can you use flex duct return air?

Re: Flex Duct on Return Air Diffusers - Yes or No? Flex duct effectively creates a tight radius elbow where it turns into the top of a diffuser. The high pressure loss is further increased because the flex fabric gathers at the inside of the throat and reduces the effective diameter.

Where are air ducts located?


Ducts should always be located within the conditioned envelope of the building, ideally within the framing of floors, ceilings and walls, and they should be maintained so air does not leak out of or into them.

Does Flex duct reduce airflow?

Friction is the enemy of airflow. Unlike rigid ducts, which are cut to length within a tolerance of 1 inch or less, it's easy to cut a length of flexible duct that's several feet longer than is needed to get from point A to point B [2A]. That creates slack in the duct, which reduces airflow for two reasons.

Can you use heating ducts for air conditioning?

Are all heating ducts suited for an add-on cooling system? Most heating systems are compatible with add-on air conditioning, but not all. In some cases there might need to be some changes made to the layout of the existing system to make it compatible.

What is the return air duct?

The ductwork in your residential forced-air HVAC system is the network of pipes through which heated or cooled air travels. Return air ducts balance airflow in your HVAC system — The primary role of return ducts is to bring air that has been warmed or cooled back to your furnace or air conditioner.

Why is it called duct tape?

Duct Tape was Originally Named “Duck” Tape and Came in Green, Not Silver. Duct tape was originally invented by Johnson & Johnson's Permacel division during WWII for the military. The military specifically needed a waterproof tape that could be used to keep moisture out of ammunition cases.

What is meant by HVAC?


Short for heating, ventilation, and air conditioning. The system is used to provide heating and cooling services to buildings. HVAC systems have become the required industry standard for construction of new buildings.

Why the ducts are used in an air conditioning system?

Ductwork channels conditioned air to vents, takes return air back into the system and transports exhaust air and waste heat to the exterior of your home. Ducts serve a triple purpose: They carry warmth in winter, hold cool air in summer and provide ventilation for better indoor air quality throughout the year.

What is ductless gland?

1. ductless gland - any of the glands of the endocrine system that secrete hormones directly into the bloodstream.