What is Ductwork? – An Overview
Ductwork is used in heating, ventilation, and air conditioning (HVAC) to provide and extract air, fumes and toxins. These airflows include, supply air, return air, and exhaust air. Ductwork is one method of ensuring acceptable indoor air quality as well as heating or cooling requirements.
Main Ductwork materials
The main ducting materials used to construct rectangular, round, or oval cross-sectional shapes are:
Galvanised steel can easily be cut and bent to form ductwork so is the most commonly used material. It can be wrapped or lined with thermal insulation, both to reduce heat loss or gain through the duct walls and water vapour from condensing on the exterior of the duct when the duct is carrying cooled air. Insulation, particularly duct liner, also reduces duct-borne noise. Both types of insulation reduce ‘breakout’ noise through the ducts’ sidewalls.
Mild steel is an alternative to galvanised steel as it can be formed before the galvanising process, being in it’s raw form, it is suitable for welding.
Stainless steel is a higher specification to mild steel as it much high anti-corrosion properties so is suitable for food, chemical and nuclear applications. It can be welded and formed and can be used for larger sized ductwork.
Plastic ducting is becoming more popular, it is lightweight and often aesthetically pleasing and is often used in modern applications.
Polyurethane duct board
More rectangular ductwork is being manufactured from “duct board”, thanks to the fact that custom or special shapes and sizes of ducts can easily be shop or field fabricated. The ductwork construction starts with the plotting of the single pieces on the panel. The pieces are then, bent and closed through an operation of gluing, pressing and taping. Having obtained the various ductwork sections, they can easily be installed by using an invisible aluminium flange system.
Fibreglass duct board
Fibreglass panels provide built-in thermal insulation and the interior surface absorbs sound, helping to provide quiet operation of the HVAC system.
Flexible ducts, known as flex, have a variety of configurations, but for HVAC applications, they are typically flexible plastic over a metal wire coil to make round, flexible duct. Flexible duct is very convenient for attaching supply air outlets to the rigid ductwork but pressure loss is higher than for most other types of ducts.
Ductwork system components
Complete ducting systems contain many other components:
- Air Handling/Heat Recovery Units
- Heaters, Coolers
- Vibration isolators
- Terminal units
- Air terminals
- Stacks, boots, and heads
Fleetwood Sheet Metal can offer a full production cycle from design (by external design engineers) to manufacture, installation and testing. We enjoy an excellent reputation across the North West UK working for many high profile clients.
We operate out of purpose built factory with our professional experienced workforce. Our projects cover many sectors from chemical plant work to standard office ventilation, local government buildings, leisure and public buildings. We can offer standard galvanised ventilation systems, fire rated, stainless steel bespoke systems, plastic, etc this includes the supply and installation of all plant, grilles, diffusers and other ancillary equipment.
This is backed up by our experienced team of project management engineers, CAD/CNC designers, manufacturing and installation specialists to ensure the project is completed to our exacting standards within your timescale.
Fleetwood Sheet Metal can provide the full system and advise on the best application for your environment, please contact us for more details.