Air Conditioning Ducts 101: A Comprehensive Guide

Air conditioning ducts are a crucial part of your home's cooling system, responsible for distributing cooled air throughout your space.

A standard air conditioning duct typically ranges in size from 6 to 20 inches in diameter, with the most common size being 14 inches.

Proper duct installation is key to efficient cooling and can save you up to 30% on your energy bills.

A well-designed duct system should have a smooth, continuous path from the air handler to the supply registers, with minimal bends and turns to reduce pressure drops.

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You've got options when it comes to choosing the right type of air conditioning duct. Commonly used types of ductwork include round metal ducts, rectangular metal ducts, insulated flexible ducts, and spiral metal ducts.

The size of your HVAC system will determine which type of ductwork you need. Depending on the size of your system, you may need one type or many kinds of ductwork.

Rigid ductwork is a popular choice due to its hard, reliable, safe, and enduring nature. Rigid ductwork comes in a variety of shapes, sizes, and materials.

Central air conditioning systems use a series of ducts to re-distribute cooled air throughout your home.

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Bad air conditioning ducts can be a real nuisance, causing a range of problems from noisy ducts to sinus issues. At least 20% of the air traveling through the ducts escapes through leaks, holes, and bad connections.

If you notice that your home is dusty, or you're constantly sweeping and dusting, it may be a sign that your air ducts need cleaning. Dust and pollen can seep into your ductwork through holes or loose connections and infiltrate your home.

Some common signs of bad air conditioning ducts include high utility bills, spaces or rooms that are difficult to heat or cool, and ducts located in areas prone to leaks, such as attics or crawl spaces.

Here are some common signs of bad air conditioning ducts:

If you're experiencing any of these issues, it may be time to have your air ducts inspected and cleaned.

Dust collection in your house could put an old library to shame. If you have a lot of dust, it's likely seeping into your ductwork through holes or loose connections.

Everyone in your household is sneezing, especially those with allergies like little Timmy. This is a clear sign that dust or pollen is infiltrating your home through your air ducts.

A typical HVAC system only delivers 57% of its rated capacity due to air duct problems.

At least 20% of the air traveling through your air ducts escapes through leaks, holes, and bad connections. This means that a significant amount of your heating and cooling energy is being wasted.

Utility bills in winter and summer months above average relative to rate fluctuation are a common sign of leaky or poorly performing air ducts. This is because the escaped air is essentially money down the drain.

Spaces or rooms that are difficult to heat or cool are another sign that your air ducts may be leaking. You might notice that some areas of your home are always colder or warmer than others.

Duct location in an attic, attached garage, leaky floor cavity, crawl space or unheated basement can also contribute to leaks. These areas are prone to moisture and temperature fluctuations, which can cause your ducts to deteriorate over time.

Here are some common signs of leaky air ducts:

There are four common air duct designs, including the plenum or radial duct system, reducing extended plenum system, extended plenum system, and perimeter loop system. Each has its own set of challenges.

HVAC contractors must calculate airflow and determine the right ducts to meet a home's requirements, but flaws are all too common in HVAC air duct design. Good sheet metal workmanship is a thing of the past, with inferior installations becoming the norm since the 1970s.

Flaws in air duct design and installation can lead to reduced efficiency, increased energy bills, and even system failure.

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Hot and cold spots in your home are a clear indication of air duct issues. If you notice a temperature difference of more than 3 degrees between rooms or areas, it's a sign that your air ducts need attention.

You might have felt this before, walking into a room that's too hot or down the stairs where it's noticeably colder. A thermometer can confirm the discrepancy.

A professional HVAC technician can pinpoint the cause of the problem and come up with a plan to fix it. They'll put that plan into action, so you can enjoy a comfortable temperature throughout your home.

High utility bills can be a frustrating and costly problem. Up to 30 percent of the air in your ducts may be escaping.

This means that conditioned air is leaking out, causing your blower fan to work harder and ultimately leading to higher electricity bills. You might not even notice it's happening.

A utility usage report can reveal the issue, showing that you're using more electricity than similar homes in your neighborhood.

Flexible ducts are often found in tricky spaces where more rigid ductwork won't fit. However, many HVAC contractors take the easy way out and leave the flexible ducts twisted, tangled, and kinked.

This practice reduces airflow, which can cost you big money. The metal rib cage in flex ducts is designed to provide support, but when twisted or tangled, it can cause even more airflow restriction.

Flexible ducts are meant to be stretched and cut to fit into place fully extended, but many contractors don't take the time to do this. Instead, they leave the ducts in a state that's far from ideal.

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Minor duct repairs are easy to make, but qualified professionals should seal and insulate ducts in unconditioned spaces to ensure the use of appropriate sealing materials.

To maintain your air distribution system, ensure that furniture and other objects are not blocking the airflow through your registers, and vacuum the registers to remove any dust buildup. This simple task can make a big difference in the efficiency of your air conditioning system.

Before hiring a professional to install new ducts, check for air leaks and seal them using mastic or heat-approved tapes. Remember that insulating ducts in the basement will make the basement colder, so consider insulating both the ducts and the basement walls.

Here are some common issues that can affect your air conditioning ducts:

If you notice any of these issues, consider upgrading your return-air grilles, undercutting doors for return air, or installing a jumper duct to improve the airflow in your home.

Long runs can be a problem with air conditioning ducts. A bigger duct size is often the solution to ensure enough air reaches the room at the end of the supply duct.

Not enough air reaching the room at the end of the supply duct is a common issue.

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Cleaning your air ducts is an essential part of maintaining your air conditioning system. The U.S. Environmental Protection Agency (EPA) recommends cleaning your air ducts only if you have allergies or unexplained symptoms.

However, a study published in Environmental Monitoring and Assessment found that HVAC duct cleaning can effectively decrease certain airborne pollutants, even if contamination isn't visibly obvious or immediately symptomatic. The study observed that cleaning processes temporarily increase airborne particles and bioaerosols during the procedure due to disturbance.

A professional duct cleaner can remove a wide range of debris and contaminants from your air ducts, including dust, cobwebs, debris, pet hair, rodent hair and droppings, paper clips, calcium deposits, children's toys, and more. Ideally, the interior surface will be shiny and bright after cleaning.

Insulated fiber glass duct liner and duct board can be cleaned with special non-metallic bristles, while fabric ducting can be washed or vacuumed using typical household appliances.

Sealing is a crucial step in maintaining and repairing air conditioning ducts. You should never use cloth-backed, rubber adhesive duct tape to seal your ducts - it tends to fail quickly.

It's better to use mastic, butyl tape, foil tape, or other heat-approved tapes that have the Underwriters Laboratories (UL) logo. These tapes are more durable and long-lasting.

Be aware that insulating ducts in the basement will make the basement colder, so consider insulating both the ducts and the basement walls. However, if the heat ducts are fully insulated, water pipes and drains in unconditioned spaces could freeze and burst.

To prevent this, you can use an electric heating tape wrap on the pipes. Check with a professional contractor for the best solution.

Here are some common types of duct sealants:

Automated duct sealing is often used in commercial construction and multi-unit residential construction, but it can be impractical for the average homeowner due to the high cost.

Proper duct maintenance is crucial to ensure your air conditioning system runs efficiently. Sealing your ducts to prevent leaks is especially important if they're located in an unconditioned area like an attic or vented crawlspace.

Sealing your ducts can prevent heated or cooled air from escaping and unconditioned air from entering, which can be forced into return ducts through unsealed joints. Qualified professionals should seal and insulate ducts in unconditioned spaces to ensure the use of appropriate sealing materials.

Keep your air distribution system running smoothly by ensuring furniture and other objects aren't blocking airflow through your registers. Vacuuming your registers regularly can also help remove dust buildup.

Existing duct systems often suffer from design deficiencies in the return air system. Simple upgrades, such as installing new return-air grilles or undercutting doors for return air, can help improve airflow in rooms with insufficient return air.

Increasing the size of the supply duct or adding an additional duct can provide the needed airflow to rooms with inadequate supply ducts or grilles.

Waterproofing is crucial for external ductwork exposed to the weather. This can be achieved with a sheet steel coated with aluminium or an aluminium/zinc alloy.

Proper waterproofing helps prevent damage from moisture and ensures the longevity of your air conditioning ducts. It's essential to choose a reliable coating that can withstand the elements.

A multilayer laminate or a fibre reinforced polymer can also be used for waterproofing external ductwork. These materials offer excellent durability and protection against water damage.

Regular inspections and maintenance can help identify potential waterproofing issues before they become major problems. Don't wait until it's too late – address any signs of moisture or damage promptly.

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Air conditioning ducts are made up of more than just the ducts themselves. Complete ducting systems contain many other components.

Registers are one of the key components, providing a way to direct airflow into a room.

Takeaways from a well-designed duct system include improved airflow and reduced energy consumption.

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Flexible air ducts are made of a metal wire coil wrapped with a layer of flexible plastic, and they have thermal insulation made of glass wool or other materials.

They typically look like a cube and have no elbows or offsets, making them a great option for homes with limited space.

Flexible ductwork is inexpensive, lightweight, and easy to install, making it a popular choice for many homeowners.

However, it's essential to note that flexible ducts can be prone to twists, tangles, and kinks if not installed correctly, which can reduce airflow and increase energy costs.

In fact, many HVAC contractors are too lazy to stretch flex ducts and cut them to fit, leaving them twisted and tangled, which can be a costly mistake.

To use flexible ducting effectively, it's crucial to pull the duct tight so you get the full internal diameter, reducing resistance and improving airflow and ventilation efficiency.

Minimizing bends and kinks is also essential, as they can affect airflow and ventilation efficiency.

There are various types of flexible ducting available, including polyurethane, aluminium and aluminium insulated, acoustic, and rectangular flexible ducting, as well as semi- and combi-flex.

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Galvanized steel is the standard material used in fabricating ductwork, thanks to its zinc coating that prevents rusting and avoids the cost of painting. It's the most common material used, and for good reason.

Galvanized steel ductwork is typically lined with faced fiberglass blankets, known as a duct liner, or wrapped externally with fiberglass blankets, known as a duct wrap. This helps with insulation purposes.

A double-walled duct is also used when necessary, which has an inner perforated liner, a layer of fiberglass insulation, and an outer solid pipe. This setup provides extra protection and insulation.

Rectangular ductwork is commonly fabricated to suit by specialized metal shops. It usually comes in 4 ft sections for ease of handling.

Round duct, on the other hand, is made using a continuous spiral forming machine, which can create ducts in nearly any diameter and to any length.

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Fiberglass Lined ducts are a type of rigid duct that can be lined with fiberglass for added sound dampening capabilities.

They're often preferred in commercial buildings and offices because they can effectively reduce the noise of the air conditioner.

However, fiberglass lined ducts are not without their drawbacks. They can deteriorate over time.

This can lead to the release of small particles of fiberglass into the air, posing serious health issues like asthma.

Fiberglass is also porous, making it a breeding ground for mold and bacteria.

Cleaning fiberglass-lined air ducts can be a challenge due to their porous nature.

A complete air conditioning duct system is made up of many components besides the ducts themselves. These include filters, heating and cooling units, and other essential parts that work together to keep your home comfortable.

Filters are a crucial component, as they clean the air before it's circulated throughout your home. This is mentioned in Example 3, where it's explained that cleaned air is sent back to the areas of your house.

Ducts are the main pipes that transport air throughout your home, and they're often used in conjunction with central air conditioning systems. In Example 2, it's mentioned that central air conditioning systems use a series of ducts to re-distribute cooled air throughout your home.

The ducts themselves are also an important component, as they can affect the efficiency and effectiveness of your air conditioning system.

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Vibration isolators are a crucial component in air conditioning ducts, helping to reduce noise and vibration from blowers in air handlers.

They are inserted into the duct immediately before and after the air handler to prevent vibration from being transmitted to the attached ducts.

The rubberized canvas-like material of these sections allows the air handler to vibrate without transferring much vibration to the ducts.

This flexible section can also reduce noise that occurs when the blower engages and positive air pressure is introduced to the ductwork.

By using vibration isolators, you can minimize the disturbance caused by air conditioning systems and create a more comfortable environment for building inhabitants.

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Smoke and fire dampers are crucial components of air conditioning ducts, particularly in areas where ducts pass through firewalls or fire curtains.

They are installed in ductwork to prevent the spread of smoke and fire. Smoke dampers are motor-driven and have a probe that detects smoke in the duct. Once smoke is detected, the actuator closes the smoke damper.

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Fire dampers, on the other hand, are not triggered by electrical systems, making them a reliable option in case of an electrical failure. Vertically mounted fire dampers are gravity-operated, while horizontal fire dampers are spring-powered.

A fire damper's most important feature is a mechanical fusible link that melts or breaks at a specified temperature, causing the damper to close and seal the duct. This effectively contains the fire and blocks the necessary air to burn.

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Fabric ducting is actually an air distribution device, not a conduit for conditioned air, so it's often referred to as a fabric air dispersion system.

Fabric ducts can provide a more even distribution and blending of conditioned air than a conventional duct system, and they're usually made of polyester material.

They're available in various colors, and some can even be customized with silk screening or other forms of decoration.

Fabric ducts can be made of porous or non-porous fabric, and the choice depends on whether the application would require an insulated metal duct.

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Air-permeable fabric is recommended if the application requires an insulated metal duct, as it won't create condensation on its surface.

Porous material can be healthier for occupants, as it repels dust and other airborne contaminants, and it also tends to require less maintenance.

Fabric ducts made from more than 50% recycled material can be certified as green products.

They're not rated for use in ceilings or concealed attic spaces, but there are products available for raised floor applications.

Fabric ducting usually weighs less than conventional ducting, which makes it easier to install and puts less stress on the building's structure.

Fabric ducts require a minimum range of airflow and static pressure to work effectively.

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Installation of air conditioning ducts is a crucial step in ensuring your home stays cool and comfortable. Proper ductwork installation typically occurs when building a new home or replacing old ducts and HVAC vents.

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It's essential to rely on qualified technicians for ductwork replacement or new installation to ensure air ducts and duct vents are properly sized, located, and securely mounted.

Air duct installation issues have become more common since the 1970s, with inferior workmanship and leaks leading to energy loss and inefficient airflow. To avoid this, have a professional inspect and assess your duct system for proper installation or repairs.

In new home construction or retrofits, proper duct system design is critical for energy efficiency. Well-designed duct systems distribute air properly throughout your home without leaking, keeping all rooms at a comfortable temperature.

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Proper air vent location is crucial for your HVAC system to function efficiently. The location of air vents can greatly impact the overall performance of your heating and cooling system.

Air vents installed in out-of-sight areas like closets can prevent supply air from properly heating or cooling the room. This can cause your HVAC system to work harder, leading to increased wear and tear.

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If air vents are blocked by furniture, your HVAC system will have to work even harder to achieve the desired temperature. This can significantly shorten the lifespan of your HVAC system.

The optimal location for air vents is usually in open areas, such as hallways or living rooms. This allows the supply air to circulate freely and heat or cool the room effectively.

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Volume control dampers are a crucial component in air conditioning ducts, allowing for adjustments to the volume of air flow to various parts of the system.

They provide a method of regulation, which is essential for maintaining optimal indoor air quality and comfort levels.

Ducting systems often require these dampers to ensure that air is distributed evenly throughout the space.

Volume control dampers can be manual or automatic, depending on the system's complexity.

Zone dampers offer automatic control in simpler systems, while variable air volume (VAV) systems allow for more sophisticated control.

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Installing air conditioning ducts can be a complex task, but understanding the basics can help you make informed decisions. It's essential to ensure air ducts and duct vents are properly sized, located, and securely mounted.

Air duct installation typically occurs when you're building a new home or replacing old ducts and HVAC vents. This means relying on qualified technicians for ductwork replacement or new installation.

Proper ductwork insulation is crucial to prevent energy loss and inefficient airflow. If your existing system has inadequate ductwork insulation, you may experience higher energy bills.

To ensure a well-designed duct system, consider the following: ducts should be well sealed, and actual ducts must be used – chases and floor cavities should not be used as ducts.

The "trunk and branch" and "radial" supply duct configurations are most suitable for ducts located in conditioned spaces. Here are some common configurations:

To check for adequate return air capacity, try this simple test: close all exterior doors and windows, close all interior room doors, turn on the central air handler, and then "crack" interior doors one by one to observe if the door closes or further opens on its own.

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Modifying your air ducts and vents can be a great idea, especially if you're upgrading to a zoned HVAC system. This can be a good opportunity to update and modify your existing air ducts and vents.

You might choose to do this during a heat pump system installation, which can be a convenient and cost-effective way to upgrade your ductwork.

Modifying your air ducts and vents can help improve airflow and efficiency in your home, making it a worthwhile investment for many homeowners.

Designing and installing a good air conditioning system is crucial for efficient cooling and heating. A well-designed system should provide balanced supply and return flow to maintain a neutral pressure within the house.

Air conditioning systems can be configured in different ways, including the "trunk and branch" and "radial" supply duct configurations, which are most suitable for ducts located in conditioned spaces.

To determine if your air conditioning system has adequate return air capacity, close all exterior doors and windows, close all interior room doors, turn on the central air handler, and then "crack" interior doors one by one to observe if the door closes or further opens "on its own." Rooms served by air-moved doors have restricted return air flow and need pressure relief.

A simple check for adequate return air capacity can be performed by observing how doors react to air flow. If doors close, it indicates good return air flow, but if they open, it suggests restricted return air flow.

Here's a quick summary of common air conditioning duct configurations:

These configurations are suitable for ducts located in conditioned spaces and can help maintain a neutral pressure within the house.

HVAC design problems can be a major issue, and it's essential to understand the common mistakes that can affect the performance of your air conditioning system. There are 4 common air duct designs, but flaws are all too common in HVAC air duct design.

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The plenum or radial duct system is one of the most common designs, where the HVAC unit and return grill are at the center of the home with supply ducts extending out around the plenum like the legs of a spider. This design can be problematic if not properly calculated.

Radial systems, like the perimeter loop system, can be a radial system with a supply duct that encircles the building, but this can also lead to issues if not installed correctly. Good HVAC contractors calculate airflow and determine the types of ducts to use to meet the home's requirements.

In an ideal world, there would be returns for every room of the house except the kitchen, bathroom, and utility room, but builders often like to save on costs. With only one central return duct to feed the HVAC unit, closed doors will starve the furnace or AC and create a negative pressure environment.

Dirty outside air then infiltrates the house through fissures, creating all sorts of pesky issues. This is a common problem known as the Central Return Problem.

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Central conditioning is a vital part of a well-designed air conditioning system. It removes heat and humidity from your home and places it outside.

The system then utilizes a series of ducts to re-distribute the newly cooled air throughout your home. This is made possible by the negative pressure in the ducts that sucks the air in, passing it through a filter.

A properly designed air duct system reduces noise levels and helps maintain even temperatures between rooms. This is especially important in homes with multiple rooms, as it ensures that the air is circulated evenly throughout.

Proper ductwork also allows for better airflow throughout your home, which in turn helps increase energy efficiency while lowering energy costs. This is a significant benefit for homeowners who want to save money on their utility bills.

With a well-maintained duct system, you can also enjoy improved indoor air quality. This is because the ducts help keep pollen and dust particles contained, allowing them to be captured by the filters and removed from the air.

Designing and installing an air conditioning system requires careful planning to ensure optimal performance and energy efficiency. A well-designed system can distribute air properly throughout your home without leaking, keeping all rooms at a comfortable temperature.

Proper duct system design is critical, especially in new home construction or retrofits. Energy-saving designs often include ducts and heating systems in the conditioned space.

In recent years, energy-efficient homes have placed the duct system within the conditioned space of the home. This can be achieved by hiding the ducts in dropped ceilings and in corners of rooms, or by locating them in a sealed and insulated chase extending into the attic or built into raised floors.

Regardless of where they are installed, ducts should be well sealed. Two common configurations for ducts located in conditioned spaces are the "trunk and branch" and "radial" supply duct configurations.

Air return duct systems can be configured in two ways: each room can have a return duct that sends air back to the heating and cooling equipment, or return grills can be located in central locations on each floor.

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Here are some tips for checking the return air capacity of your system:

By following these guidelines and paying attention to the return air capacity of your system, you can ensure that your air conditioning system is working efficiently and effectively.

Check your ducts for air leaks, looking for sections that should be joined but have separated and obvious holes. This is a crucial step in maintaining a healthy duct system.

Duct mastic is the preferred material for sealing ductwork seams and joints, as it's more durable than tape and easier to install. However, it won't bridge gaps over ¼ inch, so you'll need to use web-type drywall tape or heat-approved tape to fill those gaps first.

If you do use tape, avoid cloth-backed, rubber adhesive duct tape, which tends to fail quickly. Instead, use mastic, butyl tape, foil tape, or other heat-approved tapes with the Underwriters Laboratories (UL) logo.

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Here are some common issues to watch out for:

If you notice little or no air flow from your supply vent, it's likely due to a blockage or issue with the damper. You can easily check this by placing a piece of paper in front of the supply opening - if it doesn't bend, something is preventing airflow.

The damper on your register might be closed, which is an easy fix. Simply reopen it and see if that resolves the issue. If not, you may need to call an HVAC expert.

Supply ducts are responsible for pushing conditioned air into your home, while return air ducts pull unconditioned air into your furnace or air handler. To ensure proper airflow, make sure you're not blocking HVAC vents or registers with furniture, curtains, or covers.

HVAC duct design can also impact airflow. There are four common air duct designs, including the plenum or radial duct system, which can be prone to flaws in its design.

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In an ideal world, there would be returns for every room of the house except the kitchen, bathroom, and utility room. But builders often try to save on costs.

With only one central return duct to feed the HVAC unit, closed doors can starve the furnace or AC, creating a negative pressure environment. This can lead to dirty outside air infiltrating the house through fissures.

Builders often cut corners to save money, and it shows in the quality of air duct installations. Unfortunately, this can lead to a host of problems down the line.

A single central return duct can't handle the airflow needs of an entire house, especially if doors are closed or furniture blocks the return vents. This can cause the HVAC system to work harder, leading to increased energy bills and a shorter lifespan.

In many cases, it's not just the ductwork that's the problem, but the way it was installed. If you suspect your duct work is designed or installed improperly, it may be the root of all your heating and cooling dilemmas.

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Air conditioning ducts come in a variety of materials, each with its own unique characteristics.

Traditionally, air ductwork is made of sheet metal, but modern manufacturing techniques have introduced new options like rigid insulation panels made from polyurethane or phenolic foam.

These panels have factory-applied aluminum facings on both sides, with a thickness ranging from 25 micrometers for indoor use to 200 micrometers for external use or higher mechanical characteristics.

Rigid phenolic insulation ductwork systems are listed as a Class 1 air duct to UL 181 Standard for Safety, providing an added layer of assurance for building owners.

Fiberboard ducts, on the other hand, are compressed and resin-bonded fiberglass laminated with a foil sheet, protecting them from moisture.

However, fiberboard ducts are not recommended for ventilation systems due to the potential for mold and bacteria growth.

Fiberglass-lined ducts have internal or external fiberglass lining, making them a popular choice for commercial buildings and offices, but they can deteriorate and release small particles of fiberglass into the air.

Fiberglass Board is a popular choice for air conditioning ducts due to its built-in thermal insulation.

Fiberglass duct board panels can help provide quiet operation of the HVAC system by absorbing sound.

The interior surface of fiberglass duct board panels absorbs sound, making them a great option for homes where noise reduction is important.

Fiberglass duct board panels are formed by a process that involves sliding a knife along the board to create a groove with 45° sides.

This groove serves as a hinge, allowing the duct board to be folded into a rectangular shape in the desired size.

The folded duct is then closed with outward-clinching staples and special aluminum or similar metal-backed tape.

Fiberglass duct board panels are a cost-effective and efficient option for air conditioning ducts.

However, it's worth noting that fiberglass duct board panels can become a home to mold and bacteria if not properly maintained.

Fiberglass duct board panels are not recommended for ventilation systems due to this risk.

Air ducts are made of thin material with little insulating capacity. This means they can't keep the air inside them at the right temperature.

In the summer, insulation prevents cool air condensation that can lead to mold and mildew. This is especially important in unconditioned spaces like attics and crawl spaces.

The recommended air duct insulation level in these areas is R-8. Most air ducts, however, are only insulated at R-2, which is woefully inadequate.

Polyurethane and phenolic insulation panels are a game-changer in air ductwork. They eliminate the need for additional insulation and can be installed in a single step.

Traditionally, air ductwork is made of sheet metal, but polyurethane and phenolic foam panels can replace this with factory-applied aluminium facings on both sides. The thickness of the aluminium foil can vary from 25 micrometres for indoor use to 200 micrometers for external use or for higher mechanical characteristics.

Some rigid polyurethane foam panels are made with water as the foaming agent, replacing CFC, HCFC, HFC, and HC gasses. This makes them a more environmentally friendly option.

A rigid phenolic insulation ductwork system is listed as a class 1 air duct to UL 181 Standard for Safety. This is a significant advantage for installers and building owners.

PVC low-profile ducting has been developed as a cost-effective alternative to steel low-profile ducting.

Low-profile ducting has been used extensively in apartment and hotel ventilation since 2005.

The growth of low-profile ducting has grown significantly due to the reduction of available space in ceiling cavities in an effort to reduce cost.

Since the Grenfell Tower fire in 2017, many PVC low-profile ducting manufacturers have struggled to gain or maintain compliance.

Some building projects have had to resort back to using the more expensive steel option.