Industrial Exhaust Stacks - How They Work, What They Do, And More

Industrial Exhaust Stacks - How They Work, What They Do, And More


Complete ventilation systems often release exhaust through the roof of the facility where after-the-fan products protect the system from intrusive elements such as rain and leaves that can decrease airflow. Fabrications like No Loss Stacks, Rain Caps and Double Flap Exhaust Valves provide solutions for keeping your system clean without negatively impacting fan performance.


Rain Cap

The most common type of exhaust system used is the standard elbow. This elbow allows for easy airflow through the unit, but it also creates a potential problem when it comes to rainwater intrusion. Rainwater entering the elbow can cause damage to the fan blades, which could lead to expensive repairs. To avoid this issue, US Duct Products offer a rain cap option. These caps are designed to keep rain out of the elbow while allowing for good airflow.

Rain caps are available in galvanized and stainless steel.

No-Loss Stackhead

Another option is the no-loss stack. This design uses a series of baffles to direct the flow of air around the elbow. It keeps rain out of the elbow and prevents any back pressure from building up inside the elbow.

The no-loss stackhead eliminates the back pressure caused by the fan's resistance to air flow. This allows the fan to operate at lower speeds, which reduces energy consumption. The no-loss stack head is usually placed near the top of the central exhaust duct. It consists of a large pipe that surrounds the smaller central exhaust duct. Water falling through the larger pipe collects on the inside of the no-loss exhaust stack and flows out the bottom of the stack.

No-loss Stackheads are available in galvanized and stainless steel.

Flap Exhaust Valve

Finally, US Duct Products offer a double flap exhaust stack. This design consists of two flaps that extend outward from the elbow. They create a larger opening than a single flap would, so there is less chance of rainwater getting into the elbow. Flap exhaust valves are usually mounted vertically and are designed to open and close with the flow of air through the duct. This allows the air to pass through the valve while preventing any water droplets from entering the duct which prevents corrosion and reduces maintenance costs.

Flap exhaust valves are available in galvanized and stainless steel. Heavy and light gauges are available to accommodate the needs of your system. Typical connection ends are flanged. 


Good ductwork design combined with materials that can withstand the rigors of time and the environment will result in a long lasting system.

Properly designed exhaust stacks and air intake systems can help reduce emissions by capturing particulate matter before it enters the atmosphere. However, there are many factors that must be taken into consideration when designing these systems. For example, the size of the system, the type of engine being used, the location of the exhaust stacks, and the amount of space available all play a role in determining how well the system works.

The most common type of exhaust used on residential systems is a straight exhaust. This allows the exhaust to exit the house through the roof without any bends or elbows. However, if there is a problem with the fan, the exhaust may not flow properly.

To avoid this issue, a rain cap or no-loss stack should be added to the exhaust. These devices reduce the amount of air entering the fan and help keep the fan running smoothly.

For every type of application, US Duct Products offers the right exhaust ductwork to fit your needs.