Oval Ducts From AGI: Better Airflow in Tight Spaces

High-Performance Oval Ductwork: The Space-Saving HVAC Solution

Space constraints shouldn’t force you to compromise on HVAC performance. When your project faces limited plenum heights or congested ceiling spaces, oval ductwork offers a practical solution that combines the superior airflow characteristics of round ducts with a compact profile.

AGI Fabricators builds custom oval ductwork that tackles four common challenges in commercial and industrial HVAC design:

Space efficiency where it matters. Oval ducts provide comparable airflow capacity to round ducts while requiring significantly less vertical clearance. This makes them ideal for retrofitting older buildings, working around existing infrastructure, or maximizing floor-to-ceiling heights in new construction.

Better airflow, lower energy costs. The curved surfaces of oval ducts create less resistance than rectangular alternatives, reducing static pressure drop by up to 50%. Your fans work less, your energy costs drop, and your system performs more efficiently over its entire lifespan.

Significantly reduced air leakage. Our precision-fabricated oval ducts achieve leakage rates as low as 1-2%, compared to 10%+ for typical rectangular systems. This translates directly to better system performance and lower operational costs.

Quieter operation for occupant comfort. The rigid structure of oval ducts minimizes vibration and the “oil canning” effect common in rectangular systems. The result: noticeably quieter HVAC operation in noise-sensitive environments like offices, healthcare facilities, and classrooms.

AGI’s Custom Fabrication Advantage For Oval Duct Solutions

Since 1893, AGI Fabricators has specialized in solving complex airflow challenges through precision metal fabrication. Our approach to oval ductwork combines proven engineering principles with custom manufacturing capabilities you won’t find elsewhere.

Custom sizes for exact project needs. Through specialized die technology, we produce oval ducts in dimensions beyond standard offerings. This means we can match your exact requirements for both major and minor axes, helping you navigate even the most challenging spatial constraints.

Material selection matched to application. We fabricate oval ducts in:

• Galvanized steel for standard commercial applications
• Stainless steel (304, 316) for facilities with special hygiene requirements or corrosive environments
• Aluminum for lightweight applications or areas with specific corrosion concerns

Construction built for durability. All our oval ductwork is manufactured to SMACNA standards, with options for spiral lockseam or longitudinal welded seams based on your pressure class requirements. For larger sizes or higher pressures, we incorporate appropriate reinforcement to maintain dimensional stability.

Oval Duct Technical Specifications At-A-Glance

Performance Advantages of Oval Ductwork

When comparing AGI’s oval ductwork to traditional rectangular systems, the benefits become clear in several key performance areas.

The inherent aerodynamic properties of oval ductwork create significant airflow advantages. As noted in industry comparisons, the curved surfaces of oval ducts produce substantially lower static pressure drop compared to rectangular alternatives. This reduced resistance means HVAC fans don’t need to work as hard to move the required volume of air through the system. The practical result is reduced fan energy consumption and lower operational costs over the system’s lifespan.

Space efficiency stands as perhaps the most compelling advantage. Oval ducts deliver airflow capacity comparable to round ductwork while requiring substantially less vertical clearance. This makes them ideal for buildings with restricted plenum heights or congested overhead spaces. Projects that might otherwise sacrifice ceiling height or struggle with complex routing around existing infrastructure can maintain optimal airflow without compromising spatial design.

Air leakage, a persistent challenge in HVAC efficiency, is dramatically reduced with properly manufactured oval ductwork. While traditional rectangular systems have historically struggled with leakage rates exceeding 10%, spiral-seamed oval duct systems can achieve leakage rates as low as 1-2%. Some specialized systems can reach even lower rates of 0.5% when pursuing LEED credits. This improvement in air tightness ensures conditioned air reaches its intended destination rather than escaping into unconditioned spaces, which can waste up to 30% of energy in poorly sealed systems.

The structural characteristics of oval ducts also contribute to quieter operation. The curved surfaces are inherently more rigid and less prone to the vibration and “oil canning” effect often associated with the large, flat surfaces of rectangular ductwork. The result is reduced breakout noise and a more comfortable acoustic environment for building occupants. This makes oval ductwork particularly valuable in noise-sensitive settings such as offices, healthcare facilities, and educational institutions.

Installation efficiency represents another significant advantage. AGI’s oval duct sections can be manufactured in longer continuous lengths (up to 12ft) than typical rectangular segments, resulting in fewer field joints. Fewer connections mean reduced installation time, lower labor costs, and fewer potential points of failure or air leakage. According to industry comparisons, projects using spiral duct systems (including flat-oval) may achieve installation cost reductions of up to 50% compared to rectangular alternatives, primarily through reduced labor requirements and simplified sealing processes.

For architects and designers, the aesthetic quality of oval ductwork offers additional value in exposed applications. The smooth, continuous lines present a more refined appearance than rectangular systems, allowing mechanical elements to complement rather than detract from interior design in open-ceiling concepts. This visual appeal has made oval ductwork increasingly popular in modern architectural designs where mechanical systems become part of the visible environment.

When these advantages combine—reduced energy consumption, space efficiency, improved air tightness, quieter operation, easier installation, and superior aesthetics—AGI’s oval ductwork emerges as a comprehensive solution for demanding HVAC applications that refuse to compromise on performance or design.

Getting Started with AGI

Partnering with AGI for your oval ductwork needs follows a straightforward collaborative process designed to deliver optimal results. The journey begins with an initial consultation where our team works to understand your specific project requirements, including any space constraints, airflow needs, and special considerations unique to your application. From there, our engineers develop a custom specification tailored to your project, recommending the most appropriate materials and precise dimensional specifications to address your challenges. 

Once approved, we move to the fabrication phase, where your custom oval ductwork is manufactured to exact specifications in our facility and in accordance with your project timeline. Our approach ensures you receive not just components, but solutions engineered specifically for your requirements.

Ready to solve your space-constrained HVAC challenges? Contact our team at (414) 438-6700 or visit agifabricators.com to discuss how our century-plus of fabrication expertise can benefit your next project. AGI Fabricators has been delivering custom metal solutions since 1893, and we’re ready to put that heritage to work for you.