What Every Architect Needs to Know About UFAD 

Architects and building designers face difficult decisions when developing a design for a new or retrofitted building. From ceiling heights to complex essential building systems, architects and developers are finding unique solutions to create a forward-thinking space. Among these unique solutions are underfloor air distribution (UFAD) systems.  

UFAD systems offer significant advantages over traditional HVAC systems and can be a great option for architects seeking to create an efficient, comfortable environment while maintaining an elevated design. An often-misunderstood solution for heating and cooling, UFAD can be overlooked due to myths. It’s important for architects and other building developers to understand the basic mechanics, benefits, and challenges of UFAD systems.  

What is UFAD? 

An underfloor air distribution system (UFAD) routes heated and cooled air through a plenum system housed underneath a raised access floor. As the air rises through the breathing zone, the return air is sent back in at the ceiling to remove warm air faster than traditional overhead VAV systems. Because the air is drawn upward through the room by its natural thermodynamic properties, the tempered air is distributed more evenly and consistently throughout the space. 

The raised access floor system allows for easy access, maintenance, or even upgrades as needed. Additionally, space in the raised floor area can be used to route other essential mechanical, electrical, and plumbing systems, saving overhead space. 

Benefits of a UFAD System 

UFAD systems can provide many benefits to an architect’s building design plans, from energy efficiency to architectural excellence,

• Energy Efficiency. Because they use thermodynamic properties, UFAD systems are highly energy-efficient climate control units. Improved energy efficiency can often help architects secure LEED, ENERGY STAR, and other sustainability credits and certifications, enhancing the project's sustainability and notability.

• Indoor air quality. Indoor air quality standards from governing bodies, including the EPA and ASHRAE, are consistently rising – and for good reason. With the majority of our days spent indoors, clean, healthy air is essential for workplace and personal safety. UFAD systems limit exposure to pollutants, including dust and pollen, with diffusers that capture particles by supplying fresh air at low velocity into the primary breathing zone. These systems are easy to maintain with clear access points for regular cleaning.

• Occupant comfort. The consistent supply of temperature-controlled air through a UFAD system, with strategically placed diffusers, provides a reliable temperature throughout the room. The diffusers reduce unwanted hot or cool spots, and gravity’s effect on heated air in the breathing zone allows for a constant replacement with fresh, tempered air. Because of these, UFAD systems can greatly increase occupant comfort.  

• Noise reduction. Traditional overhead VAV systems, while also an eyesore, are very loud. UFAD systems don’t rely on the same large fans and ductwork that make overhead systems so noisy. In fact, AirFixture’s UFAD systems are very quiet, rated at Noise Criterion level 18 – the most commonly used metric for measuring background noise in a space. 

• Architectural Aesthetics. Because UFAD systems are carefully hidden beneath raised flooring, architects and engineers can let their buildings shine. Overhead VAV systems cover a building's ceiling, leaving no room for eye-catching art or unique architectural features. By hiding essential building systems in the raised floor, architects can be more creative in their design. 

Challenges of Underfloor Air Distribution 

There are two challenges that UFAD can present, but they can be overcome with the right planning.

• Up-front cost. UFAD systems are a premium solution to traditional HVAC building systems. With premium quality comes premium prices. UFAD systems typically have higher upfront costs than traditional overhead systems. However, with long-term energy savings from their high efficiency, the upfront costs of installing UFADs balance out over time, making them more cost-effective for building owners. The initial investment in a UFAD system pays off in the long run. 

• Retrofitting. Because overhead HVAC systems have been the most popular option for decades, many existing buildings are already equipped with inherited systems. To install UFAD, spaces need to be retrofitted with raised access flooring, and existing air ducts need to be removed through demolition. This retrofitting can be costly during installation. 

Installation and Maintenance of UFAD Systems 

UFAD systems are quick and easy to install. Our trained MEP engineering professionals work directly with our clients to ensure easy access for future maintenance and upgrades. The raised flooring housing of the UFAD unit allows for safe and easy maintenance. Commercial UFAD providers often include maintenance guides or direct personal maintenance services to keep your system running smoothly. 

UFAD Guides and Resources 

Understanding UFAD and other essential building systems is paramount for architects and engineers to design efficient buildings of the future.

We've created a series of resources to help architects better understand how UFAD can be used:

• The Complete Guide to Underfloor Air Distribution: Key Elements and Common Mistakes When Implementing UFAD

• The Guide to Raised Access Flooring

Our support and sales teams around the world are on call to answer any questions about the process, design, installation, and customization of our products and to provide additional resources.