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Roof Dunnage Explained

Roof dunnage provides structural support to roofs for items such as HVAC and generators. Continue reading to learn more.

Roof Dunnage

You’ve likely noticed heavy operational equipment, such as air conditioning cooling tower systems, and generators located on rooftops. Did you know that those pieces of equipment oftentimes require support in addition to the rooftop’s membrane? Continue reading to learn more about this structural support, also referred to as rooftop dunnage or simply, roof dunnage.

What is Roof Dunnage?

Roof dunnage ensures structurally sound support and security for large and valuable rooftop items. Often, builders make these structural supports from steel and connect them to cross beams or roof trusses. They will then place the equipment on top of the supports. Roof dunnage preserves the integrity of the building below by spreading the weight of the equipment over a larger space.

Benefits of Roof Dunnage

Roof dunnage provides more benefits than just structural support. It also allows for more airflow to the valuable equipment it holds which prevents overheating. This holds special significance in the context of HVAC systems. Positioning the unit too near the rooftop can result in reduced system efficiency and cause critical components to fail prematurely.

Roof Dunnage equipment sits on a raised surface of the ground. This prevents rain or other liquid from accumulating and potentially impacting the equipment's performance. Keeping high-priced electrical components dry and running in top condition is of utmost importance!

Supporting Structures of Roof Dunnage

Along with the rooftop dunnage itself, platforms are often built around the equipment for technicians to gain safe access for installation and maintenance. The platforms are typically built with a mixture of Bar Grating, Plank Grating, and Fiberglass Grating. These specialty metals bring safety, strength, durability, and character when installed in either industrial or architectural applications.

When steel dunnage is being created, stainless steel or galvanized steel is usually selected for its corrosion-resistant qualities. The products are also used to span intermediate rooftop supports as walkways from rooftop access points to equipment and back.

Securing Rooftop Items

Once the roof dunnage, supporting structures, and operational equipment are in place on a rooftop, securing the equipment comes into consideration. Around many roof dunnage systems, you will find metal enclosures protecting the equipment.

These metal enclosures are usually built using Expanded Metal or Wire Mesh. Expanded Metal is the more secure of the two because of its sharp edges and the way it is constructed and is used commonly for creating screens, security panels, and machine guards. Wire Mesh is more aesthetically pleasing and would be used when theft or vandalism aren't major concerns.

Your Rooftop Dunnage Project

If you are in need of HVAC dunnage or are managing a dunnage construction project as a steel fabricator or general contractor, McNICHOLS has the products to assist you. As the nation’s leading supplier of specialty metals products, we can provide the Grating, Expanded Metal, Wire Mesh and Accessories you need when you need them.

We are ready and Inspired to Serve® you at 855.318.8791, [email protected], or via Live Chat on