All You Need to Know About Different Types of Purlins

Types of Purlins: Exploring Structural Roofing Elements

Purlins are horizontal structural members that provide support to the roof deck and transfer the load from the roof covering to the main roof beams or rafters. They are an essential component of roofing systems and help distribute the weight evenly across the roof structure. In this article, we will explore different types of purlins commonly used in construction.

1. Steel C Purlins

Steel C purlins, also known as channel purlins, are widely used in commercial and industrial buildings. They have a distinctive C-shaped profile and are made of galvanized steel for added strength and corrosion resistance. Steel C purlins are lightweight and easy to install. They are often used in large-span roof structures and provide excellent load-bearing capacity.

2. Steel Z Purlins

Steel Z purlins, also referred to as zed purlins, have a Z-shaped profile. They are similar to steel C purlins but with flanges that extend in opposite directions, forming the shape of the letter Z. Steel Z purlins offer increased strength and rigidity, making them suitable for heavy-duty applications. They are commonly used in industrial and agricultural buildings.

3. Timber Purlins

Timber purlins are wooden structural elements used in traditional and residential construction. They are typically made of solid timber or engineered wood products, such as laminated veneer lumber (LVL) or glued laminated timber (glulam). Timber purlins provide a natural and aesthetically pleasing option for roof support. They are commonly used in residential buildings, barns, and agricultural structures.

4. Aluminum Purlins

Aluminum purlins are lightweight and corrosion-resistant, making them suitable for structures in coastal or high-moisture environments. They offer excellent durability and require minimal maintenance. Aluminum purlins are commonly used in commercial buildings, carports, and lightweight roofing systems.

5. Composite Purlins

Composite purlins are a combination of different materials, such as steel and wood, to capitalize on their respective strengths. These purlins offer a versatile and efficient solution, utilizing the benefits of multiple materials. Composite purlins are often used in projects that require specific load-bearing capacities or where a combination of materials is desired for cost-effectiveness or design purposes.

6. Cold-Formed Purlins

Cold-formed purlins are made by roll-forming thin-gauge steel coils into the desired shape. They are commonly used in light-framed construction, such as residential or small commercial buildings. Cold-formed purlins are lightweight, cost-effective, and easily customizable to meet specific project requirements.


Purlins play a crucial role in providing structural support and load distribution in roofing systems. Whether you opt for steel C purlins for their strength, steel Z purlins for heavy-duty applications, timber purlins for a traditional aesthetic, aluminum purlins for corrosion resistance, composite purlins for a combination of materials, or cold-formed purlins for light-framed construction, selecting the appropriate type of purlin depends on factors such as the building’s design, load requirements, and environmental conditions. Consulting with a structural engineer or construction professional is recommended to determine the most suitable purlin type for your specific project.