What Are Purlins In A Roof In Bracknell?

As a roofing company in Bracknell, A1 Roofing Bracknell understands the importance of the structural components that form the foundation of a sturdy roof. One such component that ensures the strength and durability of a roof is purlins. In this landing page, we will provide you with a comprehensive guide on what purlins are, their significance in a roof, and how they are used in construction.

Introduction

Purlins are horizontal structural components that support the weight of the roof deck and transfer it to the building's main frame. They are used primarily in steel and timber-framed constructions. Purlins run perpendicular to the rafters and the roof's slope, and they are fitted onto the ends of the rafters or trusses. They are placed along the length of the roof, typically between 0.6 to 1.2 meters apart, depending on the loads the roof will bear.

Types of Purlins

There are different types of purlins available in the market, and the choice depends on the type of construction and the design requirements of the roof. The common types of purlins used in construction include:

1. C Purlins

C purlins are made of galvanized metal and are commonly used in steel-framed structures. They are characterized by their shape, which resembles a letter "C." They offer superior tensile strength, making them suitable for buildings with a large roof span.

2. Z Purlins

Z purlins are also made of galvanized metal, and their shape resembles a letter "Z." They are commonly used in timber-framed constructions. They offer exceptional strength and stability, making them suitable for buildings with heavy roof loads.

3. Sigma Purlins

Sigma purlins are a variation of C purlins that are curved to form a "sigma" shape. They are more resistant to bending stresses and are commonly used in building curved roofs.

4. Box Beam Purlins

Box beam purlins are made of timber and come in rectangular or square shapes. They are best suited for traditional roofing systems and are often used in timber-framed or post-and-beam constructions.

Purlin Spacing

Purlin spacing refers to the distance between adjacent purlins on the roof. The spacing of purlins depends on the type of construction and the load capacity requirements of the roof. A standardized spacing for purlins in steel-framed buildings is 1.2 meters, while a spacing of 0.6 meters is used in timber-framed constructions. However, larger- span roofs may require closer spacing of purlins.

Purlin Overlapping

Purlin overlapping refers to the overlapping of two purlins to increase the strength and stability of the roof structure. When purlins overlap, they provide better support for the roof decking and reduce the chances of sagging between the supports. The overlap typically ranges between 150mm to 200mm and depends on the type of purlin used and the span of the roof.

Purlin Ends

Purlin ends refer to the positioning of the purlins at the gable and eaves of the roof. The purlin ends are supported by wall beams or plates to provide additional support to the roof structure. The purlin ends are secured to the wall with bolts or fixings, and the roof cladding is fixed to the purlins.

Pre-Drilled Holes

Purlins come with pre-drilled holes that make it easier for them to be fixed in place. The holes are typically 16mm or 18mm in diameter and are positioned at regular intervals along the length of the purlin. The holes are used to fasten the purlin to the roof frame using bolts or screws.

Sigma Purlin Web

A common characteristic of sigma purlins is their webbed design. The webbing provides additional strength and stability compared to other types of purlins. The webbing is designed to distribute the load across the entire frame, reducing the risk of bending or sagging.

Purlins in Building Construction

Purlins play a crucial role in the construction of residential, commercial, and industrial buildings. They support the roof structure, provide a base for the roof decking, and distribute the load across the entire frame. Purlins ensure that the roof remains stable and withstands the weight of the roof covering, rain, wind, snow, and any other loads it may bear.

Purlin Sections Available

Purlins are available in different sections and sizes, depending on the requirements of the building. The sections and sizes vary depending on the type of purlin and the load capacity requirements of the roof. The most common purlin sections available are C-sections, Z-sections, and Sigma sections.

Bansal Purlin

Bansal purlins are a type of steel purlin manufactured by Bansal Roofing Products Ltd. They offer excellent strength and durability and are commonly used in steel-framed constructions. Bansal purlins are available in different shapes and sizes, and they are designed to meet the specific requirements of the building.

Request Web Drilled Holes

Purlins with request web drilled holes are purlins that are customized to meet the specific requirements of the roof construction project. The holes are drilled-out to match the dimensions and spacing of the roof and to ensure the purlins are accurately positioned for maximum load support.

Round Purlin Holes

Round purlin holes are a type of pre-drilled holes used in purlins. The holes are circular and are available in different sizes, typically ranging between 12mm to 18mm. Round purlin holes ensure that the purlins can be easily and securely attached to the roof frame, providing a stable foundation for the roof structure.

Conclusion

At A1 Roofing Bracknell, we understand the importance of purlins in roof construction. They play a crucial role in providing support, strength, and stability to the roof structure. If you are in Bracknell, Berkshire, or the South East England region, and you need a reliable and competent roofer, don't hesitate to contact us. We are always available to provide you with expert roofing services that meet your specific needs. You can reach us by phone at 01344 534049 or by email at [email protected]. Visit our website at a1-roofing-bracknell.co.uk to learn more about our services and to get a free quote.