What Is A Purlin?

In architecture and structural building, a purlin is a horizontal beam used as structural support in buildings. Purlins are supported either by rafters or the walls of the building. They are most commonly used in steel structure building. Purlin is important because without it, there is no frame for the sheeting on the roof to rest on, making purlins critical to the structure of the roof.

1. What is Steel Purlin?

2. Purlin and Girt

3. Roof Purlin and Purlin Span

4. How to install Purlin and choose Purlin Supplier?

   
   

Steel Purlin

Steel Purlin is a direct replacement for wood purlin. They are light weight, dimensionally stable, accurate and straight.

Steel purlin is usually made of cold-formed steel profiles that is easy to put screws through. Though cold-formed steel is stronger than hot-formed steel, it is more likely to break when under pressure rather than bend.

Purlin and Girt

Secondary structure is an important component of prefabricated steel structure buildings. It runs in between primary framing elements, creating a structure-within-a-structure.

The purpose of secondary structure is to distribute loads from the building’s surfaces to the main steel structure and the foundation. Secondary framing can add longitudinal support that helps resist wind and earthquakes. And it can provide lateral bracing for compression flanges that are part of the primary framing, increasing overall frame capacity.

Purlin Roof

Roof purlin is subjected to dead load (e.g self weight of roof materials and accessories), live load (e.g. during maintenance services and repairs), and environmental loads (e.g. wind and snow load). Therefore, a purlin should be adequately strong to withstand the loads it will encounter during its design life and should not sag in an obvious manner thereby giving the roof sheeting an undulating and/or unpleasant appearance. This post will be focusing on design of steel purlin using cold formed sections.

Purlin Span

Each span type represents a complete purlin run system and recognizes that using separate component parts (e.g. internal span, end span) is not a valid procedure.

Single Purlin Span

Single purlin span is the span that is simply supported by means of bolting the web of the purlin to a cleat or other rigid structure.

Double Purlin Span

Double purlin span are simply supported at each end and in the center. They may comprise only one purlin over the full length or two purlins lapped together over the central support to provide continuity.

Continuous Purlin Span

Continuous purlin span are simply supported at each end and at a series of equally spaced intermediate supports. These tables are for spans in which purlins are lapped over each support.

Purlin Installation

Purlins are installed horizontally under steel roofs. They are installed on top of the roof beam. They give added support to the roof and also provide a nailing surface for the end sheeting/panels and trims.

Purlin Supplier

Last but not least, you have to choose the best supplier for you to order purlin. A reputable supplier with strong customer base can ensure the purlin’s quality to a certain extent.

Production Capacity

Production capacity of the manufacturer decides how long it takes you to receive the purlin. The higher the production capacity is, the shorter time you have to wait. In general, big manufacturer have higher production capacity.

Professional Sales

If you are looking for a foreign supplier, they are needed to be familiar with exporting activities. You had better work with knowledgeable sales, which will push the process going much faster.

After-sales service

After buying purlin, you still need assistance in setting and maintenance. You will be in trouble if your supplier disappears right after sales because there will be no one to guarantee the quality of the products and take responsibility when they are faulty.

Service

Payment: T/T.

Package: Steel pallet for Purlin

Delivery time: 20-35 days after receiving the deposit.

Communication: 24/7 hotline, 24/7 email and website. Your inquiry will be replied in 24 hours.

Consult: free 24/7 consult.