How far apart do you put purlins?

The purlin are ultimately used to fasten the roof steel providing a diaphragm effect, along with the siding, when properly engineered and installed. Spacing is typically 24″ on center in low snow loads and is reduced based upon truss span and snow load.

How do you layout purlins?

Lay the first purlin at the ridge of the roof down to the chalk line beginning at either corner. Fasten the purlin with 16d common nails into each vertical rafter. Insert two equally spaced nails into the rafter. The rafters are generally spaced every 16 inches on center.

How far can 2×6 purlins span?

A 2×6 spaced 16 inches apart can span a maximum distance of 13 feet 5 inches when used as a rafter, 10 feet 9 inches when used as a joist, and 6 feet 11 inches when used as a deck beam to support joists with a 6-foot span.

How far apart can you space trusses on pole barn?

Pole barn construction spaces the trusses 8 feet apart – or even up to 12 feet apart depending on the building design. With traditional stick-frame construction, the trusses are usually spaced 2 feet apart.

What size purlins do I need?

The sizes are as follows: A four-inch purlin can span 12 feet. A six-inch purlin can span 18 feet. An eight-inch purlin can span 25 feet.

Is Z purlin stronger than C purlin?

Z purlins are much stronger than C purlins due to its continuous or overlapping capability. In this case, for the metal building with bigger roofing loading capacity.

How far apart should Pole Barn Posts be?

When building a pole barn, the column spacing is dictated by a variety of different elements. Typically, they are built between 6-12 feet apart. Closer spacing is usually done if the barn is a bit smaller or if the ground isn’t as stable.

How far can 2×8 purlin span?

Max. Live Load 60 lbs/ft2 (2873 N/m2)
Maximum Span (ft – in)
Nominal Size (inches)Joist Spacing Center to Center, OC (inches)Lumber Grade
2 x 81215′ – 0”
1613′ – 7”
2411′ – 7”

How far can Z purlin span?

the maximum length of the fascia purlin fp23019 is 15000mm. length tolerance for all sections is ±5mm. lysaght Zed and Cee sections are delivered in strapped bundles.

Where do you use C purlins?

C purlins are used as purlins over walls, rafters, floor joists and studs for walls. Z purlins : Z purlins resemble the alphabet Z and are also called as Zed Purlins. This shape helps the purlins to overlap joint and is stronger and studier than the C purlins.

What is the most common spacing for rafters?

Builders aren’t bound by standard rafter spacing measurements. But they do tend to space rafters in one of several industry-standard increments, typically either 12, 16 or 24 inches apart.

Which way do Z purlins go?

When placing Cee purlins into a roof the purlin should be bolted to the top side face of the cleat with the open C facing up the hill. With Zeds or Z section the purlin should be bolted to the lower side of the cleat with the upper flange facing up the hill.

What length do C purlins come in?

Metroll offer a range of purlins and girts from 100mm to 400mm in Z and C profiles, cut to length, un-punched or punched. All purlins and girts are manufactured from high tensile, G450, G500 or G550 galvanised steel, with a minimum Z350 coating.

What is the length of C purlins?

The standard length of C purlins is 6 meters.

How far can you span C channel?

8″ C will span 25′, 6′ will span 20′.

What is the proper orientation of C purlins?

The best orientation for a purlin is straight.

How do you attach purlins to metal trusses?


Metal zee purlins should overlap on top of a truss. They should be placed on the outside of the truss clip with the bottom leg of the zee pointing toward the sidewall of the structure. The outermost truss clip will need to be adjusted for a vertical alignment.

How much do Z purlins cost?

Compare8″ X 2-1/2″ – 20′ 14GA PRIMED C PURLIN
8″ X 22′ Z-PURLIN
Our Price: $86.46

How far can a 2×4 purlin span?

2×4 purlins may also be nailed on top of the rafters with one 60-d nail or attached with metal clips at each rafter. Rafters may be spaced up to twelve feet, dependent on purlin size, when purlins are turned edgewise.

How do you install purlins on a metal roof?

What Is a Zee purlin?

Z purlins or zed purlins are horizontal beams that are designed to form the roof and wall joists of a building shell structure (also view our C section purlins page). They sit between the roofing sheets and the building, acting as a support for the sheet to ensure it is firmly attached and safely in place.

How thick is Z purlin?

Z-section steel is a common cold-formed thin-walled section steel, with a thickness of 1.6-3.0mm and a section height of 120-350mm. The processing materials are hot rolled (painted) and galvanized. Z-section steel is usually used in large steel structure plants.