What size metal purlins do I need?
A four-inch purlin can span 12 feet. A six-inch purlin can span 18 feet. An eight-inch purlin can span 25 feet. A ten-inch purlin can span 30 feet.
How thick should purlins be?
Purlins are 2” think wooden strips, which are laid on edge, while laths are up to 1” thick and are laid flat. Purlins should be preferably 2″ x 2″ or 2″ x 3″ rough. 1″ x 3″ purlins are inadequate; their use should be discontinued.
What is the maximum spacing for purlins?
The maximum distance between purlins is five (5) feet on center. If your building site is in a region that is prone to heavy snow loads or high winds, then we may place your purlins closer together for added strength.
What kind of wood do you use for purlins?
Kiln-dried softwood is recommended for purlins or decking (pine, fir, hemlock, and spruce). Hardwoods are difficult to fasten into without splitting and contain tannic acids that are corrosive to metal panels.
Can a 2×4 be used for purlins?
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.
What does Z purlin look like?
Z purlins resemble the shape of a letter “Z” and are also referred to as Zee or Zed purlins. They are roof framing members that span parallel to the building eave and support the roof decking or sheeting. The metal purlins are in turn supported by rafters or walls.
What are Z beams used for?
Z-sections are common structural components used for support. These steel struts are typically roll formed because they are used in construction, transportation and manufacturing industries where accurate dimensions are required.
What screws to use for purlins?
OMG Purlin Fasteners are designed for attaching single-ply membrane systems to structural steel purlins (12-18 gauge) in standing seam metal roof retrofit applications.