How far can a SIP panel span?

 A common question we get asked at Formance is “how far can a SIP panel span?” 

It’s an important question because regardless of design, a far span means you can reduce additional structure in the project and have a nice interior space that is open and interrupted, like a skillion or cathedral ceiling.

The short answer is that the max a Formance SIP panel can span is 8.1m. This would be a 315mm panel with 63mm LVL13 splines and would only span that far if it was in a medium or less wind zone, with light roofing and no snow load (refer table 7.6 in our guide).

Our most common roof panel thickness is 215mm as it’s a great product for balancing cost, thermal performance and span. In most of Auckland, our 215mm panel can span around 5m with timber splines, and around 3m with thermal splines. The key site factors that impact the span of roof panels are wind zone, snow loading & roof pitch.

Refer to the Formance Design Guide for how far our panels can span on your specific project. We have 12 pre-engineered span tables that are CodeMark certified and allow you to specify our roof panels without needing specific engineered design (SED). 

Often when people think about reducing the span of a roof panel, they think of large supporting beams that need to impede on the ceiling space, but experienced designers and professionals know that they can utilize other parts of the building to reduce the panel span. Common ways of doing this are by making the internal walls load bearing, or flipping the orientation of the panels and using portals instead of ridge beams, or by using exposed trusses on the inside of the envelope. 

Regardless of how far you want your roof panel to span, it’s a good idea to reach out directly to Formance as we can help optimize your design to fit with SIPs and ensure that you’re getting the best value for your investment.