Why is screw spacing important?
Proper metal roofing installation begins with the use of the right equipment, starting with the screws used to anchor your panels to the structure.
You must make sure you are placing the screws in the appropriate place for a tight fit so that the panel is able to resist specific loads.
All fasteners must be in accordance with the drawing displayed in the Florida Building Code Permit since each design is wind-load specific for each panel. Failure to do so, will result in a failed inspection; therefore, no permit = no metal roof = your roof being destroyed in the first storm
Exposed Fastener Panels
Exposed fastener panels are fastened down 1 or 2 ways. The FL-Product approval will usually display more than one anchor pattern, usually labeled anchor pattern A and anchor pattern B.
Anchor pattern A is a standard screw pattern, whereas, B is a tighter screw pattern for higher wind loads.
This will be different if you are using an aluminum panel, in which case the fasteners should be placed in a much tighter pattern.
Hidden Fastener Panels
Hidden fastener panels, also known in the metal industry as “standing seam” panels, are considered more aesthetically pleasing to some simply because of their hidden-screw profile.
Some require clips which are concealed anchors that attach a metal panel to the substrate with the use of fasteners. The panel systems which require these are designed to be able to expand and contract without issue, since the panels are not anchored to the structure directly through the metal to the roof deck. These would especially need to be attached per the manufacturer’s instructions and/ or the FL-approval!
Some standing seam panels (like ours) do not require a clip system, but rather, a screw-flange for fastening the panels down. These panels and their trim are fastened a bit more tediously, compared to a clip system or an exposed fastener panel, simply to achieve the hidden fastener goal. To do so, trim such as: Z-closures, gable cleats, and offset cleats are used. For everything to be fastened properly, these trim pieces must in the appropriate places and, more importantly, be anchored correctly since they are what holds everything into place without the need for all sorts of screws everywhere -- thus, you have a hidden fastener system!
Contact a sales rep at 1st Coast Metal Roofing Supply for further assistance on screw patterns!