Where to Place Screws on Metal Roofing Panels
Before starting any type of metal roof installation, you must know where to put the screws that will hold your metal siding panels together. There are many types of metal panels that have different headings and ends. Knowing where to place the screws that you will use for a particular installation can help you make the best decision about your home improvement project.
One of the most important factors in determining where to put screws is the screw pattern. The screw pattern for a single panel is called a purlin. The screw pattern for your entire metal roofing panel is known as a roping. Screws that are used in metal purlins will be spaced closely together. Spaced too closely together, the screws will not move as they are being installed and will not engage with each other.
The same concept works for metal roofing where there is a double panel. Each panel will have a solid wood veneer over a sheet metal roof. The screw pattern will be different for the double panels as well. The screw pattern will be different because it will be needed to allow a secure attachment to the wood veneer. If you have an improperly sized screw pattern, the screws could gap up between the wood and the sheet metal.
One of the reasons that it is so important to know where to put screws is because you cannot simply go buy a screw and hope that it will fit. When you buy a screw, there is a simple formula to determine its size. The formula is as follows: A + B where A is the diameter of the screw and B is the thickness of the material that it is made out of. For metal roofing, the diameter is usually 12 inches but you can calculate it based on what diameter of your screw will be. Remember, you are dealing with steel so the actual size may vary slightly.
The next thing that you need to determine for your metal roof screw pattern is spacing. Spacing refers to how far apart the holes in the panel are going to be spaced. In general, you should allow about six to eight inches of spacing on each side for the panels to lie flat against the roof.
You can also calculate the right places where to place screws on metal roofs by figuring out the slope of the roof. The greater the slope, the more vertical surface area you will have. It can actually be beneficial to install metal roofs with more vertical surface area because then you don’t have to use as much weight to hold everything up. Also, if you install your metal roofs on a sloping surface, you won’t have to deal with the problem of rain and snow entering the attic from the roof’s edge.