This will prevent any possibility of rust or erosion.
Where should screws be installed in metal roofing.
Your roof will have thousands of screw holes.
Most manufacturers drill holes through the corrugated metal roofing sheets.
However you have to ensure the rubber washers have enough space to move around.
Screws that are installed in the low of the metal roofing panel will result in a more secure connection but will be less weather tight.
Metal roofing installation requires special metal roof screws that are equipped with a metal washer with a neoprene seat on the base of the washer.
You will want to note your metal roof screw pattern so you know where to look for potential problems.
Quite often the screws are over tightened or under tightened and when this happens it creates leak points.
Corrugated roof panels and other exposed fastener metal roofs are usually held together with screws every 18 inches or 2 feet.
Absolute steel advises screws be installed down inside the flat of the panel and not in the top of the rib.
Working with metal siding and roofing will often create gaps when the screws are inserted into the metal.
See the illustration below.
These are where to screw down corrugated metal roofing.
As the screws are driven the washer presses against the metal roofing to form a water proof seal.
The screw will compress better when attached in the low and you are less likely to distort the metal roofing panel when you tighten the screw.
These screws must be installed at the proper.
Find roofing screws with either manufactured rubber caps or washers that will create a proper seal.
Align the first metal roofing panel so that it overlaps the edging by 1 2 to 3 4 of an inch and is square to the roof line.
Be sure the larger edge is laid so that the small edge of the next panel will overlap it.
Install the roofing screws vertically along each rib in the panel.
Today the fasteners of choice for corrugated roofing are gasketed hex head screws with a metal and rubber washer below the head.
This can potentially cause damage in the future.