Metal roofs are often chosen because they are considered durable and longlasting. While this is true, it doesn't mean they are impervious to damage or leaks. The following guide can help you recognize leaks early and provide you with information on repairing the damage.
Common problem areas
There are a few areas on a metal roof that are more likely to develop a leak, so these are the areas you should make a point of inspecting at regular intervals. Possible locations include the following:
Areas around vent stacks and roof pipes. Each time something protrudes from the roof, a seam is required in the roofing. Often, it is the caulking around these seams, not the metal roofing, that gives out and begins to leak.
Skylights. Much like vent stacks, it's the seams around skylights that develop leaks. Skylights also often protrude somewhat from the roof, which can lead to water collecting at the upper edge and weakening the seal more quickly.
Valley flashing. The flashing installed in roof valleys is there to protect against leaks, but occasionally the flashing gets lifted and water is able to flow beneath. Bends in the metal flashing are more likely to occur during a storm, so perform a quick visual inspection each time the clouds clear.
There are several repair options, depending on the cause of the leak and how long it has been going on. For leaks that occur because of damaged flashing, the fix is generally to repair the flashing. Seam leaks will require the removal of the old caulk and application of new caulk. Before either of these repairs are completed, though, the roofer will lift the metal roof panels and make sure that the underlayment hasn't suffered damage or begun to rot. If it has, then you may need to have new roof sheathing installed – at least in the damaged area.
In some cases the leaks are occurring around the installation nails that are holding down the metal roof panels. When this is the case, a silicone sealant is applied around each nail where leaks are occurring. Another option is to have a metal roof coating applied, which will provide a membrane against leaks. These coatings are clear, so they don't affect the appearance of your roof, but they add an additional barrier against moisture.
For more help, contact a metal roofing contractor in your area. They can help you find and repair the leaks.