For the most part, people who get metal roofs put onto their homes or commercial buildings are concerned with precipitation and other weather or debris that comes from above the building. However, there is also the risk of moisture and snow getting in through the gap at the bottom of a roof. That is why a skilled metal roofer makes sure to install roof cappings to make sure the job is truly done.
The roof ridge is covered only after all the roofing panels are installed and fastened. A ridge-sealing element is installed to prevent snow from being blown in and to keep out the moisture. The ridge capping is fastened with self-tapping screws at every 12.5" at the peaks of the waves. After fastening the ridge capping, its ends are capped.The diameter of the ridge capping must be a minimun of 9" to establish proper ventilation in the attic. This allows for the free flow of air in the attic to prevent the trapping of hot, moist air and condesation.