Asphalt shingles have been used to cover roof slopes 2:12 and greater for over 125 years, but they’re not always installed the same way. Although the industry allows the employment of different installation methods, experienced installers would agree that some methods prevent leaks better than others.
As a licensed roofing contractor, Napolitano Roofing expounds on how asphalt shingles are usually applied to roof planes and valleys:
Laddering – Installing shingles in a “ladder” pattern means nailing the materials straight up, starting from the eaves all the way to the ridge. It involves leaving either the left or right shingle tab unsecured to make it possible to interweave the following courses into those already fastened. Also called “racking” or “staggering”, this method is not usually recommended by many manufacturers. Although it’s widely considered acceptable, it has gained a reputation for increasing the chances of failure. With proper installation and roof maintenance, it can make for a watertight covering, but it can also lead to pattern-curling and shadowing.
Stair-Stepping – The traditional stair-stepping method is all about installing shingles in different courses, overlapping one another to form a “stair” pattern. Nails are always applied along the edges of each “stair”, which promises better wind resistance.
Closed – In this construction, the shingles cover the valley, which is the section where two roof planes intersect. Extending across the valley and onto adjacent roof planes, the shingles protect the underlying lining, which is either a thick underlayment or a thin piece of metal. Although it promises a clean look, it tends to have drainage problems. Reliable providers of roofing services experts would say that debris could get into and clog the narrow passages underneath the shingles, trapping water in the process.
Open – Open valleys are uncovered by shingles. Instead, they’re waterproofed by another layer of lining. The most popular material is metal because it weathers well, especially the rustproof kind. In this construction, the water and any debris can flow freely all the way to the gutters.
As a GAF-certified roofer, Napolitano Roofing knows what it takes to nail asphalt shingle installation. Call us at (860) 265-4001 to talk about your roofing needs and get a FREE estimate in Vernon, Manchester, Glastonbury or any nearby Connecticut community.