What is ridge capping in roofing?
Asphalt shingle roofs
Most Georgia homes use hip and ridge cap shingles made by the same manufacturer as the field shingles. They are thicker than regular shingles and come pre-scored or pre-bent, with color matched versions for each shingle color. Older roofs often have caps cut from 3-tab shingles, which works with 3-tab but not with laminated architectural shingles, which crack when folded. Manufacturers generally want their own cap product used for their system warranties.
Metal roofs
Metal roofs use a formed ridge cap, a bent piece of the same metal and finish, fastened over closure strips. The closures, solid foam or vented, are shaped to the panel profile and block wind-driven rain, insects and birds. On standing seam roofs the cap often attaches with concealed clips; on exposed fastener panels it is screwed through the high ribs.
Tile and slate
Clay and concrete tile roofs use cap tiles. Traditionally they were bedded in mortar and the joints pointed, and that is still common in some regions; newer practice often uses a ridge board, a breathable ridge roll and mechanical fasteners instead. Slate roofs use slate saddle ridges or a metal cap, often copper.
What every type has in common
- It covers the weakest joint on the roof, where two slopes meet.
- It often sits over ventilation, so it must breathe without leaking.
- It takes the most wind and the most direct hail of any part of the roof.
For how the cap fits the rest of the system, see roof anatomy explained, and for metal specifics, see metal roofing in Georgia.