ridge course
The last or top course of roofing materials, such as tile, roll roofing, shingles, etc. that covers the ridge and overlaps the intersecting field roofing.
ridge course: the final row of roof covering at the peak
The ridge course is the uppermost run of roofing material that caps the peak where two roof slopes meet. It sits on top of and overlaps the field roofing (the main expanse of the roof) on both sides, sealing the apex against weather. This course is essential: without it, wind-driven rain and snow melt penetrate directly into the roof structure and attic space.
Ridge courses differ by roofing type. On asphalt shingle roofs, ridge shingles are three-tab or architectural shingles cut or folded to span the peak; they typically overlap 5 to 7 inches and are nailed or adhered on both sides. Clay or concrete tile roofs use specialized ridge tiles, often half-round or angled, that are bedded in mortar or occasionally clipped and nailed. Roll roofing systems use strips folded and sealed along the ridge. Metal roofing employs metal ridge caps, often with foam closures to block wind uplift and critter entry.
Installation quality directly affects longevity. Shingle ridges fail when fasteners are driven too high and penetrate into overlaps, or when nails miss the nailing zone and fasten only to the top shingle. Poor adhesion or gaps between field shingles and ridge pieces allow water and wind under the overlap. On tile roofs, ridge failures occur when mortar deteriorates or tiles crack from thermal movement; replacement without proper pointing leads to repeated leaks. Fastener rust and corrosion also compromise seal integrity over 15 to 25 years.
Ridge ventilation and closures
The ridge is a pressure point in attic ventilation systems. Traditional open ridge ventilation lets air exit from soffit intakes, improving attic moisture control. However, this requires proper closure strips or netting to prevent wind-driven rain and insect intrusion. Solid ridge courses block ventilation entirely, requiring soffit and gable vents to be proportionally larger. Some systems use specialized ridge vent products: porous foam strips, perforated plastic baffles, or vented metal caps that balance moisture escape with weather protection.
The term "course" comes from masonry tradition: a horizontal layer of units. In roofing, it retains this meaning even though ridge courses are often single or paired elements rather than full-width rows. The ridge itself is named for its sharp peak geometry, from the Old English word for a raised edge or backbone. Understanding the ridge course's structural and thermal role helps explain why leaks near the roof peak are so common and why ridge replacement is a frequent maintenance item on aging roofs.