Eave

On a tile roof the eave begins with a piece most definitions skip. The FRSA-TRI Florida High Wind Concrete and Clay Tile Installation Manual defines an eave closure as “A prefabricated EPDM rubber, metal, concrete or clay material or mortar to elevate the first course of tiles and to enclose the cavity formed by the tiles at the eave.”

InterNACHI's tile roof inspection course names the same piece a stop and gives its purpose: “Medium- and high-profile tiles should have a stop installed along the eave beneath the starter course that will help keep birds and insects from entering the space under the tile.” InterNACHI heads that passage Birdstop, the other name the piece goes by.

Profile is what makes the cavity. A flat tile lies close to the roof deck, while a curved tile leaves an opening under its arch at the bottom edge. InterNACHI says medium-profile tiles may be S-shaped and high-profile tiles are typically barrel, and Eagle Roofing Products calls its high barrel tile an S-tile. On a high-profile tile roof, that opening along the eave is what the closure fills.

ARMA's Residential Asphalt Roofing Manual gives the eave one line: “The horizontal, lower edge of a sloped roof.” The FRSA-TRI glossary uses the same words without the comma. Horizontal and lower are the two words that separate an eave from every other edge a roof has.

The rake is the other kind of roof edge. ARMA defines it as “The inclined edge of a sloped roof over a wall” and the FRSA-TRI manual as “The outside edge of a sloped roof at the gable.” A roof with gables has rakes climbing its ends and eaves along its sides. A hip roof, which ARMA describes as sloping on all four sides with no gables, has eaves the whole way around.

The eave is also where roof measurement starts. ARMA defines span as the horizontal distance from eave to eave, and it measures rise from the eaves line up to the ridge.

ARMA defines the overhang as “That portion of the roof structure that extends beyond the exterior walls of a building.” Where a roof overhangs, the eave is the outer edge of that overhang, and two more words name the parts that finish it.

The fascia is the board on the outer face, which the FRSA-TRI glossary describes as covering the rafter or truss ends at the eave. The soffit is the underside, which ARMA calls the finished underside of the eaves. Each has its own entry and neither is defined again here.

Then the gutter. ARMA's glossary calls a gutter “The trough that channels water from the eaves to the downspouts.” Where a house has gutters, they run along the eave line, catching what comes off the edge above.

Water that runs down a sloped roof has to leave it over an edge. ARMA defines a drip edge as a material “used along the eaves and rakes to allow water run-off to drip clear of underlying construction.”

How that metal is shaped, and where it is called for, belong to the drip edge entry.

Gutters along an eave also come up when a roof is washed, since the rinse leaves the roof the same way rain does. That question, and what the documents say about it, is taken up under whether roof cleaning can damage gutters.