Gambrel roof

A gambrel or gambrel roof is a usually symmetrical two-sided roof with two slopes on each side. (The usual architectural term in eighteenth-century England and America was "Dutch roof.") The upper slope is positioned at a shallow angle, while the lower slope is steep. This design provides the advantages of a sloped roof while maximizing headroom inside the building's upper level and shortening what would otherwise be a tall roof. The name comes from the Medieval Latin word gamba, meaning horse's hock or leg. The term gambrel is of American origin, the older, European name being a curb (kerb, kirb) roof. Europeans historically did not distinguish between a gambrel roof and a mansard roof but called both types a mansard. In the United States, various shapes of gambrel roofs are sometimes called Dutch gambrel or Dutch Colonial gambrel with bell-cast eaves, Swedish ~, German ~, English ~ , French ~, or New England gambrel.

The cross-section of a gambrel roof is similar to that of a mansard roof, but a gambrel has vertical gable ends instead of being hipped at the four corners of the building. A gambrel roof overhangs the façade, whereas a mansard normally does not.

Gambrel is a Norman English word, sometimes spelled gambol such as in the 1774 Boston carpenters' price book (revised 1800). Other spellings include gamerel, gamrel, gambril, gameral, gambering, cambrel, cambering, chambrel referring to a wooden bar used by butchers to hang the carcasses of slaughtered animals. Butcher's gambrels, later made of metal, resembled the two-sloped appearance of a gambrel roof when in use. Gambrel is also a term for the joint in the upper part of a horse's hind leg, the hock.

In 1858, Oliver Wendell Holmes, Sr. wrote:

Know old Cambridge? Hope you do.—
  Born there? Don't say so! I was, too.
(Born in a house with a gambrel-roof,—
  Standing still, if you must have proof.—
"Gambrel?—Gambrel?"—Let me beg
  You'll look at a horse's hinder leg,—
First great angle above the hoof,—
  That's the gambrel; hence gambrel-roof.)

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