Jack Arches are common in Capitol Hill. They work well with a tall rectangular window with the inside of the window close to the underside of the ceiling on the interior side of the building.
Jack arches are also sometimes referred to as “flat arches” or “straight arches.”
A jack arch is an alternative to a one-piece lintel, and the individual units in the jack arch make it easier to lift and hoist than a heavy solid lintel.
The jack arches shown in the photo below are here in Capitol Hill. This is a bonded arch, with about a 60º skewback. The greater angle creates more stability.
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