Building A Barrel Vault Ceiling 

A barrel vault is an architectural element that is known as far back as ancient Egypt, and was also used in Roman architecture. A barrel vault ceiling is a curved ceiling formed by the extrusion of a single curve. It is basically a series of curved rafters.
The barrel vault pictured is not structural and is built down from existing 2×12 cathedreal ceiling rafters. There are interior partition walls on either side that the barrell vault ceiling rafters. The actual strucural weight of the roof is supported by the 2×12 roof rafters.
We figured out the barrel curve we wanted and made a pattern with a router and a trammel, cutting all of the plywood needed for the barrel vault ceiling.
This scrap material will also act as a nailer for the plaster strapping to be installed after.
The plaster strapping or ribs of this arch [photo above] were made from strips of 3/4″ plywood ripped to 2 inches. The 2″ strapping was spaced every 2″ and secured to the barrel vault rafter with screws.
Finishing the Barrel Vault Ceiling:
The barrel vault ceiling was finished with two layers of thin 1/4″ blue board, seams overlapped. 1/4-in. blueboard will bend and form a
TIP: Draping the blueboard over a couple of sawhorses may help start the curve. A coat of thin set veener plaster finished the barrel vault.
Once finished crown molding was installed along base of the arch and left open on the to to allow us to install and hide rope accent lighting. The rope lighting was installed on a dimmer provides a nice warm glow at night.
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