9: Building the Barrel Vault Ceiling

As part of the "fix up an old house then sell it to a rich person" strategy we started out with I thought that some flash would help with the sales job.  It wasn't all about the money--I wanted to show off a little too.

With that in mind I decided to build a barrel vault ceiling in the north bedroom.  I had seen one constructed while working on a high end house and so had an idea of what to do.

(Click on any image for a larger view.)

In an ordinary building, the ceiling joists would connect the opposing walls at the height of the two soffits.

To be able to vault a ceiling, it's necessary to remove the ceiling joists.  Those joists keep the outward thrust of the load imposed on the exterior walls by the rafters from blowing out the wall framing, so you need to replace the ceiling joists with either a load bearing ridge beam or some kind of trussed rafter.  I chose option number two.

I built modified scissor trusses, as shown in the diagram above.  Beneath the new roof structure I stood up the ribs of the vault.  These I made by first laminating 3 sheets of 1/2" plywood together to create 1" thick by 12 ft long by 4 foot high blanks .  Knowing that a barrel vault is half of an ellipse, I drew it on to each of the 7 rib blanks with 2 nails, a long piece of string, and a pencil, then cut the shapes out. 

The temporary scaffold is partially blocking the view of the curved, elliptical ribs.

After removing the scaffold, insulation followed by a plastic vapor barrier went up.  Then a series of 1x2 straps were screwed across the plywood ribs.  Here my friend Andy is putting up the first of two layers of 1/4" drywall.

Before hanging, wetting the 1/4" drywall and leaning it against the wall gets it started bending.  Once on the ceiling it takes a little finesse to get it to slide into place.

It turned out beautifully.