Trimming out a large archway

[joe milana]

Suppose you have a large archways (7' high x 8' wide) on either side of a hallway leading into a dining room and a living room and you wanted to trim them with wood. How would you do it?

[Jim Becker]

Bendable ply or kerfed material along the bottom face of the arch and a segmented molding assembly constructed off the wall and then applied. Vertical trim gets done last after the arched area is done to insure everything comes together in the correct places.

This is certainly a lot easier to do if it's a painted trim situation than if you need something natural. With painted, you can also use some non-wood products that are bendable to make the job go easier.

[Ben Davis]

Agree. Bendable plywood and mouldings are a great place to start. With opening that large I would think that pillasters would fit in nicely. Check out the White River( http://www.whiteriver.com) website and look at their design ideas pages. You can also download their complete catalog (.pdf version) and study how things are put together. Gary Katz's website is also of good use as is looking through the Journal of Light Construction; all of which you can accomplish online!

Make a mock up!

[joe milana]

Thanks for the Ideas! The thing about plywood is that what if I wanted a slight "reveal" as on a typical door jamb?
I am imagining a plywood "male" mold that I would bend and laminate 5 1/2 " wide thin sheets of oak over. I could then use that "plug" to support the jamb and attach my casing to it, then lift the entire assembly to place, attach, then add vertical trim.

[Ben Davis]

door or no door?

[joe milana]

no door. Again, the opening is approximately 8'w x 7' h

[Darren Salyer]

Thanks for the Ideas! The thing about plywood is that what if I wanted a slight "reveal" as on a typical door jamb?
I am imagining a plywood "male" mold that I would bend and laminate 5 1/2 " wide thin sheets of oak over. I could then use that "plug" to support the jamb and attach my casing to it, then lift the entire assembly to place, attach, then add vertical trim.

If you bend 5 1/2" wide thin sheets of oak, don't you end up with an edge similar to plywood? I Use bending ply all the time, and if it is stain grade work, veneer on the plywood edges gives the appearance of a solid wood piece.
Darren

[Bill Dunn jr]

If you have not finished it yet here is a picture of one I did a while back. It is cherry and I laminated the arched jamb out of 4 thin pieces of cherry. The beaded casing is easy since you can use a laminate trimmer with a beading bit (and steady hand).