Architectural Detail

Of the many facets that give a house 'charm' one of the more important is Architectural Detail. Portland and the surrounding areas were largely built in the late 1800's and early 1900's, and the overwhelming majority of period houses in this area fall into the Craftsman style of architecture. Because they were built by hand, often by small groups of very talented and experienced craftsmen, they contain details that act as a testament to the builders skill. Exposed corbels and rafters, exquisite built in cabinetry, often hidden storage, all executed with the finest skill the builder could muster. One would imagine that, in an era of craftsmanship, these details would be talking points, giving credence to the avowed skills of the homebuilder, and building his credibility and reputation as a carpenter.

Our house is not one of those...

This home was built (quite solidly) in 1973, in a later era of expansion and sub-development. Additionally, it has been remodeled more than once, and by persons of, ahem, 'questionable skills.' I try to refrain from screaming expletives about useless hacks... sometimes I fail.

This is all background to the point at hand, which is that we wanted to, in our design, add a few Craftsman style details to the house, to add some charm. Exterior details are a later possibility, but that is down the road a ways. One of the first details we decided to add were arched beams on the interior.

In previous posts, we have touched on the two interior beams that Rachel and I installed. These two beams were necessary to carry the load of the ceiling, although they do not have any true structural or roof load. Accounting for the shape of the room and the placement of the beams, we have used them to demarcate the dining area from the rest of the living space, and adding arches to the finished beams helps to give the room a charm and detail that helps to justify the beams. Where otherwise there would be two visible beams with no major purpose other than support, we now have an architectural detail that defines the dining room and adds grace and charm to our living space.

Arches are not particularly complicated, but they are tricky. If one does not figure all the details out beforehand, one runs the risk of a too abrupt transition to straight, or uneven arches, with different lengths and/or radius between one detail and the next. My method of creating these arches was to build the four units, identical in measurement, on the ground, then fasten them into the corners. I worked out (mathematically) what the radius should be in order to use 24" pieces of flexible corner bead (we'll get to that in a minute) and worked backward from there to establish the shape of the side pieces.

The corner units are made of 2x4s, ripped to the correct width, with a radius cut piece of particle board attached to both sides. OSB and plywood are also usable for the sheeting parts, but particle is what I had on hand. I cut all the pieces to be the same size, and assembled them with screws.

After the corners were built, they were installed on the bottom of the beams, in all four corner (both sides of the post and both wall attachments). The sheetrock was then hung on the beams and walls, excepting the curved portions of the arch. The curves were covered with several layers of High Density 1/8" hardboard. Each layer of hardboard was attached to the curves and beam to hug the plywood arch, with the final layer being installed rough side out, to hold drywall mud.


At this point, the project is ready for corner bead. While it is possible to make preformed metal arches out of standard steel cornerbead, it requires very expensive and specialized tools. I elected to use flexible plastic cornerbead for this application. This product is widely available and looks very similar to regular plastic corner, except for one leg of the corner being cut into small lengths. The corner is then carefully bent into place, and attached at the middle, working your way out to the ends and keeping the curve smooth (this is one of the tricky parts). After this arched corner bead is attached, standard straight corner is applied to the rest of the corners.

Next up, drywall mud. One thing to note regarding inside corners such as this, it is almost impossible to mud these in thin layers. The nature of the cornerbead and inside curve is such that you will wind up putting the full depth on at one time. It can be helpful, in situations like this, to use chemically hardening 'hot' mud, as it is less likely to crack while curing in a very thick layer. After several applications and multiple rounds of sanding, we are ready to paint and finish.
What's that behind the arch, you say? That's what we call a teaser, and it's to get you hooked in. Fear not, more posts will be forthcoming!


After paint and finish, we have a beautiful detail that helps define the space, adds character and charm to the overall building, and architectural detail to the house.