Cashiers NC Architects create timber frame designs for hybrid post and beam homes
Sounds impossible. How can home architects create timber frame designs for houses that are also post and beam? Aren’t these two different systems? How can they be merged into a single project? Well, that’s exactly what Cashiers, NC architect Rand Soellner does every day. He blends post and beam systems with timber frame designs.
How does he do this? Rand Soellner Architect is one of the leading timber frame architects in the country. His timber frame designs are featured in books and magazines throughout the USA and the world. Before we get into the how of Soellner’s hybrid approach, let’s examine the Why: cost savings.
Timber Frame Designs and Costs
Soellner has learned that there is a significant added cost associated with pure timber frame designs. There is nothing that he is doing to make this happen. This is what the timber frame industry does to support the cost of what they do. All Soellner is doing is reporting here what he has discovered.
He has seen figures from some of his projects indicate that this cost can be $61.50/gsf (gross square foot), 2008 $, when including SIP (Structural Insulated Panels). Other general contractors with whom Soellner is familiar have reported to him their added costs of $120,000 to $180,000 for just the timber frame portions of perhaps a 3,500 hsf (heated square foot) home in the Highlands, NC area. That’s up to about $51/hsf. This assumes that there are additional square feet included with porches and garages and the like, so if one removes the SIP cost from Soellner’s observation of the bidding on one of his recent projects, that probably is is a similar cost zone.
One of these contractors has his own internal timber frame shop with his own crew, so he is in direct control of his own costs. These costs reported herein for timber frame designs are subject to change and are only a historical reported of what Soellner’s experiences are and should not be used for any sort of financial planning without obtaining the input of your architect and your contractor, working together in your best interests. When Soellner’s clients come to him seeking his services as their home architects to create timber frame designs, he typically asks them a question: “Do you really want a real, honest-to-goodness timber frame house, or do you just want the look?” Not all, but many opt for just the look. The message is: you can get the timber frame design look for pennies on the dollar. Soellner enjoys designing projects either way, based on the client’s preference. And locations where this applies are all over the country, including Cashiers, Waynesville, Highlands, Sylva, Franklin, Mount Mitchell, Asheville, Atlanta and other regions like Denver, Washington and the countryside west of Chicago.
Hybrid approaches to timber frame designs and post and beam architecture
This brings us to the How of Rand Soellner’s hybrid approach to timber frame designs. He enjoys creating 100% authentic timber frame homes as well. As this is primarily an economic choice, Soellner allows his clients to make this selection for themselves. Once they have made the choice, he proceeds in the direction they have selected. For those wanting the economic benefits of the hybrid approach, Soellner believes that he can achieve a near timber frame appearance for a significantly lower financical investment in the client’s house.
Soellner’s hybrid timber frame designs utilize a combination of post and beam architectural design and timber frame technology. He is actually one of the leading post and beam architects as well. Soellner smiles a little when talking about timber frame “techonology,” as he mentions that “Technology” is usually something people mention when talking about computers and other cutting-edge systems. Soellner points out that shipwrights of centuries-old ocean-going sailing ships were responsible for some of the details we see today in timber frame designs of houses and other buildings.
Soellner is referring specifically to the diagonal bracing, usually at a 45 degree angle, that are installed between the vertical post and horiztonal beam in either a sailing ship belowdecks, or in a European timber structure. Soellner says that it is this diagonal brace “technology” that give timber frame designs their strength, even in seismic zones, just like when a tall, old sailing ship heaves up and down and side to side on the oceans. Soellner points out that post and beam systems usually only are comprised of a vertical post (or column), upon which sits a beam, which is horizontal. Although Soellner indicates that there can be steel strapping and nails, screws or bolts securing the beam to the post, the main job is being accomplished by gravity and this is subject to movement, caused by wind or seismic disturbances.
Soellner says that timber frame designs using the diagonal brace are far stronger than just a post and beam arrangement. Most timber frame companies use a German machine called a Hundegger to cut the ends of the braces thinner. This thin blade of wood is called a tenon. Into the posts and beams, they cut a matching bore hole, which is called a mortise. Hence the terms “mortise and tenon” used to described some of the joinery involved with timber frame designs. Usually true timber frame companies will then bore additional small round holes through the engaged brace and posts and beams. In the field, they will pound oak pegs into these holes. Some timber frame contractors have told Soellner that an oak peg can be up to 75% of the strength of a steel bolt of similar size. While that seems hard to believe, this results in a very durable joint that can resist just about anything Mother Nature can throw at it for centuries.
Differences in timber frame designs and post and beam designs.
So what does this post and beam architect do in his hybrid approach that is different from this? For one, he often uses concealed steel screws instead of mortise and tenon joinery, which is one of the most expensive aspects of timber frame fabrication and assembly. The details of how Soellner accomplishes this are a trade secret. Come visit Rand Soellner and if you are a prospective client, he’ll show you how this is done in his timber frame designs. With his hybrid approach takes only minutes per brace and no special machinery. Once again, Soellner loves creating authentic timber frame designs and relishes the opportunity to create timber frame designs for you. The sole reason for a hybrid approach is to give you, the client, the option to achieve a similar appearance for a lot less money.