By Katherine Salant
| From an Idea to a Timber Frame House To build a timber frame house, you need to engage both a timber frame firm and a general contractor (GC). The timber framer will supply both the timber frames and the structural insulated panels (SIPS) to enclose the timber frames and the rest of the house. The GC will prepare the site, build the foundations, and oversee all other aspects of the job. However, some timber frame firms build the entire house, and some supply only the timber frames. To come up with a plan, you can work with an architect or go directly to a timber framer. Most will help you design your house and produce drawings with sufficient detail to get a building permit and hire a GC. Some timber framers will also help you find a GC who is familiar with timber frame construction. Before you spend much time planning a timber frame house, though, make sure you can afford it. Golden, Colo., architect Judd Dickey, who specializes in timber frame design, said when he meets with prospective clients, the first thing he discusses is the cost. "A timber frame house is expensive. That's the big gorilla on the block." Compared to a conventionally-framed custom-built house (all the walls, including the exterior ones are built with wood studs), Dickey, whose practice is nationwide, said that a hybrid house with a timber frame great room encased with the structural insulated panels (SIPS) and SIPS panels for the rest of the exterior costs about 20 to 25 percent more. Three timber framers who build all over the country said in their experience, a hybrid timber frame house, on average, adds about 10 to 20 percent more to the cost of the project. Shelburne, Vt., architect Steve Moore, who also specializes in timber frame designs, urges his clients to see a lot of timber frame houses before they get locked into a plan, especially if they want a two story great room. "In the magazines," he said, "they always show the huge spaces because the big volumes photograph more spectacularly. But sometimes they are not so intimate." Though you might imagine a timber frame as more suited to an isolated spot overlooking the rugged Maine coast or hugging a mountainside in Colorado, Moore said you can build them just about anywhere. He's currently designing one that’s 20 feet form a neighboring house and overlooking a golf course in Louisiana. |
Once inside the Baker's house, you take an aesthetic leap even further back in time. The two-story great room with its sloped paneled roof and elaborate system of trusses, posts and beams has the makings of a medieval monastic dining hall, though the adjacent island kitchen is definitely 21st century.
In both cases, the elaborate framing system, which is held together by complex wood joinery and wooden pegs, are timbers frames, a building tradition that is more than 2,000 years old and found with much regional variation throughout Europe and much of Asia. Timber framed houses were also common in North America from the time of the first European settlement until about 1850.
The distinguishing characteristic of the old American timber framed houses, compared to those of other regions, is the exterior - the timber frames are covered up. This beefing up of the exterior was made soon after the first European settlers arrived and discovered that the harsher climate of the New World required a wall that was more waterproof. The walls that worked well back home - woven reeds packed with mud and placed between the timbers of the frame - leaked like crazy. In New England, the settlers covered the timber frame with clapboard siding. In the south, settlers encased the timber frame in brick.
Until about 1850, most houses in the U.S. were built using some variation of the New England or Southern style of timber framing. But as sawmills began to produce smaller sawn timbers and machine-made nails became widely available, a house could be built much faster for less money. The wood-studded wall construction, still used by most home builders today, soon eclipsed the timber frame, and the craft of timber framing was all but forgotten.
On the East Coast, many 200- and 300-year-old timber frame houses are still standing, but in the rest of the country, which was largely settled after 1850, old timber frame houses, including the ones the Greene brothers designed in California in the early 1900s, are very unusual.
The craft of timber frame construction did not disappear entirely, however. A few fathers still passed it on to their sons, and it was used to build large structures, such as factories, barns and warehouses, into the twentieth century.
Fast forwarding to the 1970s, several individuals around the country, including Frank Baker himself and Tedd Benson in New Hampshire, began working with the few craftsmen who still knew the trade, studying the old timber frame houses and barns that were still standing, and building timber frame houses. As others became interested, this timber frame revival slowly spread across the country. Today there are about 450 timber frame companies. The largest ones, including Baker’s Riverbend and Benson’s Bensonwood Homes, build as many as 50 to 150 houses a year, but many smaller firms build only one or two. The total runs to about 2,000 houses a year, still a very tiny portion of the home building industry.
The 21st century iteration of the timber frame has proved a good fit for twenty-first century houses, as more and more owners eschew formal living and dining rooms for a single great room containing living, dining and kitchen areas. The timber frame is especially well suited for a two-story great room because the trusses, beams and posts add scale and proportion to the space while the bents (the truss and its supporting posts) delineate different functional areas.
The environmentally conscious observer might view timber frames with some alarm, as the large timbers, which can be nearly a foot square, would appear to be from irreplaceable old growth forests. Timber framers are an environmentally conscientious lot, however, and many of these large timbers are made from standing dead trees, "buckskins" - dead wood on the forest floor - or salvaged timbers taken from old factories and barns. When new wood is used, it is nearly always second growth, though occasionally timber framers use old-growth wood that was cut in a very controlled fashion.
What would a 17th century house joiner who came over on the Mayflower make of today’s timber frames houses? For starters, he would find a level of quality in the joinery that was rarely achieved in his day and a method of fabrication that was completely incomprehensible. The largest timber frame companies, including Baker's and Benson's, now practice this ancient craft with the most up to date technologies. Computers are used not only to calculate the loads and size the timbers. They are also used to make all the cuts as well. Smaller companies use powered hand held tools and some use hand tools with no power at all. Even when machines are used for the major cuts, however, much of the finish work is still done the old way with a hammer and chisel.
Our 17th century visitor would also be amazed at how fast a timber frame can be made and installed. With machines to fashion the timbers and cranes to install them, the four bents, beams, and ridge beam in Frank Baker’s great room could be cut in one day and assembled and installed at the building site in one day. In the 17th century, it would have taken him months of taxing labor to hew the timbers and make all the cuts for the joinery for a room of this size, and the timbers would have been assembled and erected by a team of men only with great physical effort.
When our visitor took a close look at the joinery and how all the pieces of the timber frame fit together, though, he would see that the essentials of timber framing haven't changed at all.
Our visitor would also experience a level of comfort undreamed of in his day, and he would be surprised at what was enclosing the timbers. In Frank Baker's house and most timber framed houses today, the timber frame is enclosed with structural insulated panels (SIPS), which are made of rigid urethane or expanded polystyrene insulation sandwiched between two sheets of oriented stand board. The SIPS panels create such an air tight envelope that homeowners must install an air to air exchanger to maintain good indoor air quality, and SIPS are so energy efficient, most owners enjoy a dramatic fall in their heating and cooling bills, even when their new timber frame house is bigger than their old one.
An entire house can be constructed with timber frames, but more often, to keep the costs down, only the main living areas are timber framed and enclosed with the SIPS panels. SIPS panels alone are used for the rest of the outside walls, and conventional wood stud construction is used for the interior partitions. Some smaller timber frame companies enclose the timber frame with less costly, but less energy efficient conventional wood stud walls.
If the timber frame begins to sound appealing, you’ll be in good company. Norm Abram, master carpenter of PBS's "This Old House" and host of PBS's "The New Yankee Workshop," used timber frames in the great room of his colonial-styled house. He chose the timber frames because, he said, "it's a beautiful look" that's universally appealing - "When first time visitors walk in they are amazed, and they immediately want to know what it is." Abram's great room, which includes a kitchen, dining and living areas, is large - it's 22 feet wide and 36 feet long. To give the space a warm and cozy feeling, his timber frame is only one story (the peak of his timber frame is only 16 feet off the floor compared to Baker's 25 feet), and he spaced his trusses so that you can see them easily from any place in the room without having to crane your neck and look straight up.
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