Tucked amidst towering maple trees on a sprawling southern Missouri farm, lies a tidy farmhouse with a white-columned porch. At first glance, it seems typical of a 19th-century Midwestern homestead, but this country manor holds a surprising secret. Though the original three-story structure was built 100 years ago, a spacious timber frame addition was completed in April 1998.

“We needed a place to entertain, and we always wanted to add a family room,” explains the home owner, who bought the home with his wife in 1983. “We also have a log home in Montana, and we liked the idea of a log addition, but it wouldn’t have been appropriate for our farmhouse,” he says. A timber frame addition with its exposed wooden beams, open rooms and soaring ceilings, seemed like a nice compromise to the home owners.<

Today, the transition between the addition and the original 2,700-square-foot farmhouse appears virtually seamless. But as the couple discovered, creating a subtle union between the old and new interiors would require ingenuity, creativity and the collaboration of a skilled group of professionals.

The first step was contacting Hearthstone Inc., a Tennessee-based timber frame producer, in the spring of 1997. Hearthstone then referred the couple to Jan Donelson, a Hearthstone distributor and an architect in St. Louis, who had designed another timber frame addition in the area.

In August 1997, the general contractor, Paul Amsden of Farmington, Missouri's Amsden Construction, broke ground on the project. Shortly afterward, an erection crew, subcontracted by Hearthstone, assembled the timber frame, which included a great room, new master bedroom and an expanded kitchen.

Foam-core panels were used to enclose the post-and-beam frame, which is connected by traditional mortise-and-tenon joinery and 1-inch pegs. Both the pegs and the frame itself are oak, known for its beauty as well as its density.

"Once it cures out, it's just as hard as iron," Jan says, who says Hearthstone typically employs independent graders to select the highest grade oak.

Joining this new addition to the old farmhouse and making the exterior appear cohesive was relatively simple. "Basically, a timber frame is independent; it will stand by itself," Jan says.

After stripping off the siding and shingles from the original structure, "all you have to do is close off the gap. You insulate the joint, which may be from a half inch to two inches apart. Then you just trim it back out." In this case, a unified facade was achieved by applying redwood beveled siding to match the original.

Creating a comfortable flow on the interior was a greater challenge. The nucleus of the new timber frame structure is the great room, which features a 26-foot-high cathedral ceiling supported by a hammerbeam truss. "It gives a beautiful framework, like a picture frame, around the great room," Jan says.

The family loved the new addition, but felt something was missing. "We wanted to tie the timber frame theme into the rest of the house, so it looked like it was built all at one time," says the home owner, who consulted interior designer Nancy Bridwell of Bridwell Interior Design Inc. in Festus, Missouri.

After a series of brainstorming sessions, the pair decided to add structural oak timbers to the sloping ceiling of the newly-expanded kitchen, which had been widened by eight feet to accommodate a breakfast area.

Next, they turned their attention to a hallway that had been created by knocking out walls between several adjoining rooms, in order to connect the timber frame portion of the home with the old section.

Nancy suggested adding a tongue-and-groove ceiling and cosmetic timbers to spruce up the passageway, which also serves as the primary entry to the home. To further emphasize this rustic theme, whimsical elk chandeliers were evenly spaced throughout the hallway.

The floor of the corridor was covered in sturdy tiles, maintaining an allegiance to natural materials while providing a subtle contrast with the white oak floors used elsewhere in the home. "As beautiful as the wood is, you can almost go to excess," Nancy says. "You have to assess when you're bordering on monotony."

Of course, a certain amount of cohesion is necessary to create a sense of unity. In addition to carrying the tongue-and-groove ceilings and oak timbers into other parts of the house, Nancy also found a basketweave-style wallpaper, which she applied to the downstairs hallways, going up both staircases, and in the old farmhouse on the second-floor hall. "The wallpaper really tied it all together," she says.

The key to building a successful addition is consulting an interior designer or architect early in the process. "I've had people call us after they've built a room and say, 'This just doesn't work right.' If they would have called me before they started building, I could have fine-tuned a few things," Nancy says.

Two common mistakes are not incorporating enough architectural detail and not planning how to properly light a timber-framed room, which can be dark and cavernous if not properly illuminated. "Those things shouldn't be an afterthought," she says.

Jan also warns that "additions usually end up costing more than new construction, because you need to retrofit a lot of things, plus budget for some surprises you don't know about." Typically, Jan says, an addition can cost 10 to 20 percent more than building new.

The timber frame package for this addition in southern Missouri cost about $85,000, but the home owner confesses that he has no idea what the price tag was on the total renovation, which included redecorating the original house and adding a new foundation. "I didn't want to keep track," he admits, though he says the timber frame portion was "nothing compared to the overall cost."

But the final result was well worth the time and expense. "It's fantastic," the home owner says. "It's added a whole new look to the house."