Combining old and new might seem to complicate what is usually a lengthy construction process. But these systems are fast. The foundation comes in precast sections, the timbers with precut joints, and the insulated sheathing panels with pre-finished surfaces that form walls and ceilings between the beams. A small house with these energy-efficient systems goes from gravel on the ground to closed in and weather-tight in three weeks.
Foundation
Precast concrete foundation panels are made in a factory, so there is no rain to dilute the mix and no blistering sun and high wind to dry it out too fast. No forms are needed, which can save days of labor on a house with twists and turns in the layout. Typically, the panels are trucked to the site and set by crane as installers caulk and bolt together corners.
The North Carolina house designed by architect Ken Wertheim has a proprietary system from Superior Walls (superiorwalls.com). The dense panels are very strong (5,000 psi) reinforced concrete and come backed with 2.5-inch foam panels rated R-12.5 and steel studs ready to accept drywall.
Wertheim, based in Asheville, N.C., says, "The walls come pre-insulated, so they provide the homeowners with an energy-efficient basement. And the builders appreciate using them because they install in less than a day." This means a builder — on a new house or addition — can start framing the day after the foundation is installed.
Framing
This is the way houses were built for hundreds of years, with a skeleton of huge beams carved out with hand saws, axes and chisels. But the real art of timber framing is in the interlocking joints — the basic mortise and tenon and others — that tie the frame together and are pinned in place with large wooden dowels. The twist in timber framing today is the precut kit.
Even local builders who do only a few houses a year can use computer-directed machines to cut the components. Some still do it the old-fashioned way, for instance, rescuing old barn beams and scraping them down by hand. The good ones cut each timber to the specs, assemble the frame, make any necessary adjustments, then pack the pieces for shipping. Assembly on site is fast.
The North Carolina house has a precut frame from Timberpeg (timberpeg.com), a New Hampshire-based company in business since 1974. But timber-frame homes are not just for the northeast. Timberpeg has regional sales offices across the country. Timberhomeliving.com lists about 40 companies building in every region.
Sheathing
SIPs (structural insulated panels) have been around for a while, but follow through with the idea of prefab products that bundle several building processes. They are strong enough to span between timbers and often tuck together with tongue and groove edges. The structural sandwich comes with a finished ceiling on one side plus layers of insulation and roof decking on top.