Centex, one of the nation's top production builders, announced this month that the company will be pushing energy-efficient construction in a key coastal market: South Carolina's Low Country. Centex said it will complete models that showcase its newly developed "Energy Advantage" package in April and May in at least three communities: Shadow Moss, near Shell Point in the Hilton Head area; Rice Field at Carolina Bay, in west Charleston; and Brookstone in Barefoot, near North Myrtle Beach (the same community hit this month by a catastrophic wildfire). Centex announced plans this month to merge with Pulte Homes, another leading national builder, to form what will be the biggest homebuilding firm in the national market. In the current economy, that result may amount to less than meets the eye; Luke Johnston, on the Seeking Alpha blog site, takes a close look at the charts and concludes that the company created by the merger will have lower sales in 2009 than either firm had on its own in early 2008 ("Centex - Pulte Combination: When One Plus One Is Less than One," by Luke Johnston). Be that as it may, Centex's escalation of its energy efficiency-based market positioning is still a sign of the times. Big builders have been refining their energy-efficient chops for more than a decade now, with support from the U.S. government, in the Department of Energy's Building America program. Coming out of the current recession — and even during it — they can use this experience as a competitive edge. Sam Rashkin, one of the Environmental Protection Agency's point men in the Energy Star program for builders, has made much in his training and educational programs of the fact that supplying top energy performance puts a new house in a strong competitive position versus any existing house. In 2007, Rashkin noted that if a builder includes the right kind of energy efficiency details, "you just made 90 percent of your competition obsolete. They don't compete with you." (See "Between the Gaps," by Ted Cushman.) Sam Rashkin was talking specifically about framing and insulation details that block "thermal bypasses" — air leaks and insulation voids that degrade the integrity of a building envelope. Details that comply with Energy Star's "Thermal Bypass Checklist," as he observed, are almost impossible to add as a retrofit to an existing home — "not without taking it down to the studs as a gut-rehab.” The details Centex touts in its "Energy Advantage" houses do not include any mention of thermal bypasses. But most big homebuilders have now learned (at least in theory) about how significant those bypasses can be. And the items that Centex does include in its new package are likely enough to set its new homes apart from existing older homes in the same market. Here's the list from a Centex press release: • Energy monitor (a meter to supply real-time information about electricity usage and expense)

• Whirlpool brand ENERGY STAR® qualified appliances

• Lennox high-efficiency HVAC system

• Programmable thermostat(s)

• Low-emissivity windows

• R-38 insulation and radiant-barrier roof decking in the attic

• Compact fluorescent lights in high-traffic areas Centex touts studies indicating that its new "Energy Advantage" houses are 22% better performing than a new house built to the 2006 International Energy Efficiency Code, and as much as 40% better than a typical ten-year-old house. And while most of these items could be added to an existing house, doing so would not be free. So the latest Centex models represent a serious challenge to any other builder in the Charleston-area market. On the other hand, energy-efficient construction methods are not some kind of trade secret — Building America, the Energy-Efficient Builders Association ( www.eeba.org), and many other groups are devoted to spreading the word. So any builder who's willing to make the effort should be able to match, or even top, Centex's results. For information on high-performance houses in a wide range of climates, one good information source is the website of Building Science, Inc., at www.buildingscience.com. The Building Science team has published a set of high-performance design concept examples on this " Designs that Work" page. Any of the examples in the Mixed-Humid or Hot-Humid sets would be instructive for a builder in Low Country South Carolina. Click for larger version

Energy-efficient details for Mixed- and Hot-Humid climates can be found in the "Designs that Work" pages on buildingscience.com