Carl Franklin Homes: Equal Opportunity to Energy Efficient Housing in the Lone Star State

Carl Franklin Homes is teaming up with the Dallas Affordable Housing Coalition and the Dallas Housing Authority to create affordable, energy-efficient, durable homes for low-income homebuyers. The project aims to expand homeownership opportunities in the Kensington Park area of Dallas by producing homes that cost significantly less to operate and maintain in comparison to those which are more conventionally constructed.

Each year, Carl Franklin Homes produces 50 to 100 housing units targeted at the entry-level workforce. Builders experiment with innovative technologies to offer the best range and quality of amenities while maintaining a sales price of between $80,000 and $90,000 per unit - or about half of the median home price in Dallas. Carl Franklin Homes has adopted the Partnership for Advancing Technology in Housing (PATH) initiative goals of improving the quality, durability, energy efficiency, environmental performance, and safety of housing. Originally a PATH Demonstration Site, the National Association of Home Builders Research Center showcased the Kensington Park project during the January 2000 International Builders Show. The exhibit included PATH-evaluated technologies such as Structural Insulated Panels (SIPs) and Geothermal Heating and Cooling units. Geothermal technologies take advantage of the earth's relatively constant temperature below the frostline - about 55 degrees Fahrenheit - to heat and cool homes, using far less energy than conventional systems.

Structural Insulated Panels Aid Durability and Promote Energy Conservation

SIPs offer the advantages of improved thermal, structural, and acoustic enhancements to a home. In the Carl Franklin Homes, the builder's standard practice is to construct the exterior shell using SIPs for walls and roofs. SIPs consist of a core layer of rigid foam sandwiched between two structural skins made of oriented strand board. The high-density bonded foam acts as a bridge to augment structural capacity while providing far greater insulative value in comparison to more conventional materials. Panels are assembled with minimal or no additional framing to form exterior walls and roofs that provide high vertical and horizontal load-bearing capacity and remarkable resistance to thermal bridging.

Conventional wood framing creates a structure where every vertical stud and batt insulation joint represent a minor thermal bridge and possible air leak. Conversely, panel systems offer a solid, continuous air barrier, a complete thermal break, and uniform insulation coverage. Compared to conventional home construction, using SIPs results in a more airtight dwelling with better and more uniform insulation. The house is more comfortable, quieter, and highly energy efficient in both winter and summer. Although SIPs cost a bit more than other construction systems, they require considerably less skilled labor and can be built in far less time. As a result, costs are competitive with conventional 'stick-built' construction. Carl Franklin Homes makes the system cost- effective for low-income housing by training its crews to assemble SIPs, and by using three basic home layouts that share common features and prefabrication elements.

Geothermal Heat Pumps Improve Energy Performance

Carl Franklin Homes also uses Geothermal Heat Pumps to improve energy performance. Geothermal Heat Pumps have tubes or pipes filled with a circulating anti-freeze-like liquid, which are looped into the earth to take advantage of the constant temperatures below frostline. In the winter, the liquid medium circulates through the system's underground loop and attains a more moderate temperature compared to the extremes of heat and cold outside. The indoor mechanical unit then either heats or simply circulates the naturally temperate fluid (depending on the season) and distributes it throughout the building. In the summer, the liquid cools the air inside the building by carrying heat from the building into the earth and returning it at a cooler temperature.

Manufacturers state that geothermal systems operate 30 to 60 percent more efficiently in comparison to conventional fossil fuel systems. Geothermal systems are particularly effective in Dallas, because constant soil temperatures enable the system to operate efficiently, even when there is a significant difference between outside temperatures and desired internal conditions.

For more information on geothermal heating and cooling, visit the Geothermal Heat Pump Consortium's Web site at www.ghpc.org.

Tankless Water Heaters Help Reduce Utility Bills

Traditional tank heaters hold a fixed supply of preheated hot water. Keeping the water supply hot 24 hours a day can account for as much as 14 percent of a typical home's utility bills. New technology warms the water instantly as it flows through a small gas or electric heating element in the supply line. As a result, energy consumption only occurs during the short periods when hot water is actually used.

The Proof Is in Homeowners' Pockets

To document the savings resulting from its energy investments, Carl Franklin Homes collected utility bill information from buyers over an 18-month period. For a 1,240 square foot home with cathedral ceilings, utility bills averaged just $32 per month. By comparison, one homeowner's bills from a former, conventionally built residence averaged over $70 per month.

In the face of escalating urban real estate prices, low-income housing advocacy groups are struggling to maintain affordable housing stock in metro areas. Carl Franklin Homes offers a design solution to the challenge of affordable housing and at the same time contributes to the supply of durable and energy-efficient housing in its community.

For more information, contact: Bruce Starr, (301) 430-6314, bstarr@nahbrc.org