Their Future is Bright Green
If homeownership is the basis of the American Dream, Habitat for Humanity makes that dream a reality for some families in the Upper Keys. At their latest project, at the 87.5 mile marker, community resources, the Baustisto family and local volunteers are building a super energy efficient, eco-friendly home many would covet.
Habitat for Humanity of the Upper Keys has completed 23 homes since it began in 1988. The process to match a home to homeowners includes selection of a site and sponsorship, advertising for families to qualify with income guidelines and assessing their ability to provide the 300 to 500 hours of sweat equity mandated. Consideration is given, in the selection of the family, to the need for housing caused by a substandard condition, such as over-crowding, mold, roof issues or termites.
The two most notable features of this new home, number 24 for the Upper Keys Habitat contractors, are the many energy conservation measures used in the design and construction and the rainwater harvesting system.
The building shell, including roof and floor, are made of Structural Insulated Panels (SIP). The panels are made of an insulating layer of rigid foam sandwiched between two layers of engineered wood sheets. SIPs are a relatively new building material combining structure and insulation in one rigid panel.
Engineering for structure, solar power, energy conservation and water efficiency, including the rainwater catchment system for the house, was provided by Solaria, of Marathon. Steve Grasley, system designer for Solaria, explained, “I remember as a child in social studies class, when the population of the world rolled over to a billion. I learned the U.S. had 5 percent of the population and consumed 25 percent of the resources. I thought: that is insane. You can do more with less. You do that by understanding your world and designing to work with it.”
The panels used in this home were constructed at PorterCorp in Michigan. Once shipped to the Keys, the numbered sections were assembled onsite by local crews and CBT Construction. Being familiar with the process from an earlier project, using SIPs to enclose an existing home in Key Largo, Chris Trentine, owner of CBT Construction, used his experience to keep the process affordable.
Building costs in Monroe County are high, compared to the national average, due to the strict building codes for hurricane-force winds and building higher for flood levels. Steve Grasley explained, “Building up one level for our elevation adds 25 percent to the cost of a home. The average cost in Monroe County for normal construction would be around $250 per square foot. National estimates for a similar home would be $175 per square foot. With the SIPs simplified design, structural benefits, such as an integrated foundation, and minimized energy needs, saving money over larger capacity systems, this home could be built for $120 to $150 per square foot.”
While SIPs construction materials might be slightly higher in cost than common construction block or frame materials, SIPs construction is stronger because of the materials and the engineering, cutting normal structural costs while producing a superior “structural envelope”. Pre-engineered, the shell goes up quickly and that saves labor costs. A smaller air conditioning unit is used, due to insulation efficiency and smart design, and thousands of dollars are saved on both the unit and the electrical circuits needed.
Jack Niedbalski, director of Habitat for Humanity of the Upper Keys, noted, “The 1189 square foot home, even with its 16 foot high ceiling expanse, is requiring only one half-ton air conditioning unit, which is Energy Star rated and zoned to different parts of the house at different times of the day.”
Often the largest source of heat gain for a Keys home, the roof on this home is 10-inches thick, rated at R-42 (resistance to heat flow) and finished with white metal roofing. In comparison, common construction of a roof would average a respectable R-30. But SIP walls are 6-inches thick and provide R-27 insulation compared to the average R-11. The 12-inch thick SIP floor delivers a R-60 factor, far excelling an average R-5 rating.
The three-bedroom two-bath home features more passive energy saving designs. The impact resistant windows are placed to allow cross ventilation in temperate weather. Windows on the hotter south and west sides of the home are smaller, to minimize heat intake, and larger windows maximize the prevailing breeze on the east side of the house. The lot provides shade trees on the west exposure and a generous overhang around the house keeps the summer sun from striking the windows, minimizing heat gain.
Smart design choices make this a “near zero-energy” home, adding little, if any, cost to the construction, resulting in effortless and constant savings. A gas oven/range and clothes dryer will cut electric consumption. A 100-gallon solar water heater will provide for the family of four. The estimated monthly cost for electric for a similarly sized house would be $250. The new Habitat home will cut that by 80% for an average cost of less than $60 a month.
The home will be engineered and rigged for future solar panels, which could produce enough electricity to offset the energy used to run the house.
The other unique feature of the home, a 10,000-gallon rainwater cistern, will be the only water source for the family of four. Their projected use is 3,000 gallons per month. The roof collection includes a “first flush” system that allows the first minutes of a rain to wash the roof and run water away from the cistern line, then it automatically switches to collecting the clean water in the tank. Moving from the cistern tank into the house, a triple-filter system provides water to the house and a high-performance nano-filter supplies potable water in the drinking lines.
To make the most of what water is collected, low-volume, Vacuflush toilets use a vacuum system and very little water to flush. A front-loading, water saving clothes washer will get plenty of use with a family of four, using half the water of a top load machine. The native landscaping uses xeriscape principles to minimize the need for water. Aerated shower heads and faucets maximize water economy.
With no current sewer system to tie into, the contractor pre-trenched for sewer lines in the cap rock, saving expenses and inconvenience down the road. Until then, the septic tank is 2010 standard compliant. If it is determined that the rainwater cistern system is not meeting the family’s needs, a water meter and lines to the house can be installed using the same trenches.
Miguel and Lisset Baustista and their two teens, Andy and Amanda, are putting in more than their required sweat equity of 500 hours, with teens working along side their parents. They are justifiably proud of their new home and hope that early November will see them settled in.
The Upper Keys community has supported the project fully. The lot, between US-1 and the Old Highway in Islamorada, was donated by The Village of Islands along with funding budgeted to address affordable housing. Forest Tec is the official sponsor donating funds offset by a tax credit program and supplying materials at a deep discount.
Florida Keys Electric Coop donated the use of a crane to help the crew of five set the SIP panels in place. Danny’s Tree service cleared the site. Houston Air, Keys Tropical Windows and Lindholm Roofing offered services and materials at cost.
If you are interested in learning more about the Habitat for Humanity process, donating supplies or becoming a sponsor, stop by the store at 98970 Overseas Hwy. in Key Largo or call 453-0050. An application and qualifying requirements can be found at www.habitatupperkeys.org.