For Passive Design in a Humid Climate, Try Concrete

Important decisions during four years of pre-construction design led Gray to building a home that he expects will cost next to nothing to run and maintain. The L-shape of the home, for example, is not the most effective for passive design strategy, but Gray made up the difference by ensuring the house was oriented at the ideal angle and that the addition of shading would minimize heat gain. Solar panels are added to make up for energy loss in design and the decision not to invest in the most highly efficient windows. Gray went for the extra cost of a solar array at about $40,000, knowing that saving a bit of money by going geothermal would not bring energy costs all the way to zero. All of the windows cost around $50,000 and are triple-glazed. Finally, he made the smart decision to add about $4,000 in insulation costs knowing it would save about $200 per month is energy bills, paying for itself in under a year.

Concrete was chosen for home construction because of its durability and ease of insulation. Ideal for a wet climate as it won't encounter bug or mold issues, concrete is far easier to maintain overtime. The walls are made from layers of two inches of concrete, seven of styrofoam, and a final five inch layer of concrete with rebar.

Universal design tactics are used throughout the house meant to be a long-term family home. Rooms are built to accommodate hardwood floors after the kids are grown and the single-story house is entirely wheelchair accessible complete with a ramp. Other efficient strategies include all LED lighting and reused brick for interior walls purchased for $50 at the local dump.

The only thing Gray didn't spring for is the Passive House certification, which would have added $10,000 to a home that cost $840,000 to build. Even without the certification, this house will keep the costs just as low.

Read more about the passive-designed home on Houzz.